PRODUCT REVIEW: Smooth-On casting material
website: http://www.smooth-on.com/
Products tried:
1. Casting starter kit:
thoughts: A great beginner's casting kit that affordably introduces the novice caster to the easiest methods of casting resin reproductions using 1 and 2-part molds. Both the RTV rubber and the plastic resin are the very simple to use 1:1 ratio so no scales or other precision measurement tools are required. The book is sold separately for $3.00, and is worth the money for the wealth of information it gives the beginner. The casting resin, the 1:1 quick-setting (4-minute setup) is just a little less viscous than Alumilite and easier therefore to mix, but not as thin as Micro-Mark's. It seems to bubble more than Micro-Mark's, too, but is perfectly usable. Just be prepared to fill in any air holes with putty following the cast. The weakest part of this kit is the universal mold release. Unlike Micro-Mark's, it comes in a spray which, while handy the first couple of times it is used, can't be resealed tightly enough to prevent it from losing strength over time. Still, that's a lot of goods to come in a $20 package ($20 from Smooth-On's website for first-time buyers only)--perfect for the novice who is interested in getting his or her feet wet in RTV molding and resin casting, but doesn't want or need to make a huge investment in case it turns out casting is not for them.
2. Rubber mold - a 1:1 rubber mold
thoughts: I picked this kit up by mistake, thinking it was RTV mold (NOTE:
always read labels, even when you're in a hurry). This kit is usable only if you
have a vacuum form kit to go with it, cause regular air drying will just not cut
it. Too many bubbles. Also, this is not to be used with porous originals or
without the use of a good mold release. This stuff is sticky as anything. Best
for casting metals, not for plastic. $20.
3. Casting resin - 1:1 mix, tan, quick setting
thoughts: Very similar to the white quick-setting plastic, but of course, the
resulting resin is a very light tan. It is also more viscous than the white for
some reason, and so is more difficult to mix (the most important step in casting
with this resin, particularly with the quick-setting kinds) and is therefore
more susceptible to air bubbles in the blanks. If possible, I'd recommend
sticking with the white mix since the color difference is very slight and the
white formula is a little easier to work with. $20.
4. Oomoo 30 RTV Silicon Rubber 1:1 4-hour cure time
5. Smooth-Cast 300