You can find Mesquite Man's (Curtis') tutorials for making a mold and a mold rack (to hold the mold in the pressure pot) on his web site with these links:
Making a Mold
Rack Plan
Couple of personal opinions on those tutorials:
- the cutting boards I'm finding locally these days are thinner than Curtis found when he made that tutorial. TAP Plastics has the thicker stuff. Using the thinner material is likely to cause the screws to stretch/bulge the plastic and those bulges will show up in your castings. Mostly, they'll be in areas that you'll turn away but if you're trying to sell your castings, those might detract.
If you have a Sam's Club, that is the best source for the cutting boards. They are also the very cheapest source for 1/2" HDPE that I have found. I have a wholesale account with a plastics supplier for my business. I priced buying 4x8 sheets of 1/2" HDPE just like the cutting boards. I broke down the pricing to the square inch and found the cutting boards from Sams to be cheaper!
- his mold plan makes a large block (two blanks thick by five blanks wide, ten blanks total). That's a lot of resin used/wasted when you're new and trying to figure out how much dye is required to get the colors you want or how to swirl the colors to get cool effects. It's worth also making a narrower mold (2 or 3 blanks wide) and filling it only half way for your first few batches...
The molds I give the plan for are designed to make 5 blanks, not 10. I always make my molds deeper than needed and suggest everyone do the same. Makes it MUCH easier to handle the filled molds if the resin level is not close to the top.
- the mold rack is overly complex. Odds are, you'll only put one mold at a time into the pot, so a two-layer rack with folding handle isn't realistic. Skip the middle layer, put the top horizontal (thin) piece lower, and just put a solid piece straight across the top where the pivots currently mount. It'll go together far faster, will work just fine, and you can skip the fancy pivoting parts.
I do my racks much different now and agree those are more complete than necessary! I also only do one shelf rather than two. It was fun engineering those at the time and doing the plans though!
Casters don't seem eager to post recipes for various colors/effects. Expect to experiment to find what works for you...take lots of notes!
When you're working with small batches, and want to scale the results to a larger batch (using Curtis' full-sized mold), make sure you scale up the amount of dye used as well.
Doubling the amount of resin requires doubling the amount of dye to keep the colors the same. Seems obvious, but when you're experimenting with overcoming the effect of the white Alumilite, and you think you know what the final amount of dye will be so you think you're also ready to step up to a full sized batch...make sure you scale properly.
It's easy to double the resin and the dye without catching that you wanted a darker color so you might have to triple the dye while doubling the resin when working with the white stuff.
The white Alumilite is clear until it goes off. So, colors look great during mix, but come out considerably lighter when the resin goes off.
The clear Alumilite looks great with mica powders and metallic powders! Doesn't take a lot of powder though you should expect to experiment a bit there as well...
If you make a smaller mold, expect to have to figure out how much resin you should mix...a couple trials blocks should get you what you want fairly quickly.
Or simply multiply length x width x height x .554 and that will tell you pretty close how much resin you need to fill that space.
Make sure the screws in your new molds are TIGHT. Yes, this seems obvious, but you may be very surprised at how quickly the resin can leak out if you have a screw loose. :biggrin:
