> I'm taping my outer shears, and I'm prepared to put bulkheads/cockpit
> coaming/footpegs/etc. on in pretty short order. How long do I need to wait
> for the epoxy to get a good cure before I can start the major sanding? I'd
> like to at least get the feathering of the roughest spots done.

> Also, what's the best method for feathering? It took me about an hour with
> the random orbital sander with 60-grit just to smooth out the outer shear
> prior to the taping. Is the fairing board with 60-grit a better method?

> Thanks,

> Dean

Hi Dean,

I am usually chasing drips and fairing with a carbide bladed scraper after each coat while the resin is still green and easiest to work.

After the weave is filled I let the epoxy come to a full cure so that the epoxy is good and hard before sanding. How long you wait before sanding depends on your epoxy and the ambient temperature - check the manufacture's instructions.

I use a ROS [at a medium setting] and 80 or 100 grit paper. With a medium speed setting and well cured epoxy I can use the finer grit paper [which has more cutting edges] to level the surface and have no problem with the paper clogging. After the initial leveling I wet sand with 180 grit followed with 220 and 340 grit in preparation for varnishing.

Most ROS fixed speed sanders are geared to sanding wood and are too fast for epoxy. Spidey mentioned an add-on speed control was available, might be a good thing to invest in if you don't have a variable speed sander.

If you have a problem spot, don't concentrate on it too long. Move around to avoid heating up that area.

Don't always assume that the coarsest paper will remove the most material. Different types/brands of paper cut differently. Try a couple grits and chose the one that works best with your equipment, epoxy and style [speed & pressure] of sanding. You will quickly see/feel/hear what works well and you will know right away when the paper becomes dull and needs to be replaced. Select the grit to suit material being sanded - generally, the finest paper that does not clog will do the best job.

Hope this helps.

Hank