My new sure-fire get rich quick scheme

[Steve Voigt]

Like many of you, I regularly browse through the blogs aggregated at Norse Woodsmith. There is a lot of good stuff there, but there's also a lot of drivel.
This morning, I came across this gem, in response to a question about dealing with difficult grain:

Or you can use a high angle plane or my new favorite technology, a high angle chip breaker. As this link will show you:
http://vimeo.com/41372857, Professors Kawai and Kato dialed in the importance of the chip breaker or cap iron in producing good results even against the grain. I replaced my standard cap iron with one ground at 75 degrees and the results were very interesting.

So apparently, it's not about setting the cap iron at the correct distance--what you need is a new cap iron ground at the "correct angle." And you can't just grind your old chipbreaker--you need to get a new one, because…well, just because.

So, on to my business plan. I'm going to buy up all the old Stanley chipbreakers I can get. I'll grind a small secondary bevel, and resell them for oh, about $80 apiece. I'll guarantee that these patented high angle chipbreakers will stop all tearout (provided, of course, that you set them the correct distance from the cutting edge).

OK, I'm off now to start planning the construction of my first yacht and vacation mansion.

- Steve

[David Weaver]

Not a good business plan - I think you should sell standard angle cap irons for the people who bungle theirs by putting them at 75-80 degrees.

Of course, I know you're joking - I wonder what a thin shaving on a 75 degree cap iron would do in a plane that had a long wear - nothing good, I'd bet!

I experimented with all manners of angles (but nothing below 45 degrees) several years ago and found an 80 degree cap iron to have a very narrow working range, and a bad feel (and worse surface than a 50 degree or so stock chipbreaker). Since the video came out, I've seen 80 degrees mentioned several places, but it's better for videos and studies than it is for plane-using woodworkers. Something rounded a little in the 50 degree range seemed the nicest.

So...sell the "patented perfect amount of curve" on the cap iron, too. I'm sure the bunches who take the CS classes would get their phones at and wire the money right to you. :)

[Steve Voigt]

Yeah, I was obviously being silly, but you're right about the angles. I too have experimented with a wide range of angles, and found the same thing. At 75° or 80°, you move the breaker just a hair too close and the plane is suddenly impossible to push.

It seems to me that someone who was serious about this would start by doing a little research. There is a huge trove of information from SMC, Wood Central (your article, but also some very long threads), Wood Net, and other places. An hour of reading, followed by a few hours of experimenting, should be enough to figure out that (1) the angle isn't that important, but should probably be in the 40°-60° range; (2) the brand of chipbreaker isn't that important--almost anything can work with a little tlc; (3) the crucial thing is the distance, duh.

On the other hand, if someone's research consisted of watching the video that some blogger linked to, followed by 10 minutes of experimenting in the shop, then I guess this is the sort of thing they're likely to come up with…

[Pat Barry]

Thanks for posting the video. It is very enlightening. I suspect this sparked some discussion previously also. Material likely makes a big difference. Have they done further work to show the effect of material? It seems they are telling us that we need to factor the distance from the edge to the cap iron as well as the angle. This makes sense.

Also, does anyone know if they have more recent work with other plane blade angles?

Here was their summary (based on their testing with the 40 deg angle blade to surface)
Summary


If the blade is sharp and if the cutting depth is smaller than .05 mm (2 thou), then tear out will not occur even with a single blade
The distance of the cap iron to the edge of the blade should be adjusted according to the cutting depth.
A cap iron bevel angle of 80 deg prevents tear out more than a bevel angle of 50 deg and so the cap iron can be placed further from the edge of the blade.

[Terry Beadle]

I'm a little disappointed in they showing mostly against the grain cutting. They did show a with the grain segment but I was hoping to see how a with the grain cutting with different cap iron angle settings would affect the surface. I 'assume' from the video they went against the grain because the with the grain cutting was not affected by a high angle cap iron setting.
I 'assume' it would be smooth results and the cap iron could be in the 40 to 80 degree range with out significant affect in results.

