Another good find, John. The link below is to a page on RP 3260. The hardness of this product is very interesting. On the Shore hardness scale bigger numbers mean harder product. There are several scales for different materials. The table shows a Shore D hardness number of 88. The range of hardnesses for epoxies is generally 55-80 (http://www.matweb.com/SpecificMaterial.asp?bassnum=O1770), so this stuff is considerably harder than any unfilled epoxy.

But hardness is only part of the picture. By way of comparison, a Titleist DT golf ball is 57-59 (http://www.titleist.com/2410_dt_distance.htm#). Though considerably softer, everyone knows a golf ball is very tough. A good measure of abrasion is the Taber abrasion resistance test. A sample of the material is sanded with a rotary abrasive disk of known grit and weight, and the sample is weighed before and after to determine loss. But I could find no data on this product published on any of the websites I found. From your description of what it does to HS tool steel drills though, it must be formidable.

Tough stuff, indeed! Might be hard to find in small quantities, though. Anybody want to go halvsies on a 55 gal. drum?

: I mentioned the epoxy filled with carbide on the board a few days ago. We use
: to use it for a surface coat while making master molds that had a metal
: tracer constantly running over them and therefore had to be tough and
: vitally non wearing. On the plus side this epoxy (Ren Plastics RP-3260 )
: was so tough that it would easily destroy a high speed drill bit ( we used
: tungsten drill bits ) but the wear resistance was unbelievable. It could
: wear the rocks down before it wore down. On the down side it is an ugly
: blue (see picture) it is thick and we heated it under lamp to thin it and
: brushed it on. To smooth out sags or ripples after it is applied is very
: hard. Sandpaper hardly touches it and wears out quickly. I would say it is
: 20 time harder then the epoxy plastic we use on our boats. I have not
: found Ren Plastics on the net but I can get the address if anyone might
: want to experiment. Meyer Plastics Incs. , 8343 Clinton Park Drive, Ft.
: Wayne, IN ( also in Indianapolis and I think on the net) is another
: pattern shop supplier that would probably have something similar, but
: whether it would have the same amount of carbide in it or not, I don’t
: know.