# Thread Chasing Help



## Thorn495 (Feb 28, 2014)

I want to try making wood threads. Sorby sells a set with varying tooth per inch (TPI). I was wondering what set to order (10, 16, 20 TPI)? Want to mostly make screw on bottoms for hollow forms that have roughly 1.5 - 2" diameter holes at the bottom. Any tips or advice for what thread chasers to get?


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## Bill Boehme (Feb 9, 2014)

I think that 16 TPI is a good starting point for hand chased threads.

Having said that, you are setting yourself up for failure. Most wood that is suitable for hollowforms isn't suitable for thread chasing. Thread chasing requires even textured hard wood like rosewood and cocobolo. There might be one or two domestic hardwoods that are suitable.


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## saculnhoj (May 18, 2015)

Bill is correct. You need a very hard wood. Most people use hard wood inserts such as Blackwood, Cocobolo, or Boxwood. I have also poured epoxy into grooves, let it harden and then turn away the wood and cut my threads in that. 
16TPI is a good thread for learning and pretty good overall especially for that size opening. 
I used PVC pipe for practice chasing threads. It cuts well and of course costs very little. You can't reallly turn matching male and female threads because the pipe sizes won't accomodate it. However you can practice both threads. 
When you get really good you can chase threads in softer woods. My friend Mark StLeger frequently chases threads in Hard maple and sometimes even Cherry. I'm not there yet. I end up with crappy looking threads in those woods. 
There is another option. Buy one of the threading jigs. I use the Baxter threader from www.bestwoodtools.com I know it's expensive but when I bought mine I just turned and sold enough threaded lid boxes to pay for it. YOu can cut threads in very soft woods with success with this tool.


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## Thorn495 (Feb 28, 2014)

saculnhoj said:


> Bill is correct. You need a very hard wood. Most people use hard wood inserts such as Blackwood, Cocobolo, or Boxwood. I have also poured epoxy into grooves, let it harden and then turn away the wood and cut my threads in that.
> 16TPI is a good thread for learning and pretty good overall especially for that size opening.
> I used PVC pipe for practice chasing threads. It cuts well and of course costs very little. You can't reallly turn matching male and female threads because the pipe sizes won't accomodate it. However you can practice both threads.
> When you get really good you can chase threads in softer woods. My friend Mark StLeger frequently chases threads in Hard maple and sometimes even Cherry. I'm not there yet. I end up with crappy looking threads in those woods.
> There is another option. Buy one of the threading jigs. I use the Baxter threader from www.bestwoodtools.com I know it's expensive but when I bought mine I just turned and sold enough threaded lid boxes to pay for it. YOu can cut threads in very soft woods with success with this tool.


That is expensive. Are there other things you can use it for besides thread cutting? I ordered some Sorby 16 TPI chasers. I'll give that a shot first.


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## saculnhoj (May 18, 2015)

This threading jig is considerably less expensive. Not anywhere near the quality but I have one of them also and it seems to work. Kind of like the difference between driving a BMW and driving a Ford. Both get you there but it's a lot more fun in the Beemer. 
http://www.chefwarekits.com/ez-threading-pro-xl-jig-thread-cutter


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## Thorn495 (Feb 28, 2014)

I got the thread chasers to work with plastic and PVC pipe to insert the piece I needed. The gentle approach wouldn't work on PVC and I just got a rhythm down going across it somewhat aggressively. I tried the chasers on some rock maple, but it won't thread to a sharp point; it leaves a rounded, shallow thread when I tried that. 

I found a neat gadget that Nova had out almost 10 years ago called an Ornamental Turner that could do threads, end and side decorative cutting in turning pieces. Looked very useful.

https://youtu.be/qZzRtEL7n4w

https://youtu.be/iiaCnPI3s9M

https://youtu.be/e8mrP4KJIi0

I might try to make something like that using a milling vice for a drill press.


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## Bill Boehme (Feb 9, 2014)

I can't make heads or tails out of the last picture. What is it?


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## pburri (Jan 17, 2014)

*cutting threads in wood*

I have successfully cut threads in soft woods. I thoroughly soak the work piece in thin cyanoacrylate glue to toughen the wood and then I used soap as a lubricant when cutting the threads.
Also, the coarser the thread pitch - i.e., 10tpi vs 16tpi will be stronger.


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## Thorn495 (Feb 28, 2014)

Bill Boehme said:


> I can't make heads or tails out of the last picture. What is it?


It's the bottom of a bowling pin birdhouse. I made another one for my grandma for Christmas with a screw on bottom too.


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## Thorn495 (Feb 28, 2014)

pburri said:


> I have successfully cut threads in soft woods. I thoroughly soak the work piece in thin cyanoacrylate glue to toughen the wood and then I used soap as a lubricant when cutting the threads.
> Also, the coarser the thread pitch - i.e., 10tpi vs 16tpi will be stronger.


Hmm. I might give the cyanoacrylate (?) glue a shot sometime if I can't make what I have work. I agree that a larger (coarser?) thread will stand a better chance than the 16tpi. 

I thought this guy had a pretty good idea: 

http://stusshed.com/2011/07/16/homemade-thread-chaser/

I have a 1 1/4" x 8tpi Beall tap that I used as a chaser with some pretty good results in wood that wouldn't make a decent thread with the 16tpi chasers, but don't think it would cut metal very well.

So I bought a 1 x 8tpi bolt at Ace Hardware that I'm going to try grinding and/or sawing into a chaser. I think it will work if I can cut and grind it right. The larger nuts and bolts come pretty hardened (so the guy at the store told me). Might be a frustrating time in the making.


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## saculnhoj (May 18, 2015)

That was me that did that article on building your own thread chaser. I found out after more experimentation that it's almost as easy to simply file the chasers by hand from scratch. 
2 methods that work pretty well are to take a tap of the thread size you want and simply grind away everything but the teeth. You've also made them by taking bolts and grinding away part of the them. I've brased or welded the bolts to other stock to give me the proper orientation for male and female thread chasers.
If you don't have welding capability you can simply silver solder the tap or bolt threads onto your blanks. Silver solder only requires a MAPP gas torch to do the job.


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