Threading questions - using tap/die set

[Jim Underwood]

Tonight I was playing around with my tap and die set and seeing what kind of woods would tap easily. This was all done into end grain. I did no cross grain threading. I used a 17/64 drill (or smaller the 2nd time) and a 5/16 x 18 tap/die.

For tapping inside threads, Maple and Osage Orange seemed to do pretty well. The threads look nice and smooth. I didn't try anything else.

For outside threads I found that Maple, Crape Myrtle, Privet, and Walnut really sucked. They didn't make threads at all once I ran that die up on them..

The Bloodwood tried, but in the end it was too brittle and crumbly. The Osage Orange worked the best, but it still didn't make very nice threads...

My questions are these:

Is there a way to keep those outside threads from crumbling? Is there a trick to it? Can I apply CA glue and keep them together? Are some woods better than others? If so, what are they? Do I need to have really sharp taps and dies?

[Dick Strauss]

Jim,
End grain tends to strip very easily because the orientation dictates that you are actually cross-cutting the grain "straws" at many places along their length. This situation doesn't provide much holding power.

IMO you are much better off with a side-grain orientation for cutting threads in wood.

Think of driving a screw into wood. End grain doesn't hold well while cross-grain holds really well. The same is true for threading applications.

[Jim Underwood]

True, but I'm trying to make little boxes.... And they seem to work best if you turn them in spindle orientation.

[Bill Stevener]

Taps & dies for steel will not work for wood. You must have taps and dies for wood.

[Travis Gauger]

Taps & dies for steel will not work for wood. You must have taps and dies for wood.

I agree with Bill. I have had really good luck with cherry, maple, and birch. I use a wood threading kit I got at woodcraft for about $30. works quite well actually. The thing is, the die for steel has 4 to 8 different cutting surfaces to shape several thread grooves at the same time. The wood threading kit is cutting a single thread groove while your turning the wood through it.

[Jim Underwood]

Hey guys, thanks for the comments. I had posted this on two other forums and had some good suggestions. I'm going to give those a try, but I also had another totally different idea due to your comments. It was a combination of the "you can't do that" and "it works better this way" that set off my idea... When I try it, I'll post the results back here.

Mr. Stevener, I'm glad you told me "you can't do that" because now I have to prove that I can. I'm just stubborn like that.

Actually y'alls comments made me rethink, or really think about it, and it all clicked...

[Phil Thien]

Taps & dies for steel will not work for wood. You must have taps and dies for wood.

I've had outstanding luck w/ a 1/2-20 tap in wood. Never tried a die.

The only problem w/ the tap is that it will wander. You need a pilot. A center finder of the appropriate hole size will work, but a pilot would work better.

[Jason Hallowell]

Taps made for wood will work better, but the best results come from using live tooling, which would be very difficult on a wood lathe. I've done lots of threading of wood parts, but all work was done using live tooling on a metal lathe.

[Jim Underwood]

I'm assuming that by "live tooling" that you mean you are using the screw cutting abilities of the metal lathe?

[Bill Stevener]

Hey guys, thanks for the comments. I had posted this on two other forums and had some good suggestions. I'm going to give those a try, but I also had another totally different idea due to your comments. It was a combination of the "you can't do that" and "it works better this way" that set off my idea... When I try it, I'll post the results back here.

Mr. Stevener, I'm glad you told me "you can't do that" because now I have to prove that I can. I'm just stubborn like that.

Actually y'alls comments made me rethink, or really think about it, and it all clicked...

Jim, you will not be the first, thousand have tried long before you. It's worth a try to invest in the taps and dies maid for wood if you have projects to warrant them.
There are threaded inserts maid for wood that work very well.
If your idea works out, Pat. it, you will become millionaire.

Bill.>>>

[neil mackay]

Jim,

Taps and dies can work after a fashion on timber. But your gonna have to be very selective on the timber you use.

The main reason is the metal working taps and dies are very aggressive on the timber.

The ususal hand held chaser variety is often the best as it allow far more control ove the thread cutting and comes generally at a low price tag.

Heres a couple of pics on one from another forum of a 2 in 1 set up

neil

[Jim Underwood]

Well it worked.

Only have time to tease you now... Photos tomorrow.

[Jason Hallowell]

I'm assuming that by "live tooling" that you mean you are using the screw cutting abilities of the metal lathe?

I was using the thread cutting capabilities of the lathe, but that's not what live tooling is.

Live tooling refers to a spinning cutting bit rather than a stationary one. Threads are rather small, and a stationary cutting tool can tear and stress the wood fibers making the threads weak. By having the cutting tool moving at very high speed, most of these stresses are removed, making for much stronger (and smoother) threads.

A common way to live cut threads is to mount a laminate trim router in the toolpost. Here is a pic of what it looks like in action, and a pic of the cutters used-

[Jim Underwood]

Ok... I gotcha. Live tooling=Moving bit. Makes sense. That setup is similar to Jean Michel's homemade rig. I plan to make one of those soon.

But, I did want to experiment with the taps and dies to see what could be done. I'll post some pix today - I promise.

[Wilbur Pan]

Taps & dies for steel will not work for wood. You must have taps and dies for wood.

So what's the difference between tap and dies for steel and tap and dies for wood?