Have never done it so I do not know for sure. But experience doing fiberglass stuff would seem to suggest that answer is no. Resin alone over softer materials is easily cracked. While I will admit cob is stronger than the stuff I am comparing to unless there is fiberglass in it, it is very fragile. Molded fiber glass over plaster of paris at one point and just gently taping on the resin to break it loose from the plaster.(was using a silicone mold release agent.) easily broke the resin where I didn't have glass fiber in the mix. You might try resin and glass mat. I have a friend who built a cedar strip ocean kayak. It was covered in 3 layers of resin and 2 layers of glass mat. The glass mat just barely showed in the resin and it was clear enough to still mostly see the grain in the cedar strips underneath. From a couple of feet away the glass mat was invisible except in a few places.
Another possible you might check the RMH cob information. I think it was on permies but it might have been somewhere else. They were talking about hardening and toughening cob using a mixture of blood, milk and boiled linseed oil painted on and let soak in. Apparently it stunk while hot for a while but it dried down to a really tough outer layer after multiple coats. If it isn't on permies maybe someone on the RMH boards
knows where it was posted.
He puts the "turd" in "saturday". Speaking of which, have you smelled this tiny ad?
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