What is centre of effort? [Archive] - Sawmill Creek Woodworking Community

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Kees Heiden

12-05-2013, 1:41 PM

Derek, what is the centre of effort and what does it to our woodworking planes?

I studied the article on your website but it didn't make me any wiser. I also read some articles about sailing yachts but I fail to see how their centre of effort has correlates with woodworking planes.

Sean Hughto

12-05-2013, 2:18 PM

Chris Griggs

12-05-2013, 2:24 PM

Well, I don't know what a center of effort is but they have a much much lower center of gravity which transliterates into feeling like you need to apply less downward force then you would a bevel down plane. Basically with a BD you feel like your pushing down and forward more where as with a BU you feel like you mostly need to push forward (of course still down but to a lesser extent).

The COG also translates to a very different feel when jointing an edge. On one hand the higher COG of a BD plane makes it easier to sense plumb since you feel the tilt more when you are out of plumb...the flip side of the coin is that once you develop a feel for plumb on a BU plane its a little easier to hold it there as the low COG gives it virtually no tippyness. If your used to one type and not the other the difference in feel can be somewhat unnerving.

Think of the difference in feel between a saw with a very deep plate and an high hang vs one with a shallow plate and low hang. Same feeling.

Kees Heiden

12-05-2013, 2:31 PM

Sean, why do I have a vague, unnerving feeling that you are pulling my leg?

;)

Mel Fulks

12-05-2013, 2:33 PM

No,Kees. That's the same answer Spock gave Kirk.

Kees Heiden

12-05-2013, 2:42 PM

Chris, you are writing about centre of gravity, not centre of effort. The only idea I can think up about centre of effort is the effects from your hands pushing the handles.

Centre of gravity plays a role when the plane changes speed. For example on deceleration (for example when you hit a knot) a high level of gravity wil tend to tilt the plane forward, rolling over the edge which acts as a fulcrum at that moment. That tilt is counteracted with your rear hand pushing down. That could explain your feeling how the BU plane needs less downwards pressure and a BD more. When the speed is constant, it makes no difference. But acceleration and deceleration play an important role in handplaning.

At the other hand, I often have a "surfy" feeling with my wooden coffin smoother. A feeling I don't have with any other plane. It is as if the plane surfs on the wood and only needs to be pushed. Combine that with the effortless glide of a wooden plane and it explains my love for this plane.

Kees Heiden

12-05-2013, 2:44 PM

No,Kees. That's the same answer Spock gave Kirk.

Aha. I'm not much into starwars, as you might have guessed.

But it was funny nonetheless.

Chris Griggs

12-05-2013, 2:53 PM

Yes. I was writing about center of gravity. I don't know for sure what Derek means by COE, but COG to me is really the biggest difference.

From what I gather reading about center of effort it simply refers to the most efficient place to apply force.

The point at which application of the full propelling force would produce an effect identical with that produced by its distribution over the whole...paraphrased from the sailing definition that I'm sure you were referring to in your original post.

I guess one could make the case that because force applied higher up on an object translates to less efficiency in terms of forward momentum... (right? been a while since I took physics, but I just moved to a new shop and I can tell you it was a heck of a lot easier to position my workbench where I wanted it pushing low than high) ...then a plane where the ideal point to apply force is lower would be easier to push (assuming in both cases you were pushing on the center of effort). As in the same amount of force applied lower translates into more forward momentum. So all other things equal a BU plane would require less effort to push forward than a BD plane.

The more I think about it the more I'm pretty sure that's what he is talking about. My experience with BU planes would agree with this concept.

Judson Green

12-05-2013, 3:23 PM

My brain hurts

David Weaver

12-05-2013, 3:25 PM

Aha. I'm not much into starwars, as you might have guessed.

But it was funny nonetheless.

Fortunately, then, the star trek jokes didn't originate from star wars, or you may not have gotten them.

Chris Griggs

12-05-2013, 3:32 PM

My brain hurts

Mine too. I think in reading my own post I'm going to give myself and aneurism.

Kees Heiden

12-05-2013, 3:41 PM

Ah yes Chris, but a BD plane has the handle in the same position as a BU plane (as long as we speak about metal planes). So the COE would be similar, wouldn't it?

(Sorry about the star wars/trek confusion. I'm really not well versed in any of them).

Kees Heiden

12-05-2013, 3:46 PM

When you push high, you are tilting again. The resistance of your workbench on the floor works like a fulcrum. So pushing high wastes energy in the tilting effort.

A wooden jointer has a high handle. But a jointer is very long, so the tilting effect isn't so strong. But maybe that's why the Germans put the handle on the butt of their jointers? Makes for a very awkward feeling plane though, so there is more to it.

Judson Green

12-05-2013, 3:50 PM

Besides, every time I learn something new, it pushes some old stuff out of my brain.

H J Simpson

Chris Griggs

12-05-2013, 3:50 PM

Ah yes Chris, but a BD plane has the handle in the same position as a BU plane (as long as we speak about metal planes). So the COE would be similar, wouldn't it?

I agree. It would. Maybe that's not really whats going on...but in practice there is a feeling of more forward momentum. It might just be the impact of the lower COG allows you to focus more of your force forward and that translates to a subjective feeling of greater forward momentum...it might be the upright tote that are specific to the LV planes...not sure. The phrase COE might not be accurate, but in reading back through his old reviews, I believe what Derek means when he uses the phrase "centre of effort" it is the feeling of greater efficiency in terms of forward momentum from the force you apply.

I don't know what is going on objectively, but I do know that the subjective experience (which is I care most about) is very different, and that I do subjectively experience that feeling of greater forward momentum when I use a BU plane. Whether or not I like, dislike, or care either way about that difference varies from day to day, but I do experience it.

Kees Heiden

12-05-2013, 4:07 PM

Chris Griggs

12-05-2013, 4:18 PM

That's why I like wooden plane so much, they just feel awesome.

Yeah, I know what you mean by the surfing feeling. I only have a couple wooden planes...specifically a couple transitionals, but when they are the right tool for the job they sure are nice to use. Just feels like they're skimming the wood.

Jim Matthews

12-05-2013, 6:20 PM

Pyrrhic Height - the elevation at which one achieves diminishing returns.

Also known as the "maybe a little tighter" moment before the bolt shears off
in the freshly filled oil pan.

Derek Cohen

12-06-2013, 8:13 AM

I think I like Sean's answer the best :)

I will try and expand on this concept - Centre of Effort - which is one I consider to be extremely important if we desire to extract the maximum performance from our tools, not just planes.

Centre of Effort is not the same as Centre of Gravity, although they can have the same effect.

As Kees noted (probably from an article on my website: http://www.inthewoodshop.com/Commentary/ToolingForFeel.html), C of E is a term used in yachting. It refers to the position of power in a sail.

Bear with me as I sidetrack a little, just to provide some context. I am not an engineer. I am a shrink. I understand statistics, reality vs the imagined, interactions between parts, and systems theory. But do not ask me to calculate vectors and forces. I know they are there. I can determine them subjectively, but I lack the knowledge to do so objectively. I am also certain that I am re-inventing the wheel here somewhat, but have not found reading material in this area (that is not to say that it does not exist). My focus has been, like the scientist, to understand how and why tools work and, like the designer, to integrate this knowledge into a tool. Others more knowledgeable can comment on the scientific areas. For the rest of us I think of this as a voyage of discover, and we are all shipmates. The concept C of E is part of the language I use to convey my understanding of the process to you. Can you come up with a better one?

So where does C of E come from and what does it reflect? C of E is a yachting term that refers to the action of the wind on the sail, where it places it force ... low or high on the sail. Pressure at the top of the sail is different to pressure at the bottom of the sail. One does not just rig a sail and off you go - especially windsurfing sails, which is where my experience comes from - it is necessary to tune a sail for optimal performance .... in a way similar to a handplane.

Now this is not intended to be a lesson in sail rigging, so to cut to the chase, forces high on a sail cause instability and forces low on a sail increase power and stability. There are many variations for setting the force area on a sail, such as deepening its curvature to increase power (similar to increasing the camber of a blade to take a deeper cut). However this raises the C of E, and with this goes some control as wind strength increases (analogous to reducing control over grain tearout by increasing the depth of cut).