I wonder still it that is so.

Right now all my cap irons are set to 45. I adjust my cap iron to cutting edge depending on if it's a jack plane, jointer, or smoother. Smoother is set to very close and depth of cut is set to 2 thou or less. Jack plane has cap iron set to about 1/16th to 3/32 nds. About the same in the jointer. This seems to work.

The other thing is if the grain changes direction mid work piece, I change the direction of the plane too....unless I just really roughing the work piece and not concerned about tearout.

So now that I'm thinking about my thinking, I'm thinking I might be over thinking thinking about my thinking...hoot!

[Greg Ladd]

David,

No need at all to bring CS into this thread that I can see.

There are many that value his perspectives and the fact he has helped many desire to increase their hand tool skills. He has also hand plane thousands of board feet of lumber so it is a fair assumption he has some decent level of skill and therefore, a level of experience which obviously provides a decent basis from which to educate others from.

Those that have an opportunity and choose to attend the CS classes (or training with anyone else) do so of their own free will. Woodworkers as a group should encourage learning of the craft by others, no matter the route an individual chooses. Many times in life, an instructed learning opportunity opens the door to dramatically increased learning later when one practices some newly discovered skills in private, on their own.

Please, give it a rest.

Greg

[David Weaver]

Greg, did I violate the TOS here? I didn't. If I or anyone else was looking for someone to tell them what to post or what not to post outside of the TOS rules, we would ask.

[Steve Voigt]

Terry and Pat,
I didn't actually mean to post that video--I figured most people had seen it--but I'm glad you got something useful out of otherwise snarky post. :)
I guess I need to remember that not everyone has seen and read the relevant stuff. If you want more info on the video, or cap irons in general, here are the three best sources I know:

Steve Elliott's website (http://planetuning.infillplane.com/index.html). Click on chipbreaking and read everything.

Kees van der Heiden's blog (http://seekelot.blogspot.com/). Especially check out the videos of Kees using his planes with different cb settings.

David Weaver's WoodCentral article. I'm not allowed to link to this, but if you google "setting a cap iron - woodcentral," it's the first link that comes up.

[Warren Mickley]

Tear out can occur when the cutting depth is .001 and less. It depends on the wood. The Kato study worked with only a couple of different timbers and only a few orientations. The study was designed to show how the cap iron worked, not to be a definitive guide for its use. As Peter Nicholson wrote in 1812,

The distance between the cutting edge of the iron, and the edge of the cover, depends altogether on the nature of the stuff.

As to the sales of cap irons, I think the important factor is marketing. As may have shown, good marketing can sell cap irons that are nearly useless.

[Kees Heiden]

I've got a theory why the Japanese might like a steeper bevel angle on their capirons. It isn't quite as easy to set the capiron close to the edge in a Japanese plane. You can't really see what you are doing. I guess they set it, then take a few cuts and look at the surface if tearout is still a problem, then tap it down a little deeper etc. A capiron bevel angle with more effect might be usefull in that process. In a western plane you set the capiron by sight, before inserting it into the plane. I find that it is not difficult to set it at 0.1 mm, so the bevel angle doesn't need to be so steep. With a 45 degree leading angle you can get all the effect you want, even for quite demanding types of wood, if you set it that close.

BTW, in the Kato article on Steve Elliotts webpage you can read that a capiron with a 50 degree bevel, set at 0.15mm from the edge gave the best performance on their piece of wood.

[Warren Mickley]

I've got a theory why the Japanese might like a steeper bevel angle on their capirons. It isn't quite as easy to set the capiron close to the edge in a Japanese plane. You can't really see what you are doing. I guess they set it, then take a few cuts and look at the surface if tearout is still a problem, then tap it down a little deeper etc. A capiron bevel angle with more effect might be usefull in that process. In a western plane you set the capiron by sight, before inserting it into the plane. I find that it is not difficult to set it at 0.1 mm, so the bevel angle doesn't need to be so steep. With a 45 degree leading angle you can get all the effect you want, even for quite demanding types of wood, if you set it that close.

