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James Phillips
09-26-2010, 10:33 PM
What angle does everyone grind their bevel down planes? Right now I am grinding mine at 25 deg, however I am thinking about changing to 30 with a 33-35 micro bevel. Since the angle seen by the wood is really the frog angle is should not affect how it cuts, or am I horribly mistaken?

I am work with power and hand tools, but am really getting into my handtools lately

Thanks

David Weaver
09-26-2010, 11:00 PM
If you want to add a microbevel, you're better off doing it with a 25 degree primary. The microbevel can move the length of the iron a lot easier.

If you want steeper because you're not happy with the edge retention, then you could also grind a primary at 30 degrees (assuming you're honing the hollow grind, and assuming that you're grinding a hollow).

The clearance angle (what's left after you subtract the frog angle, as you call it, from the last bevel on the plane) should be at least 10. More is better, but not necessary.

Larry williams has mentioned on here before that with more clearance angle, the iron behaves more similarly in a variety of woods (that's not exactly what he said, but that's what I gathered from it). If you use 10 degrees, you'll notice the depth of cut may not be the same on a plane from maple to pine and back. It will, however, cut either one fine as long as it's sharp.

Honing and what you do is something where there's no "right" answer. If it's working and you're getting the surface you want and edge retention you want, and it's not onerous to do, then it's right enough.

Andrew Gibson
09-27-2010, 12:31 AM
I do exactly what you are thinking. I use a primary bevel of 30* and then add about 2* of micro bevel. I think it is beneficial, especially now that I am acquiring a2 irons for my bench planes.

My understanding is that A2 likes to be sharpened at 30* or better, so I simply have always sharpened my a2 irons to 30+2*.
I just aquired a 60-1/2 block plane and ordered a new iron for it from lee valley, I opted for o1 in hopes of better performance when ground at 25*

George Beck
09-27-2010, 6:46 AM
Well I use several angles. One of the nifty things about bevel up planes is the presentation angle can be easily changed. I keep several blades for my LV low angle jack plane. One at 25 degrees which I use for softer woods and end grain. One I put a micro-bevel of 5 degrees (30 degree presentation) and one I use a secondary bevel of 39 degrees for very hard or highly figured woods. Because the plane is bedded at 12 degrees I am presenting the blade to the wood at roughly 37 degrees, 42 degrees and 49 degrees. I recently was working with some figured maple, where I started with a toothed plane, switched to a 49 degree presentation and finished with a scraper blade. All with the same plane. This makes these BU planes really great as a starter plane when one doesn't have multiple planes for multiple applications. I have not found a significant difference between A-2 and O-1 steel so far as edge retention goes. I do find the high carbon steel a bit quicker to sharpen.

George Beck
09-27-2010, 6:48 AM
Opps one correction. I use LN that is Lie-Nielsen planes.

Terry Beadle
09-27-2010, 10:45 AM
Bevel down planes are usually set with a 25 degree primary. A 2 ~ 4 degree micro bevel is useful to give more edge retention.

Bevel up planes usually are in the 30 degree primary due to the frog bed angle being considered low angle. However, some bevel up planes have higher bed angles for bevel up smoothers.

The primary consideration is "What are you going to use the plane on and for"?

If you are doing a shooting operation, you usually want a lower angle, especially for end grain.

For common planing activity a 45 degree bed is considered standard. The bevel is only increased from 25 degrees if the steel or material you are working on causes the cutting edge to deform too quickly.

If you are planing hickory or rock maple, you probably want a 30 degree down bevel and then a micro bevel. The higher the bevel angle the stronger the cutting edge but the more force it takes to slice through the wood.

If it's not the wood that's causing edge problems but is due to poor steel, then replacing the blade with a O1 or A2 Hock blade is recommended. LV, LN, Galoot, and Hock blades are not cheap but they are worth it. Again, I'd set the down bevel angle higher, even to beyond 40 degrees before I'd just say the steel is poor and needed to be abandoned. Even cheap Stanley stock blades will do if you keep them sharp.

If you are planing some soft pine, basswood or cedar, then a 25 degree down bevel will be ideal and no micro bevel required. However, most folks put a micro bevel on the bevel due to ease of sharpening time.

So if you are working in hard woods most of the time, and you have a Stanley 4, 5, or 6 then a 30 degree down bevel is probably a good idea. If you are planing soft pine, SYP, cedar, or other softer woods, then a 25 degree down bevel is going to allow easier planing.

