The Forestry Forum

Hi,

I would like to buy an auger bit to drill holes for mortises. I was thinking of drilling them by hand as it will be the first time I do mortise and tenon joinery and I do not want to go too fast. I was wondering about the drill bit size. Should I buy a bit 1/8" narrower than the mortise width? I will be working with Doug Fir. Should the Wood Owl Ultra Smooth tri-spur bits work fine to drill by hand?

Thanks!

Normally we use a bit that is the same width as the mortise. But some people do like to use a smaller bit.
That's up to you.

Jim Rogers

the bit should be the same as your tenon.  unless this is very wet and it will shrink.  I pre dry my leg stock for benches so the seat mortises can shrink and tighten around the tenons.  what are you building.  are you harvesting your own wood, or is this code for using 2 x 4 wood from the store?  those bits are good for a hand drill but may tend to oversize the hole a bit.  I use forstner bits in a drill press.  I have built a table that makes my radial drill press into a compound drill press to get leg angles consistent.  Are you hand making the tenons or do you have tenon cutters?  I started out the same as you.  I will find a link to making rustic benches and add it.  not sure if that is what you are doing, but rustic furniture is a common application.


 What up Benches? (http://forestryforum.com/board/index.php?topic=105007.msg1634016#msg1634016)

Quote from: doc henderson on September 18, 2019, 09:33:48 AM
the bit should be the same as your tenon.  unless this is very wet and it will shrink.  I pre dry my leg stock for benches so the seat mortises can shrink and tighten around the tenons.  what are you building.  are you harvesting your own wood, or is this code for using 2 x 4 wood from the store?  those bits are good for a hand drill but may tend to oversize the hole a bit.  I use forstner bits in a drill press.  I have built a table that makes my radial drill press into a compound drill press to get leg angles consistent.  Are you hand making the tenons or do you have tenon cutters?  I started out the same as you.  I will find a link to making rustic benches and add it.  not sure if that is what you are doing, but rustic furniture is a common application.


What up Benches? (http://forestryforum.com/board/index.php?topic=105007.msg1634016#msg1634016)

Thank you. It is for a 8'x16' chicken coop. 4x4 posts with 2x4 braces in dressed Doug Fir that I had to special order. 1" mortise&tenon width. I was going to cut the tenons using a Ryoba saw. I have 1", 1.5" and 2" framing chisels as well. So it looks like I should get a 1" bit?

good luck and sorry I went down the road familiar to me.  Jim Rogers is the authority.