Tapping wood thread question

[MikeMcCoy]

This is a new one for me and I just picked up a tap to make some attachments for the lathe. I'm drilling out the stock 1/8" smaller than the tap per the directions and using the lathe tail stock to keep tension on the tap while I turn it. I had a couple of cases using cherry where the threads seem adequate although they didn't appear distinct like I expected. I take it soft wood is a no go with these? I tried a couple of pieces of 2x4 and you couldn't even see any trace of threads but I wanted to make sure it wasn't my technique before I blew off a good source of scrap.

[leehljp]

Mike,

I am not quite clear on what you are trying to accomplish. (Sometimes after a time of Japanese thinking/speaking, somethings just don't make sense.)

Soft wood does not make good threads or hold as well, but it will work in some cases. Hard wood and close grained hardwood such as maple and cherry does much better.

Now - as to what I did not understand - are you threading for metal bolts or the threaded wood bolts/rods? It is not really necessary to thread wood for metal bolts except for sizes 1/4 in and larger. Metal bolts will make their own threads.

For threaded wood bolts/rods, hard wood is the only way to go. I don't see how it can be accomplished with softer woods as the threads will be cut in a "crushing" fashion, thereby weakening it.

[Ken Massingale]

Morning Mike,
Sounds like the Beall 1 by 8 spindle tap?
I just picked one up for making jam chucks, etc. for the lathe. I haven't used it yet, I'll try to make time today to see how it goes here.

[MikeMcCoy]

That's the one Ken and the same purpose. It worked fairly well on the cherry but like was said above, I sure wouldn't want to be on the business end of some soft wood coming off the lathe.

[ke4rdb]

Never used a wood tap that large but I do use a regular metal tap to tap screw threads for jigs and bottle stoppers. I've found that some woods when drilled with the right size drill seems to large....

Had this happen a couple of days ago w/redheart that I tapping for a bottle stopper. But had no issue w/rosewood. Had to go 1 drill size smaller and all was well with the redheard. I have also noticed that softwood just do not take threads well, they tend to tear.

Quess if I was you I would try different size holes in each wood I wanted to tap to see which one works the best for that type of wood.

James

[MikeMcCoy]

I haven't had time to play around much but for the first time in awhile, I followed directions and used the 7/8" bit for the 1" tap. I'll experiment with a little smaller size. Like said above, the cherry seems to hold alright but I'd feel a little more comfortable with better defined thread for my intended use.

[guycox]

Something else that hasn't been mentioned -- don't even try to thread end grain...

I've had great luck with red oak - Face glue up 3/4 stock and drill the pilot hole as per the instructions... After you've tapped, back the tap out and flood the threaded area with superglue and hit it with the accelerator or even some slow set epoxy and run a matching BOLT through a couple of times. I've been using a couple of my custom chucks for about 2 years... Sure frees up the faceplates.