All the above being said, David Charlesworth has a technique of setting up a plane to take just very lite shavings with a plane blade set up with a slight curve. I recommend you look into his planing DVD's as they are a great resource and will improve your projects IMO. His chisel DVD's are also really good.

Happy shavings !

Jim Koepke
09-27-2010, 1:34 PM
For a bevel down plane, as long as you have enough of a clearance angle behind the edge, your personal experience will be the best judge of what angle to use.

My blades are mostly at 25° to 30°. I do not use micro bevels or back bevels. For me it works fine like this. Your milage will most likely be different.

At 25° blades will chatter a bit more in some situations. Mostly, this is noticed with my #113 circle plane. It also has to do with how well the blade is supported and the thickness of the shavings.

Something that is more important than the angle is the sharpness.

jtk

Derek Cohen
09-28-2010, 2:16 AM
What angle does everyone grind their bevel down planes? Right now I am grinding mine at 25 deg, however I am thinking about changing to 30 with a 33-35 micro bevel. Since the angle seen by the wood is really the frog angle is should not affect how it cuts, or am I horribly mistaken?

I am work with power and hand tools, but am really getting into my handtools lately

Thanks

Hi James

If you plan to add a higher secondary bevel, there is no need to alter the angle of the primary bevel. The wood only sees the secondary bevel. You will not achieve any more edge durability with a 30 degree primary bevel over a 25 degree primary bevel.

The angle of the secondary bevel is always a compromise - a compromise between edge retention (on hard wearing woods) and sharpness (the more acute the bevel angle, the greater penetration is has = sharper effect). So it will come down to the type of wood you plan to plane. For most softer woods I would leave the secondary angle at 30 degrees and lower. As David pointed out, too little clearance will also affect performance negatively.

You have not stated what steel/blade make you are using. Softer steel may not hold up as well at lower angles. Frankly, however, if the steel is not holding up at 25 degrees on a BD plane you should look into a better blade.

Regards from Perth

Derek

David Weaver
09-28-2010, 8:01 AM
As David pointed out, too little clearance will also affect performance negatively.


I had never thought of clearance around 10 degrees being "not enough" for some things until Larry mentioned that. I'd noticed, I guess, that I had to change the depth going from pine to hard maple, because the maple cut was drastic right from pine (I guess due to less springback). So noticed, but never really thought too hard about it, just always made the adjustment and went about my business.

"not enough" is sort of misused, too, I guess. The plane still works fine, just the depth of cut in a variety of woods is less consistent.

I still like a bench plane with 35 degrees secondary or tertiary bevel, though, the iron lasts a very long time - much less likely to chip out and it still leaves a nice surface when the iron is in the no-chipout condition. I just know more about why it's behaving the way it's behaving now.

Derek Cohen
09-28-2010, 8:29 AM
Hi David

Keep in mind that the figure given to "sufficient" clearance is 7 degrees, as suggested by Leonard Lee.

http://books.google.com.au/books?id=CtkWaJw5iXkC&pg=PA16&lpg=PA16&dq=leonard+lee+clearance+angle+bevel+down&source=bl&ots=TzqHSKJ6TJ&sig=YGuCg2ifNO1oRmcuH4e-pCHQMJM&hl=en&ei=lt2hTMf3OIW2vQOfs7naAw&sa=X&oi=book_result&ct=result&resnum=3&ved=0CCEQ6AEwAg#v=onepage&q&f=false

Regards from Perth

Derek

David Weaver
09-28-2010, 8:42 AM
Derek, yes, I've seen that. I guess the discussion was fairly complicated. Is 10 degrees enough to get a good surface? Certainly. 7, of course, or it wouldn't be in Leonard Lee's book.

Larry's commentary was the first time I've seen anyone advocate 20 degrees as a preferable amount, but I understand where he's coming from and enjoyed the topic because it's the first time I've seen something plane-related that wasn't an all-out bash on what the best sharpening method is (though I have been guilty of participating in those, mostly because i'm a sharpening stone pig).

I don't have anything below 10 degrees at this point, but I have a lot of planes in that general ballpark, including a gaggle of japanese planes. I work hardwoods more than softwoods, though, and when i do work softwoods, they're usually just drawer sides or part of a carcase that doesn't show, so I don't get too concerned about them, at least not in the same sense as running back to the stones at the first sign of a line-creating smooth-surface-ruining chipout on a smoothing iron.