BTW, in the Kato article on Steve Elliotts webpage you can read that a capiron with a 50 degree bevel, set at 0.15mm from the edge gave the best performance on their piece of wood.

The Kato study says (figure 12) that a capiron with 80 degree bevel set 0.3 from the edge gave a good surface also. I have used a capiron with rounded bevel since 1975: this is what Peter Nicholson described in 1812.

[Winton Applegate]

For most all wood, figured, reversing, rowed what have you, through more than ten minutes of experimenting I can assure you, I have found the perfect chip breaker placement and the angle as David said can be left stock.


I take the chip breaker in hand, carefully carry it across the room and wedge it under the door to hold the door open.


Then select a bevel up blade with a 45° sharpening bevel, even an old 40° will do for about everything under the sun. I mindlessly slap it into the bevel up plane,

even an old stock (no filing or fettling) LN BU Jack will do in a pinch

push the plane along the wood while advancing the blade until it starts to bite, change the tilt until the cut is centered on the blade, I push the plane and keep turning the depth further and further until I fart , back off a bit so the effort is a bit less and I have my maximum depth of cut.

I don't even have to walk across the room and change the setting of the chip breaker under the door; it seems perfectly content there and seems in no way to have any effect on the depth of cut. Believe it or not . . . it is true.

Plane until dinner time or the work is finish.

Back off the depth and finish plane. See comments above on CB.
No squinting at thousandths of an inch gap judgments.
Absolutely no freaking throat jamming I had never even paid attention to the word wear until I started watching this bevel down micro setting breaker “stuff” .

It did help me tune the Japanese scraper plane I recently bought for screwing around with but I would have filed it even if I didn’t know what it was called I was filing . . . and reached for the bevel up when I had some serious planing to do.

Funny thing . . . the Japanese scraper plane does not have a chip breaker either and it planed one of my unmentionable, purple colored, chipout prone woods with no tear out with a stock factory sharpened blade that wasn't all that polished.
Hmmmmm
no chip breaker, Japanese bevel down plane, no tearout and a healthy thickish ribbon.
. . . hmmmm
no chip breaker, Japanese bevel down plane, no tearout and a healthy thickish ribbon.
. . . hmmmmm

I'm thinking, I don't have to keep thinking about thinking . . .
Thanks Terry I enjoyed that.

So the best setting for the chip breaker is at least twenty feet from the work bench. In my shop at least. YMMV.


PS:
Ah yesssss
a little silliness
always desirable around such a serious subject.


Of course I couldn’t avoid contributing. I really did try.
I hand cuffed my self to the radiator with the wireless key board well out of reach.


After that all I recall is darkness accompanied by the sound of wild thrashing and clanking . . .
oh and there was another more distant sound . . . like a wild beast howling.


When I came to I found I had made a post on this thread.


Sorry
I did try to stop the beast but he was just too much for me.

[Kees Heiden]

The Kato study says (figure 12) that a capiron with 80 degree bevel set 0.3 from the edge gave a good surface also. I have used a capiron with rounded bevel since 1975: this is what Peter Nicholson described in 1812.

This article: http://planetuning.infillplane.com/html/review_of_cap_iron_study.html
I don't see a figure nr. 12?
At the end of the first part, they write in conclusion 9 that the best wear profile resulting in self sharpening was with a 50 degree angle set at 0.1 mm from the edge. At 0.2 mm from the edge the capiron had the least amount of wear.
So in the second part of this study they used a 50 degree bevel at 0.15 mm, because of the wear characteristics of blade and capiron.

[Warren Mickley]

Kees, I was referring to to this study on Steve Elliott's website.
http://planetuning.infillplane.com/html/chipbreaker_study.html

This study was widely discussed on the woodworking forums in 2007-2008. People who did not read it carefully came up with the erroneous statement that the cap iron had to be within .004 inches to have an effect. The naysayers long used this error to proclaim the impracticality of the double iron system.