An important feature of low C of E is increased feedback. In my other article I used the example of a router plane I built - that the design focused on dropping the hands down the plane body and pushing (with thumbs) on the body directly behind the blade head ...

http://i13.photobucket.com/albums/a262/Derek50/Planes/WoodCentral%20Auction/4_zpscb85ebb6.jpg

The Veritas (and LN and Stanley) use handles that lift the forces higher. The feel is completely different.

http://www.inthewoodshop.com/Commentary/ToolingForFeel_html_m2387e87.jpg

One might ask, "well, is the low force just an example of Centre of Gravity?". My answer is no - the difference is that C of G is a force that is permanently low, while C of E is a force that can be directed (i.e. manipulated) to be low. One may build a low C of G into a plane, but it is also possible to lessen this in the tuning. Similarly, there are ways to reduce the C of E in a plane that has a high C of E.

Take, for example, the Veritas LA Jack (below). This was designed with a more vertical handle than the Bailey pattern Stanley/LN bench plane equivalent (say, a Stanley #62, below). What this Veritas handle does is encourage one to push the plane forward. The Bailey, with its forward leaning handle, encourage one to push forward and downward. Pushing downward increases the pressure over the nose (= more resistance). The higher angle of the frog lifts the centre of gravity upward. The higher the frog angle the greater the resistance. In the LA plane the bed is closer to the horizontal, the push is forwards only, and the combination is one of low C of G and low C of E.

http://www.inthewoodshop.com/ToolReviews/Son%20of%20Stan%20or%20LV%20and%20its%20developmen t%20of%20the%20Bevel%20Up%20Jack%20plane._html_3a7 daf5d.gif

The razee style plane attempts to lower the C of E by encouraging that the plane is pushed from lower on the body.

http://i13.photobucket.com/albums/a262/Derek50/Planes/My%20planes/CoopersJointer_html_781967ee.jpg

The plane retains a high C of G as a result of the 50 degree bed. However the lowered C of E places the power lower down and increases its control.

BU planes optimise the combination of low C of G and low C of E.

I think that the original choice of handles for the Veritas BU handplanes was inspired. The vertical handles came in for much criticism from the public. Partly because they looked ugly (in comparison to the beautiful and familiar lines of the Bailey), and partly because the grip was thick and wide. The thinner Bailey handles encouraged one to grip them firmly (since the handles also want to be pushed down). However when you do this with the Veritas they just feel too large. What you want to try is simply pushing them forward with the heel of the hand.

The height of a bench is a game changer. A low bench suits a plane with a forward leaning handle. The forward leaning handle also suits the plane with a high C of G as control and power comes from forcing it down towards the bench. A vertical handle is uncomfortable on a low bench as it causes the wrist to cock too much. So one has to (as I did) swap out the vertical handle for a Bailey type.

http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/NewHandles1.jpg

Unfortunately, this alters the C of E. Get some, lose some. The difference is notciceable.

OK, I could write a lot more. Enough for now. I am interested in your comments.

Regards from Perth

Derek

Derek Cohen

12-06-2013, 8:22 AM

I know what you mean with the feel being very important. That's why I like wooden plane so much, they just feel awesome. But on other days i want the precision of a metal plane.

I can't compare with BU planes, because I don't have any :D.

Hi Kees

The floating sensation of a wooden plane is due to the lower friction compared to a metal plane.

What you need to do is take two wooden planes, both with the same bed angle, one where you push from high up (a coffin smoother) and the other where you push from lower down (a Krenov smoother), and compare which is easier to push and has more control.

http://www.inthewoodshop.com/ShopMadeTools/Planesforthe2013PerthLNToolEvent_html_6425be00.jpg

http://www.inthewoodshop.com/ShopMadeTools/Planesforthe2013PerthLNToolEvent_html_3aef626c.jpg

After this, compare with a Stanley or another plane with a higher handle.

I did this by adding a handle to an HNT Gordon Trying Plane. This is a low plane with a low C of G. By adding the handle and pushing from high up, the whole C of E changed. It is awful - - this weekend I plan to remove the handle ..

http://i13.photobucket.com/albums/a262/Derek50/Planes/Trying%20Plane%20Refit/A9_zpsa306250c.jpg

Krenov was adamant which was the better design (not just the easier to build).

Regards from Perth

Derek

David Weaver

12-06-2013, 9:15 AM

Krenov was adamant which was the better design (not just the easier to build).

Regards from Perth

Derek

It's strange that (and I'm not accusing you of this Derek, based only on a single comment, but of the amateur woodworking world where krenov's word is often regarded as written in stone) more emphasis would be given to the opinions of one accomplished hand tool woodworker than to generations of professionals who made a living solely by production and not teaching, many of those every bit the equal or superior to krenov in ability (unless there was something krenov was hiding).

A krenov style of plane could've been made easily, even if it would've been cutting a mortise out of a solid block, but at a time when makers and users were the most particular and had the most options (and could have made anything), the coffin smoother design was favored instead.

My take on the low center is that it is more like playing football in cast iron flip flops. The plane is less easily manipulated, which might be favorable if someone has trouble directing their plane, but the higher center provides a more agile feel for a user who intends to direct the plane.

Derek Cohen

12-06-2013, 9:20 AM

My take on the low center is that it is more like playing football in cast iron flip flops. The plane is less easily manipulated, which might be favorable if someone has trouble directing their plane, but the higher center provides a more agile feel for a user who intends to direct the plane.

That is interesting David. My experience is the complete opposite.

With regards the Krenov thing, keep in mind I was referring to design and feel. Further, he made the point that a handle (such as a Bailey) restricted the freedom of a hand to move into different positions on the plane body, and that this affected the way the play was used.

Regards from Perth

Derek

Chris Griggs

12-06-2013, 9:27 AM

The COE and COG thing is interesting in how it impacts performance. I've been doing a lot of switching back and forth between my LV LA jack and my MF 15 as I've been prepping leg stock this week. I've really been enjoying using the LA jack for general benchwork much more than I have in the past, but I have been noticing different situations where I prefer one over the other based solely on the COE and COG.

For instance. I had been using my LA Jack almost exclusively, but last night I encountered a piece of stock that had twisted and cupped more than the others after I cut it. I was working the covex side and was having trouble getting the hump out from down the center. I switched to my MF 15 and had a the piece flat in no time. What I realized after was that with the 15, I was better able to feel where the hump was and also control the plane so that I was just removing material from the high center area. Upon reflection what I realized was that when the stock was closer to flat or more uniformly convex the LA jack was easier to use as it so easily plows through the wood and leave a uniformly flat surface. Where things were wonkier and where specific area's needed to be precisely targeted to bring a piece into flat I found the high COE and high COG of the standard bailey style of my MF 15 to be easier to use. This is not to say that either was unsuitable for any situation I was encounter...both are lovely planes and both are all around favorites...but it so happens that what I was working on last night really made apparent how differences in COE and COG made one plane easier to use than the other in specific situations.

Bob Glenn

12-06-2013, 9:44 AM

Okay, I give............in way over my head.

David Weaver

12-06-2013, 9:58 AM

That is interesting David. My experience is the complete opposite.

With regards the Krenov thing, keep in mind I was referring to design and feel. Further, he made the point that a handle (such as a Bailey) restricted the freedom of a hand to move into different positions on the plane body, and that this affected the way the play was used.

Regards from Perth

Derek

That sort of goes back to the discussion of how the plane is being used, I suppose. I haven't ever really found the handle on a bailey plane to be restricting, except the design in general (Since the iron is so far forward) doesn't lend itself to much work pulling it - something you can do pretty easily with a continental style plane.

At the risk of sounding like warren, I'd imagine if krenov needed to do more than skew a plane 45+ degrees, he may have been better served focusing his time on learning to set the double iron properly. I've seen some of his planes (not those made by others) and they do have a second iron in them, but I haven't seen pictures of him using them nor read anything of his in entirety.

I do adhere to the cast iron flipflop issue below, though, and that's one of the reasons I ditched my BU planes. If there is a case for individuals pushing down too much on a stanley plane, and not enough forward, that's more of an amateurish problem (getting tired and leaning on the plane and exacerbating the problem). A certain amount of downforce is nice to have control over if you have a plane that is becoming dull, but not too much left to finish.

David Weaver

12-06-2013, 10:00 AM

Where things were wonkier and where specific area's needed to be precisely targeted to bring a piece into flat I found the high COE and high COG of the standard bailey style of my MF 15 to be easier to use.

This is exactly why I made the comment earlier (maybe in this thread, maybe in another one) that it's close to a wash for someone who uses a power planer, but that a BU design is less nice to use for someone prepping their stick by hand, where most of the work is done before the wood is perfectly flat. Of course, there's no rule that says you can't use both.

