I think i haven't understood nothing..

[GEPPETTO]

Hi all,
I read a lot about bevel angle of chisels and plane irons. I thought I had understood that angle must be the same in chisels and plane irons (25° with a microbevel of 30°).
Well, last evening reading the "The Complete Guide to Sharpening"
by Leonard Lee I seen that Lee says that with the plane irons the bevel angle must be almost 30° for to avoid the chattering of the blade.
I am a little in confusion.

At which angle you grind your plane iron?

 

[J.A.S]

Geppetto,

I'm only a novice myself, but, for what it's worth, I sharpen my plane blades as you do: 25 degrees for the primary bevel and 30 degrees for the secondary, although I do use an initial grind of 23 degrees.

I haven't read Lee's book, but I doubt that he advises that the bevel should be ground at 30 degrees: it's more likely that he suggests that the total sharpening angle should be 30 degrees: grind + secondary bevel = 30. I suspect those are the angles that most people use.

I certainly wouldn't normally go any higher than 30 degrees for a low-angle block plane: that would cancel out the benefits of the low angle bed.
However, with low angle bench planes, like the Veritas low angle jack, and the Lie-Nielsen 62, (and the Stanley 62 if you can ever find one), having a second blade sharpened with a higher angle makes sense. That way, the plane can also be used as a 'normal' bench plane, particularly for difficult timbers.

Having said all this, I know that David Charlesworth recommends a higher angle in normal bench planes. This might be because of the types of timber that he frequently encounters: hardwoods with difficult grains. Yet, if I recall correctly, he advises against sharpening a bench plane any higher than 35 degrees, and, indeed, begins with a grind of 23 degrees.

Above all, I think, if you're getting good results with the method you have been using, stick with it. But, if you want to try something different, try it: if it works, great. If it doesn't, you've learnt something.

Anyway, I'm sure that Alf will be along soon, and she'll be able to advise you better than I can. I now await being shot down in flames by her for my ignorance...


Good luck.
Jeremy

 

[Alf]

Anyway, I'm sure that Alf will be along soon, and she'll be able to advise you better than I can. I now await being shot down in flames by her for my ignorance...

Au contraire, you've saved me a heap of typing. All I'll add is that I believe DC may use a higher total angle because it works better with the A2 irons he uses. Somewhereorother I read its edge tends to last better at a steeper angle, IIRC. BB'll know if I'm talking rot, but he doesn't venture into the darkness over here, so if some nice Mod would move this into Hand Tools...?

Cheers, Alf

 

[Frank D.]

Hi everyone,
For bevel-down planes (bench planes) on North American hardwoods (maple, birch, walnut, beech, oak) the standard seems to be 30° with a microbevel around 33°. The rule as I know it is to get the lowest bevel angle possible without the edge breaking down. I do all my bench-plane blades this way (30, 33°) and it seems to work fine for softwoods too. The 25° standard that many companies provide here is meant for carpentry or softwoods only. It's also easier for users to increase bevel angle to their liking than to lower it.
For bevel-up planes it really depends on what you want to do, the total (effective) planing angle rules. For end grain, 25° usually works for me, but I sometimes go up to 30° for tough woods. FOr long grain planing I sharpen at around 35°. This does not totally eliminate the advantage of low-angle bedding, because the blade is supported differently. For figured woods I can go up to a 45° angle with a microbevel around 47°.
HTH,
Frank D.

 

[Chris Knight]

Gepetto,

Everything has been said really but I would just add this.:-

Experiment!

If a particular angle doesn't work well for you try another. There is no hard and fast rule - just accumulated experience. The angle that leaves a nice surface and doesn't need sharpening every five minutes is the right one.

And, since no-one has mentioned it in this thread, I will say :-

Wax your sole!

The resistance to planing comes from two sources - the wood being cut by the blade and the friction of the sole on the wood. The latter often uses two thirds of the effort you apply so do yourself a favour and apply some wax to the sole of your plane. Any wax apart from a wax containing silicone will do. (Silcone messes up the subsequent application of finishes to the wood)

 

[Midnight]

Geppetto

just to confuse things..

I've stuck to honing the secondry bevel on all my planes (except the #112 for obvious reasons) at 30 degrees... never seen any reason to change so far, and the stuff I work isn't exactly balsa wood ... oak, beech, figured elm... no bother..

Chris has a point about waxing the sole... prob I've found with that is.. it never lasts more than a dozen strokes or so..

 

[Anonymous]

ok, my tuppence worth, which may be so much rubbish, but anyway:

bevel up planes - the angle of attack of the plane iron is determined by adding the frog angle and the bevel angle - so, take an LN low-angle, 12 degree frog. A 30 degree bevel gives 42 degree angle of attack, only slightly lower than a regular bevel up. Higher iron bevel angles allow you to approach York pitch (50 degree) angles, useful for highly figured grain, or wood that's prone to tear out.

bevel down planes - the angle of attack is governed purely by the frog angle - 45 degree standard, 50 degree with York pitch. In this configuration, the lower the bevel angle you have the better, from the view point of sharpness. However, very low bevel angles are more fragile, and prone to blunting, breaking and chipping. So, compromise angles are needed, to achieve the best sharpness versus edge longevity. Added to these factors for bevel down irons is the clearance behind the 'pointy' bit of the iron. Obviously, with a 45 degree frog, if you had a 45 degree bevel then the whole of the bevel would be parallel, and rubbing on, the stock - the lower the angle, the more clearance behind the business end. I don't think that aspect actually is a huge consideration on bevel angles though - just don't go for a grind greater than 45 degrees! :lol:

ok, now i'm ready to sit back and be shot down in flames

 

[GEPPETTO]

Hi, thanks for the answers.

Yesterday I have honed my plane blade with a bevel of 25° and a microbevel of 30°. I am trying to do that by hand without any jig how Maurice Fraser says herehttp://www.antiquetools.org/sharp/index.html.

However, after the blade was sharpened like a razor because I shaved all my hand hairs I tried to plane a board of black locust. First, all OK. But after the flattening is become too hard.
I seen and felt with the finger that the back had a "burr" . :shock:

Then I rethought on my planning system and I have understood that I rub the wood with the sole with the back movement too ( I do not raise the plane at the end of the stroke, for the most of the times).
I think that it is the same like stropping the blade and therefore it is easy that burr is formed. Is it true??

 

[Chris Knight]

Gepetto,

It is indeed not good practice to slide your plane back as this does needlessly wear the blade. Better is to lift it as you say. However, I suspect a more likely cause of the burr you feel is that your edge is just too fragile. Try a steeper angle (secondary bevel) at say 35 degrees.