FR2 is the brownish material that many cheap circuit boards are made of. It's a mixture of phenolic resin and paper. Apparently it's quite useful to make gears out of:
Phenolic Gears exhibits superior shear force, help reduce machinery noise, absorbs destructive vibration unlike metal gears, phenolic is non-conductive, protects the mating metal gear train, and are known to outlast metal gears under severe continuous service. (source: https://www.knowbirs.com/phenolic-gears )
Has anyone seen these used anywhere? I've read a hint regarding pool equipment, but I have never seen them there. I assume the fibres allow them to last longer than plastic/resin only gears.
@Gronk @WaterWaiver
I printed 2 gears for my 7x12 lathe out of a filament from Igus.
https://www.igus.com/product/20322?artNr=I190-PF-0175-0750
Been in use for over 5 months and from inspection are in good shape. Quieter and unlike the originals durable. One is sacrificial and will shear if the lathe jams. When I jammed it it loaded the motor pretty heavily then let go so it did work. Some replace that gear with a metal one but I wanted the sacrificial feature so I do not blow the motor and speed control.
You need a heated chamber and they recommend heat treating it before use which I did not do since I was not certain it would not change the dimensions.
They have a few other filaments that are also useful. I went to this after multiple attempts to 3d print delrin. Even made a wood bed and finally gave up.
It's not cheap but I still have over 90% on the reel left after printing 3 gears.