Best blanks for practising threading?

[ibex]

I'm just starting out on the kitless journey and I expect that there will be a few failures in my initial cutting of threads. I don't want to waste the more expensive quality blanks while I'm learning how to do this so are there any recommended cheaper types of blanks for practising on?

Locally acrylic blanks seem to be the cheapest but I've seen reports that acrylic is not really suited for cutting threads.

 

[showcaser]

I'm just starting out on the kitless journey and I expect that there will be a few failures in my initial cutting of threads. I don't want to waste the more expensive quality blanks while I'm learning how to do this so are there any recommended cheaper types of blanks for practising on?

Locally acrylic blanks seem to be the cheapest but I've seen reports that acrylic is not really suited for cutting threads.

It has more to do with size of tenon and size of hole drilled. Ebonite threads wonderfully. Here is a Aussie Bespoke Pen facebook group that are very helpful too. https://www.facebook.com/groups/2945511102377964

 

[ibex]

It has more to do with size of tenon and size of hole drilled. Ebonite threads wonderfully. Here is a Aussie Bespoke Pen facebook group that are very helpful too. https://www.facebook.com/groups/2945511102377964

Thanks. I didn't know about that group. They've let me join

 

[Displaced Canadian]

Alumilite and other epoxy resins thread very well. Fiberglass type resins can be problematic. I found that most hexagonal dies don't work well for cutting new threads.

 

[PatrickR]

Acrylic threads fine while being a little brittle. Ebonite is more forgiving, but if you can thread acrylic successfully ebonite will be a breeze. With acrylic undersize the tenon a little and if you need to tighten the die any do it in very small amounts.
hexagonal dies are made to repair existing threads not cut new ones.

 

[its_virgil]

Acrylic acetate works well. About
3-4 $ per blank.

 

[MedWoodWorx]

what about stabilised wood?

 

[ibex]

Acrylic threads fine while being a little brittle. Ebonite is more forgiving, but if you can thread acrylic successfully ebonite will be a breeze. With acrylic undersize the tenon a little and if you need to tighten the die any do it in very small amounts.
hexagonal dies are made to repair existing threads not cut new ones.

I saw there were two types of dies but hadn't realised that the hex ones were for repair. Thanks.

 

[showcaser]

Thanks. I didn't know about that group. They've let me join

Thanks. I didn't know about that group. They've let me join

Enjoy, a great group of people there.

 

[duncsuss]

In my experience:

Thread ok/nicely: acrylic acetate, polyurethane resin, epoxy resin, galalith (casein)
Thread best: Alumilite, celluloid, cellulose acetate (Cebloplast)
Difficult to thread: inlace acrylester, polyester resin (includes most "ivory substitute" products), bakelite

By "difficult" I mean somewhere between "forget it" and "I won't try again unless a customer cannot be convinced to choose something else".

I learned/practised on acrylic acetate - saw some on clearance and bought lots cheap, which made it a painless learning curve.

 

[Herman]

I made several acrylic pens with sucess. Just apply a cutting fluid, the holes must have a suitable diameter for each thread.

 

[PatrickR]

I saw there were two types of dies but hadn't realised that the hex ones were for repair. Thanks.

I have not found threading most plastics to be difficult (see Duncan's post above). Lubricate liberally, size the tenon accurately, polish the tenon and return first, do not run the die tight to the return. If swarf comes away looking dry it's been under lubricated. Once the threads are cut run the die back and forth quickly to polish the cut. I do this by laying my hand on the holder and push/pull quickly. I finish by cleaning away the loose swarf, lubricate and use a piece of sewing thread to polish the minor areas by pulling it back and forth with a sawing motion through all of the threads.

 

[Aurelius]

Alumilite and other epoxy resins thread very well. Fiberglass type resins can be problematic. I found that most hexagonal dies don't work well for cutting new threads.

Just a heads up, the hexagonal dies are generally for cleaning up existing threads, not cutting new threads.
You want to use round dies for cutting threads.

 

[MedWoodWorx]

In my experience:

Thread ok/nicely: acrylic acetate, polyurethane resin, epoxy resin, galalith (casein)
Thread best: Alumilite, celluloid, cellulose acetate (Cebloplast)
Difficult to thread: inlace acrylester, polyester resin (includes most "ivory substitute" products), bakelite

By "difficult" I mean somewhere between "forget it" and "I won't try again unless a customer cannot be convinced to choose something else".

I learned/practised on acrylic acetate - saw some on clearance and bought lots cheap, which made it a painless learning curve.

stabilised wood falls under the epoxy category?

 

[duncsuss]

stabilised wood falls under the epoxy category?

I find it difficult to make good looking threads even if the wood is stabilised.

The best results I got were when I made the tenon smaller than normal - so that the peaks of the threads were flat on top (not sharp like this: ^^^^)

It meant there was less contact between the parts that screw together, but the visible threads looked better. (You can't really see the threads inside the hole - which is probably a good thing!)

 

[farmer]

The harder woods thread better then softer woods using a die or a tap .
Take small turns and back off . clean the wood cuttings out of the tap or the die at all times .
You can't go to slow or take to small of cuts ..
NOTE I said cuts not tearing the wood ......
I use car wax or Vaseline to lube the wood/die/tap. as I am cutting the threads.
Coarser threads cut in better then fine threads on wood .
They are cut in beeper ..