Drilling and tapping hardwoods

Picture of Drilling and tapping hardwoods
Drilling and tapping hardwoods
There are several ways to attach threaded metal fasteners into wood fixtures. For example,  inserts and  t-nuts can be used to add  a threaded connection to a jig. But often I prefer to drill and tap threads directly into the wood fixture.  Many hardwoods can be drilled and tapped, however softwoods lack the necessary machinability and holding capacity. The best wood I have used for threading is Jatoba,  (Brazilian Cherry). Jatoba is very dense, hard, fine grained, and threads extremely well. Oak and Padauk are fine also. I find these threaded wood fixtures hold a bolt extremely well.
Hardwood is a forgiving material to drill and tap. Use a 5/16” drill bit for 3/8” threads, 7/32”  bit for 1/4 “.  I don’t thread anything less than 1/2”  thickness. Use a standard coarse tap to cut the screw threads. 
Making threaded woodworking jigs, clamps, furniture handles and knobs from exotic hardwoods adds a beautiful touch to projects.  Material is not cheap, but these parts are small so final cost is low.
Largrin1 year ago
Great ible. I been doing this for almost 40 years, Your advice is good!
Bill WW (author)  Largrin1 year ago
Thanks for the comment.

I had been using threaded inserts, but then realized direct drill and tap would be better and easier.
Ugifer1 year ago
Years ago I skip-raided some incredibly dense hardwood that may well be your Jatoba - it was being used to make fire-doors in a chemistry lab. It looks like the wood in your first picture. I've never known what it is, only that it blunts meal tools!

I have in the past screwed machine screws directly into holes drilled into it because it's so incredibly hard and dense. I think I can feel some hardwood nuts coming on!

Thanks for a useful instructable.
Bill WW (author)  Ugifer1 year ago
Thanks for looking.

Yes, Jatoba is a great, dense, fine grained hardwood. Sometimes called Brazilian Cherry. The lumber I have is heavier than water.

I am now submitting short concise Instructables, The long complicated ones are great, but most do not fit my particular equipment or situation.
rimar20001 year ago
I attest this is very useful, Bill. Often I do hardwood nuts, they serve in many occasions. Your tips are always good.