Prior to designing a vulcanizer (assuming you’re only going to have 1
size) one of the things that has to be determined is what is the maximum
size of item you’ll be molding. The larger the mold size, the heavier the
vulcanizer needs to be.
Some typical sizes of mold frames can be found in most any jewelers tool
catalog. Rio Grande’s lists sizes with openings from 1 1/2 x 2 1/2 x 5/8"
to 3 1/2 x 4 3/4 x 1 3/4". The length & width of these dimensions must be
increased by 1 1/2" to allow for the frame wall thickness. Based on frames
with these dimensions you’d need a platen at least 5 x 6 1/4". These
dimensions don’t allow for any guide rods or clamping bolts on the sides
of the mold frames. If an allowance for a 1 " border is made, the platen
size becomes 7 x 8 1/4". The platens should be capable of opening at least
4" & closing to less than 5/8". If you make the platen too much larger,
it’ll take longer to heat up the excess metal mass.
For info on the temps required for the various mold rubbers check with the
supplier. Rubbers made by Castaldo vulcanize between 250 & 400F.
There are a number of videos & books on casting & mold making that may
give you some ideas for designing & building your own equipment. I’d
suggest getting a copy of Rio Grande’s (US,800-545-6566; Can,800-253-9738)
tool catalog. It has a good selection of tools, books & videos. Sometimes
better prices can be found elsewhere, but atleast you’ll have an idea of
what’s available & what the cost is.