A casting acquaintance relayed this vid to me. Nice molding work and results. I like his trophy pile at the end. Worth a sub and taking in his other videos. Best, Kelly
Sort of a reversal of loose-piece molding using petrobond loose pieces—-sort of. Never have seen that method before. Very nicely done and an idea to hold onto. You’d look at the bell and think lost wax. Thanks for posting. Denis
Me too. But, now I see this sort of method is used by others (and I suspect is a “classic” method) in making complex shapes like statuary. I’m hoping a “need” arises soon for me to use that sort of method. Denis
I would love to know what the sand mix is! How the devil did the sand hold together, when he lifted the mould parts away with his trowel? Most impressive!
I guess you are referring to the Szobor video. I am pretty sure the first video of the bell is petroband for the "loose pieces." The Szobor guy seems to be using some sort of green sand. Who knows how he tweaked it with clays and maybe corn starch. Probably there are other possibilitiues that someone will pop up with. The tradeoff is probably less porosity for each added.ingredient. That might be counterbalanced by using coarser sand? Like you said, so many interesting unknowns. One thing I did notice in the bell video was the molder used a fork-like spatula (evidently ground from a kitchen knife) seen at 5:08 in the video which was sort of reverse-ground from the usual end profile so that it was quite concave rather than convex with points on each outside corner. I guess that is to reduce the tendency for the spatula to spread/split the bit of sand while he lifts it off. Also a bit of info I will try to retain. Denis
Thought ocurs to me that that "Petrobond" might well be "Delft Clay" - which is similar as to makeup, the differences being using silica (?) flour, 2× other ingredients. Is that metal brass?
First thing I would try for the loose piece cohesion is some tiny fiber. Wood flour or plastic mini fiber (kind of like nylon lint), used in epoxy work should do. Regular dryer lint might do, teased apart and worked into the petrobond.
mitakenly posted this same info in another thread. But it really belongs here. Using plain petrobond and a quick and dirty 5 minute trial: Not saying I have mastered by any means. But it does suggest this is doable with ordinary materials. Denis