I think the wear study is less significant because it only studies the wear after planing 600 feet of material. A trying plane or a smoothing plane has lost its ability to produce a fine surface long before this point. It is like arguing about the taste of various week-old loaves of bread. For myself, the only plane I would ever use this much without sharpening is a jack plane, in which case I would not care so much about surface quality.

[Pat Barry]

At the end of the first part, they write in conclusion 9 that the best wear profile resulting in self sharpening was with a 50 degree angle set at 0.1 mm from the edge. At 0.2 mm from the edge the capiron had the least amount of wear.

I'm sure that the article is not referring to the wear of the cap iron. They are referring to the wear of the blade itself. The actual statement was:
"The best wear profile, resulting in self sharpening, was found at a cap iron distance of 100 microns (0.004”) and an angle of 50 degrees. The most shallow wear on the blade face was at a cap iron distance of 200 microns and an angle of 50 or 60 degrees."

[bill howes]

I believe the term used in logic for your argument is reducto ad absurbum, which seems to be a valid response to the chipbreaker research.
Can someone explain why an edge at 50 degrees bevel up (12 1/2 + 38) is any better than 50 degrees bevel down (York pitch)?
Anything to do with the blade edge being closer to the trailng edge of the mouth for support?

[Kees Heiden]

Thanks for the link Warren, I forgot about that article.

Personally I don't think the ideal capiron bevel angle is that important. It is good to realise that a steeper angle increases the effect of the capiron. But it also increases the chance to set it too close to the edge, so the shaving is worked too much, pushing force increases a lot and the wood surface suffers. Hard to do that with a 45-50 degree angle on the capiron. For me, and the kinds of wood I use, 40 to 50 degree is plenty. I also have no problem setting the capiron at 0.1 mm (4 thou). And I have measured the distance a few times with a microscope, so I am pretty sure about that.

Indeed, the variations in edge wear are pretty minimal in Kato's articles. When I look at the force diagrams in the above referenced Kato article, then I think the slope of the curves is almost identical and any deviations are probably from measurement errors.

[Kees Heiden]

Can someone explain why an edge at 50 degrees bevel up (12 1/2 + 38) is any better than 50 degrees bevel down (York pitch)?
Anything to do with the blade edge being closer to the trailng edge of the mouth for support?


Good question, Anyone has an answer?
The big difference between these two is the clearance angle. The bevelup has only 12 degrees of clearance angle. When you sharpen the york pitch plane at 30 degrees, you get 20 degrees clearance angle. Because loss of clearance angle is an important apect of blade wear, I suspect less clearance angle is not such a good idea in the long run. But I do not really know, just conjecture.

[David Weaver]

I believe the term used in logic for your argument is reducto ad absurbum, which seems to be a valid response to the chipbreaker research.
Can someone explain why an edge at 50 degrees bevel up (12 1/2 + 38) is any better than 50 degrees bevel down (York pitch)?
Anything to do with the blade edge being closer to the trailng edge of the mouth for support?

I don't think that plane for plane and mouth for mouth that it's really any different (BU or BD at 50 degrees). If you're using a thin single iron, I guess there is some chance that the plane iron bedded at 12 degrees is stronger because it's like pushing a broomstick at 12 degrees rather than putting a force at the end of it while holding it at 45 degrees to that force.

But, it's a personal preference thing if the other aspects of the plane are the same. Some folks like the BU planes (iron and no cap iron, moveable mouth, in the new ones there are setscrews etc, different adjuster) and some like the BD better (easier to camber and keep cambered, thinner iron, different adjuster, cap iron).

[Kees Heiden]

I don't think that plane for plane and mouth for mouth that it's really any different (BU or BD at 50 degrees). If you're using a thin single iron, I guess there is some chance that the plane iron bedded at 12 degrees is stronger because it's like pushing a broomstick at 12 degrees rather than putting a force at the end of it while holding it at 45 degrees to that force.



