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View Full Version : Bevel angle on #4 - and other dumb q's



Prashun Patel
08-27-2009, 8:38 AM
I'm new (1 year) to the world of planes. I've been using a Stanley Bailey #4 and have been having trouble with tearout.

The bevel angle is 25 degrees. What's the normal? I've heard 38.

Also, I'm thinking to add a low angle jack plane as my next purchase. Would this kind of plane have more or less tendency to tear out on figured wood than a #4 sharpened to say 38 degrees?

John Keeton
08-27-2009, 9:42 AM
Shawn, I am just a little further into this than you. But, I had similar questions. The bevel down planes, such as the Stanley #4, are all ground at 25*, but the effective cutting angle (the angle of attack on the wood) is established by the frog angle, not the grind on the back of the blade/iron. So, if the frog is at 45*, then that is the angle of attack, regardless of the grind on the blade.

Conversly, with the BU planes, the grind on the face of the blade, in conjunction with the bed angle, establishes the angle of cut/attack, and is therefore adjustable. The bed on those planes is 12* normally.

I LOVE my BU planes, and have all three of the Veritas BU planes, with all angles of the blades. The BU smoother is an absolutely wonderful plane, and with the 50* blade, will tackle just about anything it is put on. If I could have only one, however, it would be the jack as it is "middle ground."

Now, we can let those with much greater experience chime in.

Sean Hughto
08-27-2009, 9:46 AM
Some woods tearout no matter what you do. That's when you turn to toothed blades, scrapers, and <gasp> sandpaper.

Are you sure your 4 is really sharp? Because sharpness and light cuts, along with angles of attack will go a long way to combatting tearout. A degree or two of bevel angle doesn't seem to be any sort of magic bullet (at least on bevel down planes). A HAF, on the other hand, helps sometimes.

Danny Burns
08-27-2009, 10:01 AM
-Make sure that the blade is very sharp.

-Take a very thin chip. Thin chips are weak, and break before pulling up the grain.

-If you tighten up the mouth on your plane then this might help. This puts downward pressure on the wood just before the cut zone. You only need to have a tight mouth ona plane when grain is giving you problems, otherwise one mouth setting for all thicknesses of chips in regular wood.

-You can wet the grain. This weakens the chip.

-Try coming across the grain a little, by skewing you plane to run in the direction of the flames. This reduces the lift that long continuos fibres produce by shortening the fiber length.

-Place the chipbreaker closer to the blade. This induces a break in the chip, and reduces lifting power that causes tear-out.

-You can try a very small 'back bevel' on the blade to increase the angle of attack from the 'built in' 45 degrees to say 50 or 55 degrees.
This would then amount to a 5 or 10 degree back bevel that is only in the area of 1/64 th of an inch or so, since the back bevel need only be thicker than the chip to do it's job. This increases the angle of attack, just like having a high angle frog would.

-If all this fails, then turning your blade upside down will turn your plane into a scraper plane. So a 45 degree bed and a 25 degree blade will give you a scraper plane at 70 degrees, and a 35 degree blade will give you 80 degrees.
Using a 35 degree bevel on A2 blades seems to help the edge last longer, and this still leaves you with 10 degrees of clearance between the blade and the wood surface, since 45 minus 35 equals 10, and only a few degrees of clearance is needed.
Then there is hand scrapers and toothed blades, but that is way down the list.

I think it was Derek Cohen who posted recently about flipping the blade to get a scraper action, in a post on scraper inserts. So a check here might be helpful.
Found it.
Last post at the bottom.

http://forum.canadianwoodworking.com/showthread.php?t=14822



Then IF all these fail, you can take the plunge of buying a new toy! Or you can just use the tear-out as a convenient excuse to buy a nice new plane! LOL

John Keeton
08-27-2009, 10:24 AM
Or you can just use the tear-out as a convenient excuse to buy a nice new plane! LOLThat is usually the only motivation I need - or less :D

Prashun Patel
08-27-2009, 10:42 AM
Thanks for those wonderful responses.

I'm using a Worksharp, and am pretty sure I'm 'reasonably' sharp. I get wonderful results on some woods, but I have a piece of cherry that has a sharp curl at the end that keeps sniping on me.

My #4 has a (don't laugh) fixed mouth; not adjustable.

I am also learning how to take paperthin shavings. I almost always run at a skew angle too. My chipbreaker is 1/16"ish inch from the tip of the blade.

I'll try resharpening my blade.

John Keeton
08-27-2009, 10:57 AM
Shawn, you can adjust the "mouth" by moving the frog forward. That will close up the mouth opening. Personally, for thin shavings, I might try closing up the chipbreaker just a little - others may feel differently. For me, sometimes just a very slight movement of the chipbreaker can make a difference, although 1/16 is close. I have also found that polishing the face of the chipbreaker can help.

But, having said all of that (from a guy with very little experience on this topic!) - I still love my BUS!!

Eddie Darby
08-27-2009, 11:01 AM
...but I have a piece of cherry that has a sharp curl at the end that keeps sniping on me.
Snipe is from machinery biting off extra. Tear-out is the term.


My #4 has a (don't laugh) fixed mouth; not adjustable.
The mouth does not adjust on Bailey's but the frog can be snugged up to the mouth to close things up.

If all these fail, try the back bevel approach, which is a very small bevel on the backside, which is to say the flat-side of the blade, which is the face opposite to the beveled side of the blade.

