Choping out waste for dovetails

[Michael Gabbay]

I'm having a problem when I chop out the waste for my dovetails. I'm currently working on 6 drawers for a vanity. The drawers are poplar with through DTs.

I've been using a coping saw to remove the bulk of the waste, leaving about 1/16". I strike the base line with a chisel on both sides and then begin to chop away the waste starting about 1/32nd (halfway) from the baseline.

I've tried using Ian Kirby's method of angling the chisel to remove less in the middle and just keep chipping away. I've also tried keeping the chisel at 90 degrees.

Either way I'm getting tear out (divots) in the middle of the piece. I'm using 3/8" or 1/2" freshly sharpened chisels.

Any suggestions???? :confused:

Thanks, Mike

[Steve Wargo]

Not trying to be hard on you but there is a difference between sharp and SHARP. In poplar you should be able to pare 1/32" off without a mallet if your chisels are really sharp. Hope this helps.

[Michael Gabbay]

Steve I'm ok with the comments... :)

From a sharpening stand point I've reground my Marples to 25 degrees and flattened the backs using Norton 1000 and 8000 stones. The primary bevels are sharpened using the 1000 and 800 stones and the secondary bevels are 2 degrees. They are also sharpened with the same stones. I've been following Charlesworth's method for sharpening and removing the wire edge etc.

I know just saying that I'm sharpening using an 8000 stones means squat since you can't see how I'm doing it etc.

I'll resharpen them again to see if it helps.

Thanks, Mike

[Mark Singer]

Harder wood will yeild cleaner cuts....maple or walnut are very good

[Dan Forman]

Not really a problem, as they won't show, and don't present a reliable glue surface anyway. As Mark said, poplar, pine, and other softer woods will have more of a tendecy to do that than harder woods.

Dan

[Michael Gabbay]

Thanks guys for the responses.

I've always had better success with cherry and walnut. But since these are drawers I'm using poplar.

Mike

[Mike Wenzloff]

Hi Michael, as others have mentioned, Poplar is a soft hardwood and tears badly anyway due to fiber compression even with sharp tools.

That said, you will find after you hone again that you should be able to pare that away faster and more cleanly than choping. Also, After every joint or two, I usually hone my tools a couple swipes on my 2000 grit stone as I work. Keeps the edge fresh.

Mike

[Dennis McDonaugh]

Michael, I use a 20 degree bevel on a sharp paring chisel on poplar and get considerably better results than with a normal 25 degree angle.

[Michael Gabbay]

Dennis - I think I'll try honing an older chisel to 20 degrees and try that.

Mike - I'll sharpen more often. I usually do it after each drawer or two.

I was reading the Charlesworth article in FWW again last night and he recommends a hollow bevel on the grinder. Does anyone do that? Does it make much difference?

Mike

[Steve Schoene]

The hollow bevel from the grinder makes it a lot easier to sharpen a blade free hand since there is less tendancy to rock the blade and since less material has to be removed to create a fresh edge.

Something that I think is important is often missing from sharpening discussions, and that is the use of a leather stop. I learned to use a bare piece of leather--no grit--as a final step after a hard arkansas stone. It makes a BIG difference and can be used a number of times before having to drag out the stones again.

[Peter Mc Mahon]

Hi Mike. First thing that I would say is to not worry about it. It is not seen and it has 0 glue strength anyways. Your problem arises from unsupported wood. When you are cutting in from each side you have wood backing your cut. This prevents the fibers from bending and then snapping off. When you reach the middle though, there is nothing to support the cut and the fibers bend and break off below the cut surface level. The best way that I have found to avoid this is to cut 90* in from both sides and when you reach the last center piece [the piece that gives you the tear out] angle your chisel in slightly for the last cuts from both sides. This way you are supporting the last fibers. Peter

[Bob Johnson2]

This thread answers a question I was going to raise on why I'm having so much tearout on poplar using a leigh setup. It's my first time using one of these and I expected better, leaving a fairly ragged cut. Time to mill some maple down and try again.

[Terry Beadle]

The sharpening techniques you are using work great. I find that some diamond paste or Tormek paste on a hard maple surface puts the last little bit of sharp to the blade. Tear out in a end grain dovetail is part sharpness and part material quality. I think you have the sharp part bagged. The poplar you are using should work best if you don't use a mallet but use just your push stroke but take the very thinest slice you can. Also, angle the cut from the top towards the half way mark of the middle towards to open. Then work your way back to the verticle line or if you don't object a very slight concavity towards the middle mark. If you want to use the mallet, get a very light one and give it very light little taps. This very lite tap technique works for me in pine. I have a Japanese 1/2inch paring chisel that I use for tough wood material like what you are dealing with. It cost $150 but what's a tax return for? Good luck with your DT's!

[Keith Christopher]

Harder wood will yeild cleaner cuts....maple or walnut are very good

Lyptus does this as well. I have to sharpen my chisels ALOT using this wood.

[Alden Miller]

Mike, you're still stressing about that?

If you don't hurry up I'm going to win!!!!

-Alden

[Michael Gabbay]

Alden you still have to install the built-ins...... :D Besides the tub is in!

Alden and I are having a little race. He's been working on a set of cherry built-ins for a customer for about a century (+/- 9 years). I've been working on a bathroom remodel for almost the same time.

[Alden Miller]

Your response shows you are nervous!

:D