Personally I don't think that makes a difference at all. The blade is tightly bolted to the plane, and you are pushing the plane, not the blade.

[David Weaver]

There does seem to be a little something to planes that are BU and bedded properly (in feel) where the iron is just bedded at both ends and at the very cut line. But it's a perception thing and not a practical difference maker in woodworking.

It goes back to the discussions we've been having lately, it's often experience that's lacking and great tools with lacking experience can't come close to just OK tools even with mediocre experience.

[Pat Barry]

What I am learning here is that for a BU plane, the cap iron serves no purpose related to actually planing the wood and reducing tearout. That is with regard to the previous discussion of setting the cap iron a mere few thousandths of an inch from the blade edge. Or am I wrong about that? Can you set a bevel up cap iron within a few thou of the blade cutting edge? What I have seen is that the cap iron rests on the top surface of blade, not on the bevel. Maybe I'm misunderstanding this.

[Bill Houghton]

What I am learning here is that for a BU plane, the cap iron serves no purpose related to actually planing the wood and reducing tearout. That is with regard to the previous discussion of setting the cap iron a mere few thousandths of an inch from the blade edge. Or am I wrong about that? Can you set a bevel up cap iron within a few thou of the blade cutting edge? What I have seen is that the cap iron rests on the top surface of blade, not on the bevel. Maybe I'm misunderstanding this.
I believe the action occurs in the first few fractions of an inch from the cutting edge. The cap iron/lever cap on a bevel up plane is too far away. Instead, the action occurs on the bevel. This is why some people keep multiple (cutting) irons for their favorite bevel up planes, each ground to a different angle. This creates an effect similar to that of setting the chipbreaker at different distances from the cutting edge on a bevel down plane. My 2.0467 cents, adjusted for inflation.

[Winton Applegate]

Why

Time for an analogy or two.
and some humor.
and keep in mind I came at things from the extreme end. Very hard wood that chipped with bevel down and chattered and skipped when the soft blades got dull quick. I suppose if you like extra metal things to play with and softer wood then . . .
All that was solved with BU.
I find NO reason to go backward just because I happen to plane some walnut rather than the purple heart and bubinga.

anyway . . . my response :

12° is plenty of clearance
unless
in my opinion
some one, NOT ME FOR SURE, starts fooling around with “the ruler trick” and or stropping the back side and or tilting the blade up to “hone” the worn edge back into sharpness

if some one were to make those MISTAKES then the clearance angle is closed up more than some realize. I did it. I am not making this up. I read all that stuff ten years ago AND DID IT.

Those are mistakes.
I rejected them when they failed to produce clean and easy and effective results.
I won't argue them. I have too many times.

as opposed to SHARPENING the edge which involves power grinding the bevel OR as I do going to say a 300 stone or even 220 or 120 to cut the wear bevel off and then sharpening forward from there to the fine stones (at least 6000).

Never doing any touch up honing.

IF THAT IS DONE then 12° clearance is plenty.

Some could argue, rightly, that a bevel UP with lots of camber is less effective.
I would some what agree
but
when I get in that ball park
these days (in the old days I just cambered the hell out of the bevel up and jack planed to my heart's content. Not a big deal really. It is just that the scrub is even faster but kind of a pain in the butt to sharpen; more so than the BU but stays sharp longer cross grain.)

I just use my LN bevel down scrub. In some of the extreme woods I back bevel the scrub blade but that is a whole other rat hole.


Why use a bevel up rather than a bevel down if the effective angle is the same ?
SIMPLICITY
Better blade adjuster response.
Better blade support (as you said).
and
No jamming in the throat from the purposeless, thick, round nosed, spring shaped pile of _____ metal in the way of getting shavings out of the throat.

