Re: Epoxy nut ?

Dave, The problem with not using moglice is that most epoxies shrink
enough to lock up your "assembly" no matter how well you lube it.

Here's a trick and a tip: Us good al' fashion petrolium jelly as your
release-It's great with epoxies! Then put some graphite powder on a
chip brush and FLICK a nice layer of graphite on the THIN film of
vaseline. Gently blow the excess off. This is an old mold maker's
trick. The graphite powder will become the actual surface of the nut
because the epoxy will grab it.

Now the epoxy: The common mistake is to look for the strongest,
hardest epoxy. Wrong. The key is knowing that the epoxy's main
function is as a BINDER. So you want an epoxy with the highest
ADHESIVE STRENGTH you can find that's also very low viscosity because
you want to minimize the epoxy and maximuze the fillers yet end up
with something pourable. If you mix 40/60 graphite powder with a very
fine aluminum oxide powder and get good epoxy, the result could be
near what you would get with moglice.

BTW, you can get all that stuff free by requesting samples and you
can get the Moglice Handbook (a must) free as well.

Rick L.



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
<dave_mucha@...> wrote:

>
> Hi all,
>
> I have a garage door opener with a nice 8 foot multi-start screw.
>
> I want to make a nut for in and instead of trying to cut the screw

to

> make it into a tap, I would like to make a form and fill in epoxy.
>
> Any suggestions what epoxy would wear well ?
>
> And any suggestions on a release agent ? I was thinking silicone
> spray, but not sure if that is the best.
>
> I figure I would be safe by casting this on one end were there is

no wear.

>
> Dave
>