@georgef posted:Thanks, That should give me enough info to make a couple.
It looks like there is about one inch left on top of the threads.
Rocky: Delrin is fully machinable just like a piece of billet metal would be.
It's best to machine it on a lathe. I've run into difficulty with it trying to deep bore it with a drill bit on a drill press. A plunge cut on a lathe would likely eliminate the problem but I sold my lathe a few years ago.
It has greater yield strength then most aluminums and is often used on race cars to replace rubber bushings since it is not as harsh on the ride as the old brass/bronze ones were like in the Comp Cobras.
I've torn door knobs off of doors inadvertently but can't hurt this knob so apparently it is gorilla tested safe?
Delrin does have the characteristic as never feeling hot or cold so it largely doesn't absorb heat or cold. I just made a couple of fuel logs out of it for that reason and the cabs on a hot running engine feel cool to the touch so the fuel isn't absorbing heat anywhere which is a huge plus on trying to restart a hot engine in a hot climate.
I'm sure if I look I can find the flexibility data on it but for a short item like this knob it's approaching perfect. The only question would be what diameter to make since many like me would feel more comfortable with a larger diameter rather then smaller but when you order the stock, you need to presume a certain outside diameter for it but you could play around with on a lathe with different shapes if you started out with a large enough diameter piece?
It's also a little slick in it's fully finished form and naturally polishes up very well as a result. You could polish it to make it have a finish like a Baldwin piano if you wanted that effect? It does kind of resemble "polished ebony wood"?
It does give the "artist" some alternatives to explore. It's good stuff and because you thread the material itself as if it is metal, it has no inserts to come loose.