The opportunity to be obstinate and a pain in the neck in the forums.
:D
The opportunity to use the Varitis wide bevel up smoother which in its self is worth the price of admission and rejection by the majority of the chatroom dudes.
;)

It feels kind of like being the first guy in town with an automobile and every body else is riding horses and using horse drawn buggies and telling me how silly I am.
and how much better the horse is
and how the automobile is just a toy and a passing fad or fancy.

I say HA !

I did the Horsey thing already and still continue to monkey around with horseys but when I want to go some place in the cold and rain and dark . . . for fifty miles . . .

Well . . . guess which I choose.
Old Paint stays snug in the barn.

Its geeeter done
or
fool around with horsiness, and slowness and lameness and tiredness and feed and water and harnesses.

Nah dude, nah

BU . . . Oh yah !

[Winton Applegate]

Pat,


Can you set a bevel up cap iron within a few thou of the blade cutting edge?

Before you dot another i or cross another t, Bob Cratchet,
go to your web browser and order one of these
http://www.leevalley.com/US/Wood/page.aspx?p=67691&cat=1,41182,52515
All will become clear.
You will become a new man.
Your hair will begin to fill in and your energy will be boundless . . .
in the shade of the eternal bounty and fruitfulness that is

BU

[Derek Cohen]

http://www.sawmillcreek.org/images/misc/quote_icon.png Originally Posted by bill howes http://www.sawmillcreek.org/images/buttons/viewpost-right.png (http://www.sawmillcreek.org/showthread.php?p=2263014#post2263014)
I believe the term used in logic for your argument is reducto ad absurbum, which seems to be a valid response to the chipbreaker research.
Can someone explain why an edge at 50 degrees bevel up (12 1/2 + 38) is any better than 50 degrees bevel down (York pitch)?
Anything to do with the blade edge being closer to the trailng edge of the mouth for support?




I don't think that plane for plane and mouth for mouth that it's really any different (BU or BD at 50 degrees). If you're using a thin single iron, I guess there is some chance that the plane iron bedded at 12 degrees is stronger because it's like pushing a broomstick at 12 degrees rather than putting a force at the end of it while holding it at 45 degrees to that force.

But, it's a personal preference thing if the other aspects of the plane are the same. Some folks like the BU planes (iron and no cap iron, moveable mouth, in the new ones there are setscrews etc, different adjuster) and some like the BD better (easier to camber and keep cambered, thinner iron, different adjuster, cap iron).

Hi Dave

This is largely my view as well.

If we subscribe to the theory that a plane is a jig holding a blade, whether that cutting angle comes from the bed or from the bevel should not - in theory - make a difference. However BU and BD planes are not equivalent when pushed - in the same way that the same dovetail saw will be experienced differently by a group of users. The hang angle of the saw, the way the teeth are lifted or dropped .. all these factors interact differently for each person. The BU and BD planes interact differently as well. I have attempted to describe this before in terms of force vectors, as in "centre of effort". Consequently, 50 degrees on a BU (38 degree bevel and 12 degree bed) and a BD (with a 50 bed and single iron) are different in the way they feel and cut.

Regards from Perth

Derek

[Kees Heiden]

I still don't see an elegant explanation for the difference you feel in bevel ups versus bevel downs. other then the difference in handle design. BTW, mr. Paul Sellers has the opposite experience from you, when using a bevel up plane. He prefers the bevel downs, thinks they are easier to push. His blog about this aspect is frankly said, quite incomprehensible, and he isn't prooving anything, but the overal message is clear, he FEELS that the bevel down planes cut easier. Funny when you watch the video and look at the effort when he pushes the plane, it seems that he gets the thickest shaving with the least amount of effort when using the old beech plane. http://paulsellers.com/2014/04/ups-and-downs-with-plane-irons-a-working-video-perspective/

I am sure that the newly produced bevel up planes are fine tools, easy to use and perfectly made. At the same time, I get excellent results with my modest collection of old Stanleys (most made postwar in the UK, so not even from the golden days). I am still struggling a bit with my wooden planes, but when they are finally set up well, they perform excellently too. Learning to use how to use the capiron was a major breakthrough in plane usage for me. It completely killed all my interest in new planes, they are just not neccessary for me.

