Threading Bakelite

[Timebandit]

In need of some help. As most of you know i have been doing the kitless thing lately and i have something in the works. I was trying to thread some Bakelite yesterday with my 10x1mm die trying to make a front section and very easily cracked the tenon cutting the threads. I turned the cap first and taped it with the same size and it tapped perfectly. I made my tenon between 9.8 and 9.6mm so it was undersized to give me a little clearance and still cracked the threads.The Bakelite has aged a little bit and has a little bit of yellowing so is could just be that it is really brittle. It did want to chip out a lot while turning the cap. Everything else i have threaded with this die cut fine as these same dimensions.

Any tips from you guys? Anyone have experience threading Bakelite? I remember skip saying the other day that he heats some resins up in a glass of hot water. Im wondering if this would help with this Bakelite. In wondering if the best way to cut the threads would be to machine them on a metal lathe so i could take really small passes and sneak up on the thread depth.

Any tips would be greatly appreciated.

Thanks

Justin

 

[BRobbins629]

Bakelite is one of the tougher materials to cut threads with a tap and die. Its too expensive to keep cracking so I wound up making inserts from black ebonite and threading that. Alumilite, PR, brass, silver, etc will also work.

 

[IPD_Mr]

Bruce is correct. Even if you do manage to get it threaded, it will most likely crack somewhere down the road. Ask Roy about Bakelite cracking.

 

[Timebandit]

Bakelite is one of the tougher materials to cut threads with a tap and die. Its too expensive to keep cracking so I wound up making inserts from black ebonite and threading that. Alumilite, PR, brass, silver, etc will also work.

Are you talking about a insert in the cap or a ebonite section on the front of the pen body where the threads are being cut. The cap threaded just fine, it was when i went to cut the mating threads on the tenon where everything went wrong Luckily i did this on a small piece for a front section and not on the pen body:frown: Problem is that i want to make a front section as well but have to cut threads on it.

Bruce where you trying this on a metal lathe or using taps and dies?

 

[Timebandit]

Hmmmm.... bummer. Guess i might have to give it a try on the metal lathe. If that doesnt work i guess i will just have to think of something else

Anyone else????

 

[BRobbins629]

Bakelite is one of the tougher materials to cut threads with a tap and die. Its too expensive to keep cracking so I wound up making inserts from black ebonite and threading that. Alumilite, PR, brass, silver, etc will also work.

Are you talking about a insert in the cap or a ebonite section on the front of the pen body where the threads are being cut. The cap threaded just fine, it was when i went to cut the mating threads on the tenon where everything went wrong Luckily i did this on a small piece for a front section and not on the pen body:frown: Problem is that i want to make a front section as well but have to cut threads on it.

Bruce where you trying this on a metal lathe or using taps and dies?

Here's how I did it - with tap and die. Inserts are ebonite.

 

[Timebandit]

Bakelite is one of the tougher materials to cut threads with a tap and die. Its too expensive to keep cracking so I wound up making inserts from black ebonite and threading that. Alumilite, PR, brass, silver, etc will also work.

Are you talking about a insert in the cap or a ebonite section on the front of the pen body where the threads are being cut. The cap threaded just fine, it was when i went to cut the mating threads on the tenon where everything went wrong Luckily i did this on a small piece for a front section and not on the pen body:frown: Problem is that i want to make a front section as well but have to cut threads on it.

Bruce where you trying this on a metal lathe or using taps and dies?

Here's how I did it - with tap and die. Inserts are ebonite.

Yeah, doing it like this was a last resort, but i was just going to segment the two materials rather than tapping and threading them. Dont see the need for all of that. Also then you see the black through the Bakelite( at least on yours and other more transparent Bakelite). Why did you decide to thread it all?

I guess i just wanted an all Bakelite pen, front section and all. I guess i am just a dreamer:tongue:

 

[BRobbins629]

Why did you decide to thread it all?

It's not all threaded - only the parts of the cap and barrel that mate. The other joints are mortise and tenon.

If you don't want to the black to show through, make the tenon on the more transparent material and you won't see it. I've made the mistake of doing it the other way a few too many times.

 

[Timebandit]

Why did you decide to thread it all?

It's not all threaded - only the parts of the cap and barrel that mate. The other joints are mortise and tenon.

If you don't want to the black to show through, make the tenon on the more transparent material and you won't see it. I've made the mistake of doing it the other way a few too many times.

Do you think the tenon is necessary? Wouldnt just gluing the two together be fine?

 

[BRobbins629]

Do you think the tenon is necessary? Wouldnt just gluing the two together be fine?

When you glue 2 pieces together there is very little surface area at the joint by the the time it is drilled and turned. It may hold, but the tenon joint it much more secure. Why risk it?

 

[apple320]

Here is how I did mine

It had no clip as it has it's own leather case.

The section is acrylic and the bakelite only has internal threads on it so it is fairly strong.

Chris

 

[Dan_F]

Do you think the tenon is necessary? Wouldnt just gluing the two together be fine?

When you glue 2 pieces together there is very little surface area at the joint by the the time it is drilled and turned. It may hold, but the tenon joint it much more secure. Why risk it?

I agree with Bruce, it may hold initially, but will give sooner or later, probably sooner.

Dan

 

[Timebandit]

Thanks guys

Chris that might just work. I doesnt give me the full bakelite pen(no front section) but i does give the look on the outside. You can still see the threads through the material a little, but i think that will all depend on the transparency of the bakelite i have.

Thanks for showing