January 2, 2014 at 6:31 PM #509
After you shape a hold with clay, foam, or whatever can you just goop silicone bathroom caulk out of a caulking gun all over it and make a mold? Seems like it would work if you can get it thick enough and not mess with it till it drys. How about making a dam around the hold with some cardboard then gunning the caulk around the hold? If this won’t work, what are some really inexpensive ways to make molds?January 2, 2014 at 10:17 PM #512
I am far from experienced in this, but I don’t really think there is such a thing as a good cheap mold. I think that there are a couple main reasons that regular caulking is not adequate for making a decent climbing hold mold:
1. The caulking is too thick to pick up the details and textures of your foam master, leading to poor texture and/or voids in your mold. Also not sure how well it will cure through on a bigger or thicker mold.
2. The silicone is not a high enough quality to have a long casting life. If you only want to make one hold or experiment with the process fine, but I have yet to hear of anyone getting good results with this type of silicone.
Maybe I will whip up a crappy hold out of scrap foam and try it just for fun, and compare its performance to the molds I have made with good quality 2-part rtv silicone, but I suspect there will be no comparison.January 6, 2014 at 7:45 PM #521
Please do! That would be a cool experiment. I am guessing 100% silicone bathroom caulk is cheaper than the 2 part, right?January 6, 2014 at 10:57 PM #581
tried. not worth the effort. Didn’t cure all the way for me after 72 hours, and even if I did the caulking has crap tear strength so wouldn’t demold well, I suspect you would not get many casts from this kind of mold even if you could get it to kind of workJanuary 6, 2014 at 11:31 PM #582
Thanks for testing it out!January 23, 2014 at 8:41 AM #616
I think that if you used caulking in many thin layers it might kind of work. maybe. kind of. I think when I tried it was too much at once and it needs exposure to atmosphere to cure. Regardless I’m not sure it would produce a worthy result.January 26, 2014 at 8:30 PM #617
Maybe if the mold wasn’t very thick in the first place? 1/2 inch? Make a really tight dam around your sculpted hold?January 27, 2014 at 8:18 AM #712
caulking won’t cure thicker than about 3/16 at a time I don’t think, so I’m thinking you would have to brush/rub it on in 3-4 applications letting it dry in between. Still if you are hoping for professional results with this method I think you would be disappointed.