For the same reason derek describes a tall sail having a lot of influence (at the same time, you would have more effortless directional control if your hand was at the top of the tall sail, and more sensitivity to changes in the orientation of the mast). That is, the out of flat wood provides more feedback and is probably easier to locate. Some of that is related probably to the magnitude of weight, and some related to where it is in height off of the board.

george wilson

12-06-2013, 10:09 AM

This discussion is even more esoteric than some of the numerous sharpening threads that pop up here. I hope this makes everyone a more skillful wood worker.:)

David Weaver

12-06-2013, 10:12 AM

Well, it hasn't wandered into steel grain size yet!

george wilson

12-06-2013, 10:25 AM

My center of effort is getting off my duff and getting out in the shop!!

BTW,duff was a dessert made of flour and molasses that the sailors might be occasionally given(Oh,the great comforts of being a sailor) on sailing ships. If they were still eating their duff,and were suddenly needed pin deck,"Get off your duff" might be yelled at them.

Warren Mickley

12-06-2013, 10:37 AM

The centre of effort on a sail is that point on a sail where a large force at that point will yield the equivalent force to the sum of all the wind force over the whole sail. When I was in school we called this the center of pressure, which is a more general term for all fluids. The term centre of effort does not apply to hand planes.

When the handles on a plane are raised up a few inches (as in a wooden plane), pushing horizontally creates a small moment (rotational force) about the mouth axis, and that pushes the nose of the plane down. This is helpful when fully extending the arms while planing because the left hand can't give much downward pressure when extended. Of course many amateurs today keep their arms relatively stiff and do not extend. As I recall, Kees, you are pretty good at extending your arms. There is a small adjustment in how your hands apply force to a wooden plane versus a Bailey plane.

I soured on bevel up planes in 1976. My entire experience with Lee Valley bevel up planes is limited to about 22 seconds, just long enough to win the planing event at the Hand Tool Olympics.

Warren

Chris Griggs

12-06-2013, 10:41 AM

What I've found interesting as I've been paying attention to this this week, is that I don't find the higher COE and COG beneficial for jointer, which is where I've seen it trumpeted the most as being more advantageous. I'm actually really liking the BU on edges lately and find that for very slight tweaks in angle while squaring an edge the lowness give's me more control...also it feels more stable to me on an edge where the plane is wider than the work. It was specifically on faces where the work was almost as wide or wider than the plane that the ability to target high area's with more ease made me appreciate my BD more.

I'm glad there's no rule that I can't use both...I like having both :)

After this week I am for the first time even thinking I might like a BU jointer over a BD, because a) I really am liking the low feel on edges and because b) I like having a jointer with straight blade so the cambering advantage of the BD design is a wash in this case. I use a moderately camber 6 for flattening faces for the most part anyway and would continue to do so.

[BUT I still want first dibs if you ever sell your BD LN 7 Dave :)]

[[I agree this is getting pretty esoteric, but I think its useful when discussed in terms of how the different planes types feel and how this might make one nicer to use in one situation or the other. Of course, if one can't do what you need to with either type, the problem probably isn't the plane]]

David Weaver

12-06-2013, 10:42 AM

Ahh...welcome, Warren. I hope you decide to post here with some regularity.

Chris Griggs

12-06-2013, 10:43 AM

David Weaver

12-06-2013, 10:44 AM

Welcome to the Creek Warren. Dave has told me a lot about you. I'm very glad to see you posting here. I understand that you have a wealth of knowledge and experience. I hope you will continue to stop buy and share your wisdom.

Well, I don't know anything about warren that he hasn't said in public on other forums. I have credited warren with pushing on the double iron until the rest of us "got it".

Chris Griggs

12-06-2013, 10:47 AM

Well, I don't know anything about warren that he hasn't said in public on other forums. I have credited warren with pushing on the double iron until the rest of us "got it".

Well...yeah...I guess that's not "a lot" in terms of quantity...but it sure is in quality!

george wilson

12-06-2013, 11:07 AM

Phyrric height. It seems somewhat anachronistic that if you exceed the Phyrric height you "lose"(i.e. break the bolt). What you have achieved is not a Phyrric victory,but a Phyrric defeat,at least of your intentions.

Steve Voigt

12-06-2013, 11:09 AM

It's strange that … more emphasis would be given to the opinions of one accomplished hand tool woodworker than to generations of professionals who made a living solely by production and not teaching, many of those every bit the equal or superior to krenov in ability (unless there was something krenov was hiding).

A krenov style of plane could've been made easily, even if it would've been cutting a mortise out of a solid block, but at a time when makers and users were the most particular and had the most options (and could have made anything), the coffin smoother design was favored instead.

Exactly right.
There's an English guy who makes and sells Krenov planes with laminated soles. There's a very telling post on his blog. He talks about how he's gearing up to make a batch of jointer planes, so he's flattening his bench. And the picture shows his bench, a pile of shavings, and … a no.7 jointer plane. Now, if this guy sells his own jointer planes for hundreds of dollars, why would he use a stanley-style instead when he needs a jointer plane? Answer: because a toted plane, stanley or woodie, is far more comfortable and efficient. I believed the talk about how handle-less krenov planes were more flexible, could be pushed or pulled, bla bla bla, until I actually started using them. If you're going to plane for a couple hours at a time, a krenov is just not going to cut it.
The traditional abutment style western plane is an incredibly highly evolved piece of technology. There's a reason abutments replaced crosspins about 500 years ago--they work better. Ditto for the British style handle--it's an ergonomic masterpiece.

Oh, and welcome Warren.

Sean Hughto

12-06-2013, 11:35 AM

You've succeeded in tightening the bolt, but at the cost of breaking it. Height is tight!

Derek Cohen

12-06-2013, 11:52 AM

The centre of effort on a sail is that point on a sail where a large force at that point will yield the equivalent force to the sum of all the wind force over the whole sail. When I was in school we called this the center of pressure, which is a more general term for all fluids. The term centre of effort does not apply to hand planes.

Warren, it is an analogy. A way of explaining a process. (sigh)

When the handles on a plane are raised up a few inches (as in a wooden plane), pushing horizontally creates a small moment (rotational force) about the mouth axis, and that pushes the nose of the plane down.

Exactly what I was describing - the resistance increases as the higher handle exerts greater leverage, especially with a forward angled handle. Good or bad, the C of E creates change.

I soured on bevel up planes in 1976. My entire experience with Lee Valley bevel up planes is limited to about 22 seconds, just long enough to win the planing event at the Hand Tool Olympics.

That's not much experience of BU planes to draw such final conclusions, Warren. I am also sure that the BU planes of 1976 were rather different to those available today.

I am not sure what a local handplane competition has to do with this discussion - I do not question the value of the double iron. Indeed I promote it when I can. This discussion is about systemic features of plane design.

I was hoping for a discussion where others offer examples - descriptive or experimental - to back up their observations, not just blank pronouncements.

Regards from Perth

Derek

David Weaver

12-06-2013, 11:56 AM

Exactly what I was describing - the resistance increases as the higher handle exerts greater leverage, especially with a forward angled handle. Good or bad, the C of E creates change.

There really is no practical advantage to the orientation of bevel up planes to bevel down in terms of removing material if the issue is the distance of the hand above the sole of the plane. The rotational force warren mentions does a lot to keep the plane in the cut at the end of a stroke, but it does little to create an issue where there is a hypothetical large amount of leverage that keeps a user from removing wood with most of their energy.

In a world where plane soles are waxed, it's essentially nothing. Even without wax, the difference between the two is minimal unless a user of a bailey plane or an older plane intentionally pushes down hard on a plane instead of forward, which is, as I described previously is an amateurish mistake.

Derek Cohen

12-06-2013, 12:13 PM

There really is no practical advantage to the orientation of bevel up planes to bevel down in terms of removing material if the issue is the distance of the hand above the sole of the plane. The rotational force warren mentions does a lot to keep the plane in the cut at the end of a stroke, but it does little to create an issue where there is a hypothetical large amount of leverage that keeps a user from removing wood with most of their energy.

Hi David

I am not sure if I understand you - I associate "rotational force" with torque. Are you referring to forward motion? If so all planes do this, BU or BD. I was referring to how one puts the brakes on in Warren's example.

In a world where plane soles are waxed, it's essentially nothing. Even without wax, the difference between the two is minimal unless a user of a bailey plane or an older plane intentionally pushes down hard on a plane instead of forward, which is, as I described previously is an amateurish mistake.

Yes, of course you can reduce the friction this way. I assume that we all do it this way most of the time. However this does not alter the fact that friction is increased with the systemic change. This is a theoretical discussion - yes?

