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Michael Peet
05-11-2010, 8:53 AM
I am getting near the joinery part of my bench build. I am planning to drawbore all the M&T joints ala Chris Schwarz. In making a couple practice joints, I notice there are sometimes small gaps between the sides of the peg and the edge of the hole. I was wondering if I can get away with using a drill that is 1/64" smaller than the nominal peg size. I tried one that way and it was a lot tighter, but I am afraid of splitting the work. Is this asking for trouble? The bench material is ash.

Also, I understand oak is commonly used as peg material for its toughness; are there other darker woods that could also work? Like rosewood or similar.

Mike

Paul Davis
05-11-2010, 9:46 AM
When I drawbored my workbench and saw those same little crescents around the pegs (caused by the leverage on the peg as it passes through the offset in the tenon), I concealed it by driving the peg past flush in the leg, then capping with an oversize short piece of peg. It can still be extracted in the same way as a normal drawbored peg (either drilled out or driven through), and doesn't reduce the length of the peg much. I think I used a 1/8 or 3/16 length peg for the caps, on top of a 4" peg. I didn't use any glue on the tenons, mortises, drawbore pegs, or caps. I think you could glue the caps (just a little drop would do) without worry about making the joint difficult to take apart, if they weren't staying in.

I considered it the height of OCD--in other words, just a regular day in my shop.

PS If you want a contrasting material for the pegs, you could make the caps only out of it. Use tough, cheap oak for the pegs, and expensive rosewood in very small quantities to finish it off.

Derek Cohen
05-11-2010, 10:18 AM
Hi Michael

You realise that the crescents are created by the wood bending inside the joint. I do not think that a smaller hole will prevent this - instead you may just snap the pin as it will not go in.

Rather drill the offset hole just a smidge away from the outer hole (i.e. less than you would otherwise have done), then the pin will not have to bend as much, and will not crescent out as much.

Regards from Perth

Derek

Johnny Kleso
05-11-2010, 10:30 AM
Trick I use on badly dented planes is to wipe the wood with a damp rag and then hold a iron over the wood and dents swell out to original shape..

You may have to do this two or three times depending on how wet your rag is..

Josh Bowman
05-11-2010, 6:53 PM
I really like draw boring. It does a great job. The first and only time I used it was on my bench. The stretchers to the legs went great. The huge legs to top tenons was disappointing. Only about 1/2 of the pegs got all the way through the tenon into the other side of the mortise. The 3/8" x 6" pegs broke as they met the other side. I still feel the joints are OK, after all it's a mortise and tenon and I just put clamps on them, but I lost some of the "cool" factor of just driving the pegs home. I said all that to say this. The little crescent gaps may be the least of your problems. Now having said that, the now planed off pegs look great and contrast nicely. The result of saw dust, fraying etc. has hidden any of the gaps.

Jeff Johnson
05-11-2010, 6:57 PM
You could consider drilling the hole the same size as the peg and compressing the wood of the peg by rubbing it hard with a smooth metal rod. Either leaving the last bit of the dowel uncompressed or re-expanding it with a spritz of water would probably prevent the half-moon in the hole.

Michael Peet
05-11-2010, 7:15 PM
Thanks guys. Given your input I think I will not try to go a size smaller on the holes.

Mike