Things continue to move along. I've about got my wax mold making process sorted. Time to figure out what I'm going to do regarding a vacuum chamber. Everything I've read says I'm going to want to degas my investment after it is mixed, and then degas the whole flask after it is poured. Problem is, my flasks are going to be fairly large. Still haven't worked out the final dimensions, but something like 12" x 7 " x 10". Ish. Probably need the vacuum chamber to be even taller than 12" to allow for the investment to "grow" as it's vacuumed. Don't really know where to start with this. I can buy vacuum pumps easy enough, but a little looking around makes me think that a dome big enough for what I need is going to be ridiculous money. Should I just build an airtight box out of MDF and put a clear hinged lid (with a gasket) on it?
No, search "Vacuum Chamber" on eBay. You can buy a 5 gal stainless drum and air compressor for $140. I bought an 8 gal because I need the extra height. I was amazed how well it actually worked and held high vacuum. Best, Kelly
Kellys method is the least pain in the ass and works. (that thing really come with a vacuum pump AND tank for 140bucks?) But if you need cheap, a garage sale pressure cooker will do the same job if you are creative. Or this. Don't forget your coupon. https://www.harborfreight.com/2-1-2-half-gallon-pressure-paint-tank-66839.html I agree, Domes are stupid money. I have one, but it was free.
https://www.ebay.com/itm/5-Gallon-V...356919?hash=item1cee9d17b7:g:6YwAAOSw4ABfD~mZ This is decent considering the cheap pump is 90bucks at the hazard fart!
Excellent. Thank you, Gentlemen, for the direction! Just ordered this one: https://www.ebay.com/itm/353283330481 5-gal, $103. (Suspiciously cheap, honestly, but we'll see how long it holds up.) The dimensions are going to be super tight. Corner to corner, my flasks (the current iteration of the design, anyway) are right at 11". This thing says it's diameter is 12". I'm guessing that's the outer diameter of the pot, and I'm hoping that the walls aren't thick enough to matter. So it be close, but should make it. That gets to another question: How much clearance do you think I need from the edge of one of these disks (the part being cast, that is) and the edge of the flask? My maximum diameter for the casting is 7.25". To make everything fit, I've got my flask at 8". If you look at it from the top, it will look like this: 3/8" seems pretty snug to me, but I have no experience with that, so that's just a gut feeling. Any thoughts? The issue I'm fighting is I want to A) minimize the volume of the flask so as to use as little investment as possible and B) end up with something that will fit inside the chamber and C) have enough flange area so the flask can seal to the casting vacuum chamber. (The flange isn't shown in that diagram. I'm planning on one 5/8" wide around the outside perimeter of the flask.)
just saw this.. the deceptive picture makes it look like it comes with the pump.. It does not. This explains why one is 103bucks and the other 165. Hope I didnt screw that up on you.
Good catch. The bastards. Cancelling now... Ordered the one you linked earlier. Should have ordered that the first time.