Regards from Perth

Derek (now off the bed - 1:00 a.m. here)

Steve Voigt

12-06-2013, 12:17 PM

Hi Kees

What you need to do is take two wooden planes, both with the same bed angle, one where you push from high up (a coffin smoother) and the other where you push from lower down (a Krenov smoother), and compare which is easier to push and has more control.

http://www.inthewoodshop.com/ShopMadeTools/Planesforthe2013PerthLNToolEvent_html_6425be00.jpg

http://www.inthewoodshop.com/ShopMadeTools/Planesforthe2013PerthLNToolEvent_html_3aef626c.jpg

Krenov was adamant which was the better design (not just the easier to build).

Hi Derek,
I do appreciate this discussion. Just one more point.
Your comparison between the two planes above is not quite fair, because of the design of your coffin smoother. If you look at a true 18th c. design, like the one shown in this diagram (http://kapeldesigns.blogspot.com/2013/04/wooden-smoothing-plane-plans.html), you can see that the heel is rounded in two planes.* Yours has a pretty hard edge in both planes. Aside from being more comfortable (and not leaving a big red ridge in your hand), the rounding has a pronounced effect on the direction of force, particularly the rounding shown in the upper left view of Caleb's diagram. Since it's a radius, we can apply force at almost any angle, from near-vertical to near-horizontal, just by shifting where on the radius we push. In practice, this is something we don't even think about--our hand naturally finds the most comfortable position.
I'd encourage you to reshape the back of your coffin smoother and see if this doesn't completely change how you feel about this plane. As it happens, I've made two coffin smoothers, one where the back is shaped like yours, and one with aforementioned radii. It is a world of difference. I'll try to post pics later.

- Steve
* Edit--"planes" as in geometry, not tools.

David Weaver

12-06-2013, 12:18 PM

I guess I lose interest where theoretical doesn't materialize in any material way at the bench. The cast iron flip flop vs. the tippy sailboat has more influence on who choses which type of these planes than does anything to do with friction or the efficiency of the % of push that makes it through the wood.

Chris Griggs

12-06-2013, 12:30 PM

The cast iron flip flop vs. the tippy sailboat

If SMC has a "like button" I would click it in regards to this post. Best BU vs BD analogy ever...and it really gets to the heart of one of their major differences.

Although I don't recommend going sailing in a tippy sailboat while wearing cast iron flip flops.

Zach Dillinger

12-06-2013, 1:01 PM

The cast iron flip flop vs. the tippy sailboat

Phrase of the year, right there.

Graham Haydon

12-06-2013, 1:36 PM

Why is a low coe a good thing? Is this not something we adjust on the fly bevel up or bevel down with natural changes in handpressure on knob and tote? I have yet to find an issue with the tote postion of a conventional wooden or metal plane. Thanks for the link to Caleb's coffin smoother plan btw, another item to add to the project pile :). Also, I don't find myself dogmaticly holding a plane in one fixed way. For those text book tasks and for most of the time sure, and it feels very comfortable to do so. But they also get pulled, hand pressure adjusted at the tote, sometimes dropping a hand low onto the back of a wooden try plane to suit the senario. Most of the bevel down planes will never have the ultimate scrutiny of having to earn their keep in a tradtional setting. That's not to say they are not appropriate or in fact better suited to some tasks. I just feel the low coe advantage is not something I can indentify with.

Kees Heiden

12-06-2013, 4:00 PM

Lots of very interesting things posted in this thread. Let me add some random thoughts.

The only reference I could find for CEO in sailing is the forward-backwards balance point of the sails. Not up or down. This influences how the boat steers under windpressure. It really is not very translatable to handplanes, but it is a nice catch phrase when you think about how a plane behaves under your hands. To keep with the analogy of the sails, the center of effort in a plane would be the force vector of your hands pushing against the handles.

That brings me to another point. You push your plane with TWO hands. Until now only one hand has been discussed. The importance of the second hand is immediately obvious when you try to flatten a board with one hand. (On a blockplane you only use one hand, but even then you use that one hand at the back and at the toe, one hand does the job of two.) The second hand does a bit of pulling/pushing but also presses the nose down to keep the blade in the cut.

So what is wrong with a tote which gives a bit of rotation forward to the plane? Warren allready had an example where this is in fact advantagous. In fact during a stroke you modulate the pressure on the front end of the plane all the time. Heavy on the start, lighter at the end. And on every undulation of hardness in the wood you automatically adjust the pressure back or forth too. It's too simple to think that any pressure on the front leads to more friction and is thus undesirable. It's way more complicated then that.

High or low CEO. Why would a low CEO give you more feedback from the wood? What does it do exactly, or what kind of feedback do we want from the wood? The example from Chris about prefering a BD plane because the higher centre of gravity accentuates the undulations in the wood contradicts this idea. The same could be said about a tote on top of a wooden tryplane. Any undulation in the wood, or hard to soft transition would be amplified until it reaches the hands of the user. I still fail to understand what kind of feedback a handle close to the edge gives.

Something else all together. When I see these two pictures of the wooden coffin plane and the Krenov I see the oposite of what Derek sees. I see a hand pushing the coffin from behind with a more forward force vector. On the Krenov I see a hand pushing down on that sloping back edge, pushing the plane down. (I also see hand fatique on the Krenov, because of the tense grip to keep that shape under control).

I still struggle to see the difference between CEO of a BU or a BD plane. Handles in the same position, very low on the plane. The upright handle of the LV is a typical LV thing, not especially a BU feature.

In the golden age of the wooden handplane, very tall jack/try/jointer planes with handles as close as possible to the blade were the norm. The handles were also offset to the right side. Why was that? Later the handles moved backwards. On the Continental planes to the extreme butt end of the plane. Why?

Overall, I really have no idea. Complex subject for sure. The CEO is not constant during the cut, and it's still a mystery to me what the different directions of force accomplish in a plane.

Sean Hughto

12-06-2013, 4:15 PM

I would submit that there is less difference in using my respective BU or BD jacks for the same swipe on the same panel face for example than there is between using either one with a dulling versus freshly sharpened blade. And minor differnces in handle shape, for example. would likewise have a greater effect on my use experience than the blades bevel orientation or seating. Quite simply, I question whether there would be any "there" there that matters when you reach the end of your CoE quest.

Kees Heiden

12-06-2013, 4:41 PM

It's esoteric indeed. We got quite far in understanding the handsaw, the influence of the hang of the handle, the canting of the blade, the influence of sharpening angles, he weight of the spine. So why not seeking the same kind of understanding with planes? At the other hand, when the saws are sharp, they all cut. And small changes in these aspects are hardly noticable. Only the extremes are very obvious to anyone.

george wilson

12-06-2013, 5:06 PM

I ought to build a plane with sails. Instead of having a centerboard,it would have a plane iron. Then,maybe I could begin to find where the center of effort is!!:)

This thread reminds me of the "non randomness of random lapping machines" thread. I got pestered for days after stating that the thread was not important enough to worry about.:) Hopefully,this thread's posters are more reasonable types.:)

Patrick Bernardo

12-06-2013, 5:43 PM

I'm guessing (and hoping) that Kees did that on purpose. At the very least, I'll sometimes do that to my students (I teach high school). Some kids get so angry when they mention Captain Kirk and I say, "Oh, who watches Star Wars anyway?" It's fun.

Also, this discussion has been interesting for me, a self-professed 'amateur' who probably makes all the 'amateurish' mistakes you all are talking about. In all honesty, the discussion of the forces involve help me to visualize what I want to be doing with the plane.

Adam Petersen

12-06-2013, 5:46 PM

I love it when I learn something new. This thread has provided me with lots of "new" so thanks for that. Pyrrhic Height is new to me, but I love it. C of E is also an interesting concept for me to read about. I doubt much of this is going to teach me how to be a better woodworker, but that's not my only reason for visiting these sites. I get to hear discussions of this nature, things I'd never hear at my work. At it's heart, E of C, C of E, E = MC2....it's just personal preference right?

Or maybe it's bench height...........

David Weaver

12-06-2013, 5:55 PM

Brian Ashton

12-06-2013, 7:25 PM

Well, since you brought relativity into this, I guess we could hypothesize about what types of planes work better in other universes in the multiverse.

Or, maybe "I hear only irons made out of the iron at the center of a star can match pmv11."

Or.."try the new pmv11 irons. Better all the way down to the quarks so you can plane without quirks."

