What is this material?

The first time I used a lathe was at school, 20 years ago, the material I used I don't know what it was.

It was black rod and had a polished finish, it cut like plastic, but the outside finish was patchy grey and black, almost like carbon fibre. When cut the bar was black, so the grey was just on the outside?

Glass impregnated Nylon perhaps?

I used it once to make some panel stand offs,and looked and machined like you describe.

No, I've used GF nylon in injection moulding. The scarf was long and soft, GF Nylon swarf would be brittle and hard I imagine.

The grey patches were around 10-20mm randomly but regularly spaced from memory

Sounds Like Hard rubber?

Often patchy grey black

**LINK**

Regards
John

Ebonite?

Sounds like Ebonite, often used for knobs on electrical instruments.

Clive

Is that quote a rigid material?

The piece I used was 6 foot long x 1.25" diameter with not much flex along its length.

Could it have been black delrin. I have some bits that have a greyish mottled outer surface but are solid black when cut.

Doug

Nylatron, maybe?

Anna

Send me a couple of feet and i will confirm the item.

Clive

Yes, sounds like Nylatron to me as well, it's common enough.

Could be, can you post a picture when you have a chance please.

Unfortunately it was around 20 years ago and I no longer have it.

Could be Nylatron, I'll have a better look later, thanks.

Here's a photo of a handle I made from a piece of Nylatron rod. As can be seen in the short upright piece, the mottling is not very deep.

Hi Chris- I would love to post a picture of the delrin but I have recently installed windows 10 and my old card reader has stopped working with the computer. Just had a good look at the delrin and the mottled surface appears to be extrusion marks on the surface and looks a bit similar to the nylatron picture but more banded.

Doug

Dear Chris

Did they really never tell you what it was you were machining? Bearing in mind schools don't normally have huge budgets for this sort of thing, it can't have been from a wide choice.

Let's see now... black, maybe grey, cuts like plastic? Something 'ny-lony' it has been suggested? Sort of thing they are making troll suits from these days, I imagine.

Best

Martyn

I don't know what the troll suit means?

Mr White didn't know what it was, I do remember him telling me that all the material they had was donated.

He seemed to trust me to do anything, I was the only student allowed to use his solder remover, also the only person allowed to use the Harrison lathe unsupervised, no idea why. Strangely I now have the same Harrison lathe in my workshop.

Chris,

Could it have been a black grade of Tufnol? There were black grades a few years ago and one or two stockist still offer some but it appears to be becoming obsolete

Bob D

I don't think it was Tufnol.