Epoxy Bearing Material and Method

[John Mac]

Hi All

Attached is a powerpoint I did for epoxy bearing material
It was presented in Melbourne Australia


A piece of threaded rod with epoxy nut described.
Cheers

I posted a copy of the file here:
http://www.mediafire.com/?xpdu1z75t6hm70a


Macka

[Tweakie.CNC]

Hi John,

I read your presentation but I am still unsure about what you put on the thread first to stop the epoxy sticking and how did you centre the sleeve on the rod while the epoxy cured ?

Tweakie.

[John Mac]

Hi Tweakie


The reason I had the screwed shaft in the lathe turning at a slow speed was to keep it wrapped around the shaft instead of running. Once that had gelled off in about an hour it was removed from the lathe and a large nut screwed on, with that nut at the bottom the rod was placed in a vice held upright. To fill the space between the coated screw and the collar straight epoxy mix was used. (Why waste metal powder) When filled another nut was placed over the collar and screwed tight.

The nuts had just the right amount of taper to centre the collar, not optimally but within about 10 thou. A better method would be to make a precision jig.

My workaround was to chuck the threaded rod and turn the collar in the lathe. Not a bad finish for an old scrap of water pipe. And now the steel collar is concentric.

In this test I used some Teflon Grease I had at hand. It worked ok.

I had a discussion with a fiberglass shell manufacturer.

He suggested carnauba wax applied then after waiting ten minutes polished off. (This process to be repeated 3 times) That is how he did boat shells.

Another person suggest silicone mould release. Again from the fiberglass industry.

Cheers

Macka