:)

Maybe you can suggest that to Rob Lee that they need to commission a study on the space lab… Do you think NASA would allow a metal furnace to be fired up on the space lab.

You also have to wonder how much gravity will affect the whole process… i.e. is planing on jupiter better with BU or BD. Or do you need to wear lead shoes to plan oak on Pluto, but not when planing pine...

Do you think they had these sorts of discussions 200 years ago regarding woodworking tools?

Brian Ashton

12-06-2013, 7:27 PM

I was hoping for a discussion where others offer examples - descriptive or experimental - to back up their observations, not just blank pronouncements.

Regards from Perth

Derek

You haven't learned yet have you… You're one of those sad eternal optimists aren't you ;-)

Derek Cohen

12-06-2013, 8:11 PM

Good morning Brian

Sad? I hope not? Eternal? Hopefully. Optimist? Definitely.

Here's an example: It will be interesting to revisit this thread in several months time. No one here - not even those who show a knee-jerk reaction to reject the ideas - will be able to avoid paying more attention to the subtleties of using a plane, whether BU or BD, metal or woodie, long or short, high or low, handled or unhandled.

There are ergonomic factors that are better understood today than yesterday. In part this has to do with the changes of materials available today that were not available yesterday. In part this has to do with the numbers of woodworkers who have the time to theorise and design vs those who only did it for a living. There are many now building tools that yesterday were considered beyond their ability - amateurs building infill planes, hand saws, marking gauges ... the list is endless. None of the ideas here makes the planes of old out-of-date or will replace techniques of woodworking. It just services to refine or add to this body of knowledge.

One of the thoughts I have is that, for optimal function, there could be a range of handles with different angles to fit different lengths of planes. For example, I imagine that the longer a plane body, the more upright the handle might become. Now I am not suggesting that we manufacture such, or that we replace all the handles we have, because replacing everything could be both impractical and expensive. This is a theoretical discussion on tool design. I expect the topic to bring out those with leanings in this direction, those who are interested in ergonomics. For anyone else it would likely come across as irrelevant. Onto the next thread ....

Regards from Perth

Derek

James Taglienti

12-06-2013, 8:23 PM

Do you think they had these sorts of discussions 200 years ago regarding woodworking tools?

I think they were too busy actually making things.

Sean Hughto

12-06-2013, 8:35 PM

Derek Cohen

12-06-2013, 8:46 PM

In December 1813, the British and their allies were invading the US. I believe they took Fort Niagra. But I'm guessing the woodworkers among the soldiers in the War of 1812 prolly sat around the bivouacs talkin bout how their planes might be improved. Just stands to reason.

Sean, some of the woodworkers probably went into a huddle to do just that. :) The Aussies probably chopped up all available wood, started a barbie and brought out the beer. :)

Regards from Perth

Derek

Winton Applegate

12-07-2013, 12:16 AM

Why everyone knows that it is the vector and amplitude of the force line projected through an axis of linear motion. In the case of the hand plane, for example, it would equal the vector of force in a downward and forward orientation required to propel a blade through the wood medium and remove a given volume of the wood - i.e., a shaving of a certain size. The amplitude of the force - how many joule of energy you must produce is coupled with this angle of effort in a formula that yield a numeric representation of the work done which is called a centre or effort (or in the US: center of effort - also sometimes " uni-maximal pyhric height" or "umph"). Glad I could help.

Sean,

Poetry . . . sheer poetry.
. . . but wrong. ( I'm kidding . . . for the most part).:)

This is what he means (or should mean) by "centre of effort".
Fast forward through the chanting if you are a gotta have it yesterday westerner otherwise enjoy.
http://www.youtube.com/watch?v=6BuvZRIDmI4
http://en.wikipedia.org/wiki/Dantian

Now if you mean Center of Effort . . . well that is something else entirely . . . I have no idea what that is. Stick to the centre that's my advice.

PS: Queenmasteroftheuniverseandbabybunnytrainer has had a chronic hand ailment involving her thumb joint and tenons for the last six months or so. It was just getting worse. As far as she can figure from reading on line she has a version of "Game Keeper's Thumb:
http://en.wikipedia.org/wiki/Gamekeeper%27s_thumb.

I demonstrated some basic Tai Chi and Qi Gung movements that she could try. She has been doing them several times a day for the last week or so and . . .
. . . are you ready ? . . . . her hand is healing.

Adam Petersen

12-07-2013, 7:01 AM

So.....is centre of effort affected by the differences in gravitational pull located throughout the planet due to lattitudinal rotation and spherical shape? If a Bevel Up has a lower centre of gravity and is used at the poles versus an equatorial location do you think it would operate even better? It would stand to reason, therefore, that the elves in Santa's workshop likely perfer bevel up handplanes. (And higher benches. And lower shipping rates from Lee Valley since they are likely one in the same.)

george wilson

12-07-2013, 9:31 AM

I have game keeper's thumb,too,but it isn't from keeping game. It is from playing finger style guitar since about 1954. Hurts like blazes. First joint to always wear out on the hand I am told.

Sean Hughto

12-07-2013, 12:32 PM

You know a web site once told me that my "porn name" would be Dan Tien! I get it now.

Glad to hear about QMUBBT.

Brian Ashton

12-08-2013, 2:17 AM

Kees Heiden

12-08-2013, 3:19 AM

I hope my critical position isn't seen as a "knee-jerk reaction". It interests me just as well. I certainly don't agree with everything Derek says, but I don't have the right answers either.

BTW, I don't think the old guys didn't have the time or the interest to adjust the ergonomics of their tools. They knew instinctively (through experience) what worked and what caused injury. Injury was fatal for their existence. And maybe it was for a lage part about body positions to make the tool work as efficient as possible.

My personal problem is golfers elbow. When I have a lot of handplaning to do it tends to flare up. I don't know a solution for that either.

Derek Cohen

12-08-2013, 3:51 AM

Sorry to hear about the golfer's elbow Kees. I associate that with overuse. Rest is the best cure (I know you didn't want to hear that!).

My comment was not aimed at you. In fact, this is your thread, not mine. I just replied to your question. "Knee jerk" as in impulsive. My comment was aimed at the schoolboys who, when they do not have answers and must still be heard, decide to become the class clowns. I thought (hoped) that SMC was past this level of adolescence.

Regards from Perth

Derek

Kees Heiden

12-08-2013, 4:38 AM

Derek Cohen

12-08-2013, 6:23 AM

A bit of clowning around doesn't hurt, and you don't need to read it.

I am afraid, without actually meassuring forces and resistances and without biological knowledge it's hard to make progress. Either that or trusting our intuition.

Actually Kees, I found many of the comments insulting and demeaning. I must have missed it being clowning around.

As you recommend, next time I won't read the posts.

Regards from Perth

Derek

jamie shard

12-08-2013, 7:47 AM

To me, the COG/COE idea is basically the same thing as the "hang" of a saw tote. At the extremes, your push is going "over" or "past" the point of resistance (a plane tote that is vertical or saw handle that is more horizontal) or it is going "into" the point of resistance (a forward angled plane tote or saw handle). If you draw a line from the center of your push to the center of the resistance, "a low COE" is a small angle (less downward force) and a "high COE" is a larger angle (more downward force). So simple! :) The complication comes in from anything having a small amount of friction will seem similar to a low COE, although the actual angle might not be small. So a LV BU Smoother with a waxed sole and sharp blade will feel like it has a low COE compared to a LV BU Smoother with a unwaxed sole and a dull blade. Hopefully I've now been able to turn this into a sharpening conversation, ensuring that it will go on for another 5 pages. :D

jamie shard

12-08-2013, 7:54 AM

Ugh, I can already see how that simple statement above is crap. Carry on.

Derek Cohen

12-08-2013, 8:36 AM

Hi Jamie

No, your observation of the saw hang is spot on.

The saw hand, the height if the handle above the saw back, the rake of the teeth, the height the board (e.g. when dovetailing) is above the ground, whether one saws on the horizontal or points the blade down or up ... all these alter the way in which the saw will work. I touched on this when reviewing the Gramercy dovetail saw: http://www.inthewoodshop.com/ToolReviews/GramercyDovetailSaw.html

Regards from Perth

Derek

Mike Cozad

12-08-2013, 9:51 AM

Steve Voigt

12-08-2013, 10:06 AM

Actually Kees, I found many of the comments insulting and demeaning. I must have missed it being clowning around.

As you recommend, next time I won't read the posts.

Regards from Perth

Derek

Well, I gave what I thought was a serious, if critical, response regarding your two smoothing planes. I'm sorry if you found it insulting; that was not my intention.