If you find yourself needing to do this 'back bevel' a lot then a spare blade set-up with a 10 degree or so 'back bevel' might come in handy.

Sean Hughto
08-27-2009, 11:21 AM
FWIW, skewing the plane effectively lowers the cutting angle. It also sort of widens the mouth as the diagonal between each point on the blade where cutting is occuring and the front of the mouth is longer than the straight perpendicular line.

Reversing grain in cherry can be a real serious challenge. Cherry varies greatly from piece to piece and can seem a dream or a nightmare.

I've never used a Worksharp, but "reasonably sharp" is not gonna cut it (so to speak) on challenging grains.

Prashun Patel
08-27-2009, 11:49 AM
"reasonably sharp" is me being humble. I think the blade may have dulled. I know how to sharpen it well and properly, but have seen enough videos to know my technique can always improve...

Sam Takeuchi
08-27-2009, 1:44 PM
If all fails, add back bevel. You don't need much, you can try 5 degree back bevel and see if it works. If it doesn't, try 10 degrees. For the most part, 55 should work. You can jump to 60 (or commonly used 62) degrees, but probably unnecessary to go that high except on the most demanding and interlocking grain.

Or if you are comfortable a card scraper, you can scrape. But I think back bevel should do fine. Just don't make back bevel too big. It just needs to be a hair wide.

Bill White
08-29-2009, 12:53 PM
Close the chipbreaker to less than a 1/16th. Don't take too rank a cut. Just like you would not/should not hog a power planer (gasp-the dreaded word), don't do it with a hand plane either. Love my #4.
Bill

philip marcou
08-30-2009, 4:57 AM
Thanks for those wonderful responses.

I'm using a Worksharp, and am pretty sure I'm 'reasonably' sharp. I get wonderful results on some woods, but I have a piece of cherry that has a sharp curl at the end that keeps sniping on me.

My #4 has a (don't laugh) fixed mouth; not adjustable.

I am also learning how to take paperthin shavings. I almost always run at a skew angle too. My chipbreaker is 1/16"ish inch from the tip of the blade.

I'll try resharpening my blade.
Shawn,
A #4 bevel down smoother is not the best one to use if you are dealing with difficult grain and Danny has come up with a lot of relevant information for you to consider-but I would caution against doing back bevels to increase the cutting angle on a light plane such as a #4 especially if it is a Stanley type or clone, and say that this modification works better on the heavier wider #4.1/2 or #5.1/2. The #4 is a general purpose smoother for light work in my view, unless you are doing small work -in which case it still fails with difficult timbers since its standard cutting angle is 45°.
Ofcourse I am assuming that your blade is well honed and the plane is properly set up for taking fine shavings, but the chip breaker could come closer than 1/16th" -almost as close as you can get it....
I suggest you look at acquiring a better smoother . It needs to be heavier, can be either bevel down or bevel up but if bevel down then a York pitch is preferable-and I think the Lie Nielsen provides a model on which you have a high angle frog option. Bevel up planes would give you more options and versatility as it is easy to hone and or grind the blade(s) at various angles to alter the cutting angle.

Eddie Darby
08-30-2009, 8:08 PM
Shawn,
A #4 bevel down smoother is not the best one to use if you are dealing with difficult grain and Danny has come up with a lot of relevant information for you to consider-but I would caution against doing back bevels to increase the cutting angle on a light plane such as a #4 especially if it is a Stanley type or clone, and say that this modification works better on the heavier wider #4.1/2 or #5.1/2. The #4 is a general purpose smoother for light work in my view, unless you are doing small work -in which case it still fails with difficult timbers since its standard cutting angle is 45°.
Ofcourse I am assuming that your blade is well honed and the plane is properly set up for taking fine shavings, but the chip breaker could come closer than 1/16th" -almost as close as you can get it....
I suggest you look at acquiring a better smoother . It needs to be heavier, can be either bevel down or bevel up but if bevel down then a York pitch is preferable-and I think the Lie Nielsen provides a model on which you have a high angle frog option. Bevel up planes would give you more options and versatility as it is easy to hone and or grind the blade(s) at various angles to alter the cutting angle.

I see that at the Lie-Nielsen site he only offers a 50* frog for thenarrow #4 plane and #5 plane, while he offers a 50* and 55* frog for the wider #4 1/2 plane.
So perhaps the #4 & #5 had a test trial with a 55* frog, and did not do so well.

http://www.lie-nielsen.com/catalog.php?grp=1246

Would a 5* back bevel be acceptable for a #4?

philip marcou
08-31-2009, 2:37 AM
"Would a 5* back bevel be acceptable for a #4?"
Yes, but I maintain that the #4 is not a good candidate for the treatment and a wider heavier plane would benefit more from the use of a back bevel. I just think that the #4 size is a general purpose plane for light work and should be left "standard".

Prashun Patel
09-06-2009, 10:03 PM
I found out the problem with my Bailey #4 (don't laugh):

THE CAP SCREW ON THE LEVER CAP WASN'T TIGHT ENOUGH!

How dumb is THAT?! I always kept the cap screw just tight enough to allow the lever to engage without too much effort. However, I believe this was not holding the blade firmly enough. When I tightened it more - I didn't overdo it - it started taking even long shavings with minimal effort.

Sean Hughto
09-06-2009, 11:36 PM
Things like that happen to me all the time. A plane doesn't work, and it ends up being somthing simple that I've failed to notive. The delay in figuing it out just gets shorter and shorter, cause you more quickly realize it's you and not the plane!