We should never forget that the most intricate furniture, with highly figured kinds of tropical woods, was made with simple beech planes in the 17th - 19th century. Smack in the middle of that period, the chipbreaker was invented and it blew the single iron planes off the market. The metal bevel up plane design is much older but never gained much commercial succes. Later, when the Stanleys and the Britisch infills were introduced, they decided to use the same double iron design. For the woodworkers from these days it seemed to be obvious that this was the superiour design. They weren't rich, and their livelyhood depended on their tools. Quite a difference from us hobbyists.

[Derek Cohen]

I believe the action occurs in the first few fractions of an inch from the cutting edge. The cap iron/lever cap on a bevel up plane is too far away. Instead, the action occurs on the bevel. This is why some people keep multiple (cutting) irons for their favorite bevel up planes, each ground to a different angle. This creates an effect similar to that of setting the chipbreaker at different distances from the cutting edge on a bevel down plane. My 2.0467 cents, adjusted for inflation.

I believe that it comes down to how we view the effect is of the chipbreaker on the shaving. As far as I am concerned it is not magic. The laws of physics must apply. Newton's first and third law (if one really wants to be specific* :) ) would explain the chipbreaker bending the shaving at a higher angle while forcing the wood down at the same time, and that this limits the length of the split in the wood (i.e. changing of Type I to Type III - or similar - chips). Then the higher the angle the shaving is bent the shorter the length of the split and the more tearout is minimised. If this is indeed the case, then the conditions that cause the shaving to bend become central. There appears to be two factors involved: the angle of the leading edge of the chipbreaker, and how close this is to the edge of the blade. Closer and shallower versus further and steeper. Both can get you there. Different wood conditions require different setups.

The situation with a high angle BU plane is, I believe, similar: the conversion of the type I shaving to a type III (see Steve Elliott: http://planetuning.infillplane.com/html/shaving_formation.html).

Regards from Perth

Derek (partly tongue in cheek)


* First Law: re changes caused by an external force (the chipbreaker changing the direction of the shaving)

Third Law: for every action there is an equal and opposite reaction (the forcing down of the wood surface as the shaving is bent)

[Warren Mickley]

There are two actions going on in a double iron plane. One is cutting the wood and the other has to do with bending the shaving. The double iron plane cuts the wood at a relatively low angle, but the high angle plane (or a bevel up with a high angle bevel) cuts at a higher scraping angle. That is why the double iron cuts cleaner.That is why the double iron cuts with less effort. That is why the double iron leaves a finer surface. The double iron plane is much more sophisticated.

If you have not learned use the double iron to get a fine surface there is no shame. But please don't tell us that it will not give the best results.

[Pat Barry]

Pat,
Before you dot another i or cross another t, Bob Cratchet, ... BU
LOL

I actually just received big brother to the tool you referenced -- thanks by the way for your previous input into my decision to purchase it. :)

Now Winton, what angle do you recommend for the bevel on these fine tools?

and

do you think you might choose a different bevel angle in order to work with either harder or softer woods?

and finally,

do you grind your bevel on a grinding wheel as others have advocated or do you do work only with stones / flat grinding?

[David Weaver]

If we subscribe to the theory that a plane is a jig holding a blade



I agree that they are fundamentally different, if for no other reason, just in feel. I don't ascribe to the theory that the plane is just a jig, I think it's an oversimplification or an implication that the iron is the central focus and the rest of the stuff is of little importance. The elements of design in the rest of a plane are just important - I'd much rather have a properly designed plane with a mediocre iron than a mediocre (or worse) plane with a fabulous iron.

I don't know...that saying irks me, because it's usually repeated by beginners who don't know how important the location of the handle in reference to the blade is, or the location of the cutting iron to the length of the plane, etc.

To me, the BU planes feel more like a go kart or roller creeper, and the vintage BD planes feel more like a bicycle.