Sean Hughto

12-08-2013, 10:19 AM

Yes yes one must be deadly serious at all times in discussing matters such as this, even with friends in an informal atmosphere. I'd liken this effort to better define the "hang" of hand planes to a modern Manhattan project - our world will be a different place if we succeed.

More seriously, I hope you start a revolution. I hope you make ergonomic breakthroughs that I can benefit from in my shop. I will admit to some skepticism, however, mostly because planes, like saws have been around for thousands of years. They have evolved in the hands of craftspeople who used them a lot more every week than any of us hobbiests do. Plus others have tried and not brought any meaningful improvement to the table. I won't name companies as that would be another ball of wax, but no doubt you have seen very expensive "new" plane designs out there that are no improvement on models from 150 years ago. Indeed, many of the best saws now are those that show the most fidelity to the old ones - from thin plates to tapered to handle styles.

Shwarz and Chernubi among others often find studying historical learning a much richer vein than trying to reinvent the wheel.

I am a child, please forgive me.

Derek Cohen

12-08-2013, 10:22 AM

Hi Steve

I did not find your comments insulting. Your posts about the coffin planes was good. (Incidentally, I realised shortly after the photo of my coffin plane was taken that the rear needed to be rounded). I shall answer to this separately. It is late now. My apology for not doing so before. The reason I did not do so before is that the thread was derailed at that stage.

Regards from Perth

Derek

Kees Heiden

12-08-2013, 11:03 AM

I'm a complete noob and dummy in the hand plane world. I used my SMC aquired planes on a project for the first time this past week. I did many searches and read recommended books from the library and watched instructional videos. All of this leads to my (probably stupid due to inexperience) question.

In 2 videos I watched, Japanese craftsmen pulled their planes rather than pushed. Most, if not all, comments here reference pushing and even mention tote height or angle have effects on COE. How does this discussion apply to a plane that is pulled? The 2 planes in the videos didn't have totes.

Apologies if the questions are stupid and or irrelevant. Too new to hand planes to know....

No not stupid at all! Japanese workmen also like to sit down on the floor when they work on smaller scale stuff. A pull plane is a very good idea in that situation. Personally I think you can use more force when you push, throwing your own weight over the plane. But when you sit down, that is not very relevant. Maybe it would be the prefect cure for my elbow problem. Pulling looks like it puts less stress on my ligaments.

Derek Cohen

12-08-2013, 11:48 AM

In 2 videos I watched, Japanese craftsmen pulled their planes rather than pushed. Most, if not all, comments here reference pushing and even mention tote height or angle have effects on COE. How does this discussion apply to a plane that is pulled? The 2 planes in the videos didn't have totes.

Hi Mike

Breaking down the Japanese planes, the points of note are:

* low body
* low bed and cutting angle (generally around 42 degrees)
* mouth is set far back on the body

Overall, the construction of these planes have a low C of G. How to determine the C of E? I have but one Japanese kanna, and have not used it in a while. My understanding of a kanna in use is 80% (or more) downforce and pulling on the front of the body (towards the toe) and 20% (or less) guiding the plane with the other hand. That is a lot of working down from above, rather than working low and horizontal. In other words, the C of E is quite high. When I look at some of the videos of Japanese craftsmen pulling a kanna, they seem to be straining a lot more than one would expect.

Edit to add: I visited Wilbur in December last year and played with his kanna in his shop at home. I quite quickly gave up and found it easier to push them. They worked just as well that way!

Regards from Perth

Derek

Pat Barry

12-08-2013, 12:35 PM

It seems to me that the center of effort for a plane or hand tool is something that is perceived relatively quickly by the user and may in fact, for planes for example, depend on the sharpness of the blade, blade angle, amount of cut desired, type of wood being worked, end grain vs long grain, with the grain or against it, etc. After a few passes it becomes apparent that the center of effort is the position whereby the greatest work can be accomplished with the least effort. If the effort level is too high, the bite is too much. From a physics perspective it is that combination of the two force vectors (downward and forward) that accomplishes the task at hand most effectively for the desire amount of effort the operator is willing to put forth. So its a perception not a physical thing and therein lies the difference between the center of gravity and the center of effort.

Winton Applegate

12-08-2013, 6:16 PM

but has been hard to keep up the pace. Ha, ha, ha,
So I figures I would lay one big one to the lot.
Not really much preaching just short responses. Derek expects more than childish humor so I been working up a big wad.

I couldn't wait for this one to do that one though.

That's not much experience of BU planes to draw such final conclusions, Warren. I am also sure that the BU planes of 1976 were rather different to those available today.

Hey somebody 's paying attention.
Mr. hand plane or not I expected a little more objectivity.

Be interesting if Warren winds up going BU.

Winton Applegate

12-08-2013, 6:34 PM

The cast iron flip flop vs. the tippy sailboat
I live for sentences like this. :p

Winton Applegate

12-09-2013, 1:25 AM

Unlike the previous Hitchhiker's works, the title is not a quotation from the first novel, but taken from the third chapter of So Long, and Thanks for All the Fish (http://en.wikipedia.org/wiki/So_Long,_and_Thanks_for_All_the_Fish),[2] (http://en.wikipedia.org/wiki/And_Another_Thing..._(novel)#cite_note-2) where it appears in the following passage:

“
The storm had now definitely abated, and what thunder there was now grumbled over more distant hills, like a man saying "And another thing…" twenty minutes after admitting he's lost the argument.

http://en.wikipedia.org/wiki/And_Another_Thing..._(novel)

adolescent center of effort etc

Oh now just because I read too much Douglas Adams . . .
I plead insanity; I'm just crazy about that brand of humor.

A couple of thoughts :p now that I have actually read the responses:

Feeling like one has to push down on a BU
That may be a sign the blade is sharpened less than perfectly meaning free hand and stropped. It is of course possible to sharpen the blade perfectly free hand with a proper hollow grind, very little honed area at the edge and stropped on a quality hardish strop
but
any rounding to the back and edge in general will half way "wear" it out.
When a blade is partly taken over by wear bevel it starts to feel like you need to push down on it, then it feels like you need to advance the blade and it starts cutting again, sort of but still requires downward force.

I would say for a scrub type application expect some downward force though for cross grain I don't recall needing any.

For finer planing and finish planing if you push forward and the blade does not pull the plane down into the work then the blade is wrong some how, dull or miss sharpened.
Downward force on the front to start but from then on until the end part of the stroke where one weights the rear of the plane it is just liner force for me.
Change blades and go some more if she gets "uppity". So to speak.

switched to my MF 15 and had a the piece flat in no time. What I realized after was that with the 15, I was better able to feel where the hump was and also control the plane so that I was just removing material from the high center area. Upon reflection what I realized was that when the stock was closer to flat or more uniformly convex the LA jack was easier to use as it so easily plows through the wood and leave a uniformly flat surface.

Good one ! I suppose I am overly dependent on my long straight edge and so am able to look at the depth and location of wood to be removed using the straight edge and then remove that much roughly based on experience then use the straight edge again or flip the board over onto the bench top to judge convexitude.

I do agree with the fine feel of a first class wooden plane though. Good Stuff !

Rear handle the same for BU or BD
but you are forgetting the "need" to point one's index finger at the top of the handle when using the BD thus moving the center of some thing upward thus screwing up, I mean, changing the whole deal.

Gee from reading though I though there were a fair amount of thought out and serious input here.

subjective experience that feeling of greater forward momentum
I think it is a case where when one is lower on the rear of the handle one's forearm is more horizontal and so it is easier to get a sense of rigidity in the link between human, or biapendaged alien life form, and the plane where as the more the arm comes up into an angle to the line the plane is to travel then we introduce what , in engineering techno lingo, we call "the bendy arm effect".

the "maybe a little tighter" moment before the bolt sheers off.
Ha, ha, ha I know what you mean.
Had one of those just the other day and I spend all day with wrenches for the last forty years.
I can safely blame that one on cheep bolts but there is for sure a need for a word for that "moment".
For those who enjoy that sort of humor and word play see the little known an even less appreciated book by Douglas Adams and John Lloyd
http://www.amazon.com/The-Deeper-Meaning-Liff-Dictionary/dp/0307236013/ref=sr_1_sc_1?ie=UTF8&qid=1386536235&sr=8-1-spell&keywords=The+menaing+of+liff

more vertical handle than the Bailey pattern Stanley/LN bench plane equivalent (say, a Stanley #62, below). What this Veritas handle does is encourage one to push the plane forward

Excellent ! Well explained ! Where were you when we were talking LV totes and how many/most hate them and I found them to work well and people were throwing rocks and I was loosing consciousness and then I was buried and I came back as a newt
but
I found a time portal and so was able, in the end, to make it back to this forum but just barely and not without a fair amount of PTSD I can tell you.

Oh wait that was from that brand of chocolate that I finally had to give up. No. I'm OK. Never mind. I forgot about that.

Anyway great explanation of the effect of tote angle

The higher the frog angle the greater the resistance
but if you just move your chip breaker down there to within a nano-micro of an almost nothing unit then all that resistance disappears and we are in the realm of the sweet spot. Come on . . . every body that is hip knows that.

Wait that is another thread. As I recall I was pounding the table for the other team. Derek, do you help brain wash cases ? I think I may need counseling. I'm feeling a little confused right now.

the bed is closer to the horizontal
My/our bed IS horizontal. I spend most of my time sleeping on the couch though at a steeper angle.
Do I understand you correctly that if I were to use our horizontal bed, more often, that my planing would be easier ?
I would miss you guys. I tend to fall asleep from fatigue and exhaustion after a long session of typing here, (wireless key board and computer on our TV screen), and so am unable to make it to the horizontal "sweet spot".
If I go there earlier and so not here who will defend the Klausz ? Who will trumpet for LV ?
No this is a cross I must bear for the good of the young and up and coming crafts people. It is too late for us oldsters, set in our ways, unable to budge from the couch let alone an idea but . . .

I think that the original choice of handles for the Veritas BU hand planes was inspired.

Hummmmm ahhh guys . . . that doesn't sound like a Lie-Neilson paid for endorsement by Derek . . . But it's Christmas the time of universal good will.

A vertical handle is uncomfortable on a low bench as it causes the wrist to cock too much.
See that proves just how screwed up I am. I like a low bench AND vertical handles. Now I know.
I better start looking up what ailments this is causing so I will know what to look for.
Kidding . . . interesting info !
I'm kind of low to the ground to start with so that's my excuse.

The plane is less easily manipulated, which might be favorable if someone has trouble directing their plane, but the higher center provides a more agile feel for a user who intends to direct the plane.
I must say I had that in my mind to post before David brought it up. So I think he is right there.
Trade offs though like Derek said.

This discussion is even more esoteric than some of the numerous sharpening threads that pop up here. I hope this makes everyone a more skillful wood worker.http://www.sawmillcreek.org/webkit-fake-url://224ED131-BF92-4FA3-862E-B3F9AB393BD4/smile.gif

Hey it is getting tougher to find intelligent people doing/making/talking about intelligent things/subjects.
That is why I come here. Gotta find it where we can.
I got tired of people in other forums talking about what brand of snow blower they used. In a woodworking forum ? As the main topic ?

I would rather climb this mast any time. Hey, what's this ? It feels like I can steer the ship up here by tilting my head . . .
. . . no . . .
. . . no that's just the coffee talking.
Gotta lay off that Kona Gold.

I haven't . . . read anything of his (Krenov) in entirety.

Embarrassed silence . . . profound speechlessness . . .

I never now where to look in situations like this. Do you guys ?

That's OK I remember moments like this in high school when I attempted to integrate what I had just learned in biology class about organisms, over population and natural selection in a petri dish into my sociology/government classes. I learned to not do that after several instances where the whole class, including the teacher, went silent for what seemed like minutes.

I do adhere to the cast iron flipflop
That could be your magnetic personality coming through. We don't all have that.

the center of pressure, which is a more general term for all fluids. The term centre of effort does not apply to hand planes.

Warren, it is an analogy. A way of explaining a process. (sigh)

Hey the human body is like mostly water and stuff

I agree the Krenov is pretty much a finish plane though he made some longer ones. He made "a few , small, fine things" and that is the context these planes are to be viewed from and used on not for making conference tables.

For large projects in hard wood I like a handle and a front tote knob. But I use a scrub plane to so what do I know.

The traditional abutment style western plane is an incredibly highly evolved piece of technology. There's a reason abutments replaced crosspins about 500 years ago--they work better.

Explain why they , Stanley bedrock etc., never got around to putting a halfway decent wheely adjuster thing in it. The "new" Euro style adjuster in the LV BU just blows that loosy goosy spinny thing out of the swimming pool.

(I also see hand fatique on the Krenov, because of the tense grip to keep that shape under control).
Yup ! I added indentations on the sides (ala Vertas by the way)
http://i801.photobucket.com/albums/yy298/noydb1/IMG_0812_zps06dc6fc3.jpg (http://s801.photobucket.com/user/noydb1/media/IMG_0812_zps06dc6fc3.jpg.html)

I would submit that there is less difference in using my respective BU or BD jacks for the same swipe on the same panel face for example than there is between using either one with a dulling versus freshly sharpened blade.

Hence my ever present stack of sharp blades. Lock and load.
Or
in the case of bevel down : fiddle fart with little flat screw oops dropped in the saw dust again, there we go now get this extra plate thingy close to the edge oops over the edge well that probably didn't take off too much of the sharpness, pour in the black powder and the paper and tamp 'er down, OK get her in there and wheely, wheely, wheely the adjuster, is it doing anything ? OK wheeely wheely there we go aannnnnnd loaded.

What was I going to shoot, errr, I mean, plane ?

when the saws are sharp, they all cut. And small changes in these aspects are hardly noticable.
When I made my frame saw for resawing the brand new bandsaw blade just grabbed and grabbed until I changed the tooth geometry then she worked well.
When I got my brand new largest backsaws from Lie-Neilson they grabbed and bounced until I again changed the geometry slightly then they behaved. Thick purple heart dovetails but . . .

the numbers of woodworkers who have the time to theorise and design vs those who only did it for a living.
EXACTLY
Those dudes were working such long hours and not really making their own tools, I guess for the most part, chopping wood, taking care of the horses and beating the indentured apprentices for not doing same that they didn't have time to compare notes with people all around the world in real time.
me thinks.

There ! Bob ! Whew !
I finished it. What a job.
Hey were is everybody ?
Gone home?
Gone to bed ?
Sigh :(
oh well if I curupt, herumph that is I mean help just one . . . well then . . .
it was all worth it.
:)
Hope there are some coffee grounds left to make coffee before I start in on the next thread.

Kees Heiden

12-09-2013, 6:13 AM

I repeat what I once said, you're a funny guy Winton!

To answer just one of the many items you adressed. Small changes in handtool geometry I hardly noticable. I had a Mitre saw with rip filed teeth and a positive rake angle, so the teeth were pointing forward. That just didn't work. I resharpened one of the blades to a rip with a lot of negative rake angle, which was a lot better. Adding fleam, and it entered nirvana. So yes, geometry changes make a big difference. But at the other hand, I am hard pressed to feel the difference between 4, 8 or 12 degree rake angle. The more agressive ones cut a little faster, the mellower ones are smoother. But they all cut perfectly well. Somehow we adopt easilly to these subtle changes in the design of the tool.

The Germans learned to work with planes like this, it is hardly imaginable, but still they do.

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David Weaver

12-09-2013, 8:04 AM

Nothing wrong with those continental planes! I can't stand the mechanism that ECE uses to retain the iron and cap iron in the primus planes, but those planes do have some following.

Winton - you know you love those bailey adjusters!! Yesterday, when I was cleaning off my phone, I came across a video where I was adjusting a plane. I'm partial to these backlash planes, mostly because I don't do a lot more setting of them than one time and then plane until they're dull, maybe minor adjustments here and there. It looks like it took about 3 seconds for me to adjust the plane to depth.

If there is a lot of lash, I just take my index finger, put it on the wheel and then push and get all of the lash out in one shot. No grabbing the wheel and little twitches or anything, just one second or so of zipping it right out, maybe two - that's presuming the plane needs to be adjusted in the direction of the backlash, which is only true some of the time.

It sounds like the creek community will need to get you a custom cap iron and screw - a setup where the screw and cap iron have a tiny hole drilled in them and a string attached to the screw :)

Brian Ashton

12-09-2013, 8:13 AM

Graham Haydon

12-09-2013, 8:15 AM

I can only add my apologies to Derek if my response was taken as offensive. I think it must have been as I cant see many of the responses unless I log out.

Chris Griggs

12-09-2013, 8:40 AM

Good one ! I suppose I am overly dependent on my long straight edge and so am able to look at the depth and location of wood to be removed using the straight edge and then remove that much roughly based on experience then use the straight edge again or flip the board over onto the bench top to judge convexitude.

I do agree with the fine feel of a first class wooden plane though. Good Stuff !

I haven't had any absinthe this morning so I can't decode most of your post, but this part I understood.

Actually I use a straight edge also or the edge of my plane to identify convexity and concavity. I am speaking of the ability to better ride the high areas with a BD plane and bring them down. Say you have a 2-4" wide board and you are working the convex side. That same "suction" to the surface that can make a BU plane so nice when it comes to plowing through difficult grain, also makes the plane want to ride the sides of the hump rather than the apex. In addition, that flattness and less sense of "feeling" what the plane is doing makes it harder to tell if the plane is riding the apex or the sides of the convexity...so its both harder both to feel what the plane is doing and as well as actually control what it is doing in...in terms of riding the apex of a hump. I have found this to be especially true when the plane is wider or about the same width as the board. On wider boards there is enough material on either said that you can just sorta mindlessly plane plane in the center and you eventually get a hollow that you can easily than plane flat. On a board that is say 2" wide there is no material on either side of the plane for the non cutting part to ride on so if you don't ride the curve really accurately its easy just keeping planing without getting out the convexity...of course, a blade with a bit of camber also makes putting a hollow in the board like this a bit easier...so there's another point for BD (albeit a tiny easily overcome one) in this situation.

Illustration below (this is supposed to be the view from either directly behind or in front of the plane. The straight line represents the blades width. With the BD I find I have a slightly easier time telling if I am planing the highest part of the hump and am less likely to inadvertently rock to one side or the other)
276648

We are of course talking minutia here. Its not like you can't flatten out (or that its even difficult) to flatten out a hump with a BU plane. But doing so with a BD plane just feels a little more intuitive.

(say's the guy who is madly in love with his new small BU smoother...hey Winton, since you love BU planes so much you should really get this guy, it's actually a step up from their other BU planes which are quite nice in there own right. I don't care for the 4 1/2 sized BU smoother you love so much, but the SBUS I think may be one of the best planes they've designed......[this shameless plug comes to you courtesy of my wallet and last weeks cyber Monday sale])

Steve Voigt

12-09-2013, 9:01 AM

I haven't had any absinthe this morning so I can't decode most of your post…

Brilliant.

Derek Cohen

12-09-2013, 11:17 AM

Hi Winton

Wonderful post ... however next time perhaps try drinking the coffee and not smoking it! :)

There are many gems in-and-amongst your ravings. The trouble is I do not have much to add to these.

Derek wrote: "more vertical handle than the Bailey pattern Stanley/LN bench plane equivalent (say, a Stanley #62, below). What this Veritas handle does is encourage one to push the plane forward"

Winton wrote: "Excellent ! Well explained ! Where were you when we were talking LV totes and how many/most hate them and I found them to work well and people were throwing rocks and I was loosing consciousness and then I was buried and I came back as a newt"

Actually, we discussed this together on Knots 2 years ago, and were in agreement there as well.

Regards from Perth

Derek

Derek Cohen

12-09-2013, 11:44 AM

Actually I use a straight edge also or the edge of my plane to identify convexity and concavity. I am speaking of the ability to better ride the high areas with a BD plane and bring them down. Say you have a 2-4" wide board and you are working the convex side. That same "suction" to the surface that can make a BU plane so nice when it comes to plowing through difficult grain, also makes the plane want to ride the sides of the hump rather than the apex. In addition, that flattness and less sense of "feeling" what the plane is doing makes it harder to tell if the plane is riding the apex or the sides of the convexity...so its both harder both to feel what the plane is doing and as well as actually control what it is doing in...in terms of riding the apex of a hump. I have found this to be especially true when the plane is wider or about the same width as the board. On wider boards there is enough material on either said that you can just sorta mindlessly plane plane in the center and you eventually get a hollow that you can easily than plane flat. On a board that is say 2" wide there is no material on either side of the plane for the non cutting part to ride on so if you don't ride the curve really accurately its easy just keeping planing without getting out the convexity...of course, a blade with a bit of camber also makes putting a hollow in the board like this a bit easier...so there's another point for BD (albeit a tiny easily overcome one) in this situation.

Hi Chris

I don't get this. Perhaps it is too late at night.

Both the BU and BD planes will remove humps and bumps and twists and turns equally and the same. Where they differ in my experience is that the BD is used with more downforce and this creates a feeling of being the more powerful plane (as it "feels" heavier), compared with the BU, which may be used with more horizontal force and thus seems to skim lightly.

I use each type pretty equally and enjoy their differences. Since you refer to jointing, I prefer the BU. It squats down on the edge, feels more stable than the higher BD Bailey planes, and seems to offer more feedback here. I think it is due to ones hands being low when planing. By contrast, the low BD HNT Gordon Trying plane is similar when used in a manner similar to a Krenov. I added a handle to mine and it became unstable as it was now held high, and lost feedback.

Regards from Perth

Derek

Chris Griggs

12-09-2013, 12:01 PM

Hi Chris

I don't get this. Perhaps it is too late at night.

Both the BU and BD planes will remove humps and bumps and twists and turns equally and the same. Where they differ in my experience is that the BD is used with more downforce and this creates a feeling of being the more powerful plane (as it "feels" heavier), compared with the BU, which may be used with more horizontal force and thus seems to skim lightly.

I use each type pretty equally and enjoy their differences. Since you refer to jointing, I prefer the BU. It squats down on the edge, feels more stable than the higher BD Bailey planes, and seems to offer more feedback here. I think it is due to ones hands being low when planing. By contrast, the low BD HNT Gordon Trying plane is similar when used in a manner similar to a Krenov. I added a handle to mine and it became unstable as it was now held high, and lost feedback.

Regards from Perth

Derek

That was just my poor attempt at trying to illustrate that I recently realized that I have a slightly easier time removing a hump running across the width of the board with BD than BU. (the sketch is is supposed to be the view from the back of the plane...the straight line is the blade width. I think you interpreted it as a convex edge joint with the straight line being the plane running down the length. I didn't explain it well).

Anyway, I just find the the high center of gravity makes it easier to remove a hump like that, as I have an easier time sensing when I'm on the apex of the hump (again speaking about a working the convex side of a cupped board here not an edge joint). Its minute...and actually it was just something I sorta realized last week as I was switching back and for between the two a lot, and its not something I ever noticed or really thought about until last week. Its not something that I can do with one and not the other...its just that the different feels make some operations more intuitive feeling with one over the other. I can just feel the out of flatness (and in turn improved flatness) better as I'm planing with a BD plane. I imagine this is because the higher COG lets me better feel subtle rocking and undulations and better control the tilt of the plane...it is easier for me to tell/feel that I'm cutting the high area that I am intending to cut (really its just a reiteration of the tippy sailboat thing again...ironically, in this case the tippy sail boat helps me tip less and better control the tip...nothing that hasn't been said before...)

For edge jointing, for me its wash which I favor. I agree the the BU feels more squat and stable on a narrow edge, but that the BD gives me a slightly better sense of plumb...though I have been favoring my BU slightly on edges lately for the exact reason you state. I really like that low stable feeling on an edge.

Anyway, I'm talking small differences in feel here, I wouldn't want anyone to think they can't do something with one or the other...just trying to illustrate how the different distribution of weight creates a subtle difference in use that might impact personal preference. The image I posted far exaggerates the idea.

(and just to put that difference in perspective, I will say that at the end of the day Sean's statement "I would submit that there is less difference in using my respective BU or BD jacks for the same swipe on the same panel face for example than there is between using either one with a dulling versus freshly sharpened blade." is much more in line with which plane I would pick up (MF 15 Vs LA Jack) for removing a bit of cup or twist from say a 24" by 4" board. The deciding factor of what to use for such a task has much more to do with what is sharp or what is already out than any differences associated with weight distribution/blade orientation)

Kees Heiden

12-09-2013, 2:34 PM

Nothing wrong with those continental planes! I can't stand the mechanism that ECE uses to retain the iron and cap iron in the primus planes, but those planes do have some following.

Yes, that's what they say. Compare the German plane with an English model. The mouth in the German plane is almost halfway from the front. The English is at 1/3. The English handle is closer to the iron. Two quite different concepts with very different ergonomics, and still, both work.

http://www.planemaker.com/images/planes/jointer.jpg

http://upload.wikimedia.org/wikipedia/commons/thumb/3/38/Varlopes_rabot.jpg/800px-Varlopes_rabot.jpg