Casting material suggestions

[Scarydog]

I have some experience casting small items and parts but have not done it in a couple years. 

Last time I used Tap plastics quick cast and was pretty pleased with the results. 

What I'm looking for is suggestions on the best vendor to buy such supplies.

2 part silicon for pouring molds

and 2 part resin for casting. 

Any suggestions?

[JMGraham]

If you like TAP, they're still kicking around and produce good products. Personally, I've grown to prefer Smooth-On. I use MoldMax 14-NV for my silicone, and SmoothCast 320 for my resin. 

[Scarydog]

23 minutes ago, JMGraham said:

If you like TAP, they're still kicking around and produce good products. Personally, I've grown to prefer Smooth-On. I use MoldMax 14-NV for my silicone, and SmoothCast 320 for my resin. 

And do you have a preferred vendor? 

[JMGraham]

40 minutes ago, Scarydog said:

And do you have a preferred vendor? 

I'm up in Bellingham, and I tend to buy resin in bulk. As such, my purchase habits aren't typical for the hobbyist. When I just need a "little bit" (10 gallons of resin, or 5 gallons of silicone) I mail-order from Farwest Materials : https://farwestmaterials.com/ . When I need more (50 to 90 or so gallons of resin), I place an order through Seattle Pottery Supply and drive down to pick it up when it ships in: http://www.seattlepotterysupply.com/

For smaller and more sane amounts, SmoothOn has vendors all over, and their trial kits are easy to mail-order, if you need to go that route: https://www.smooth-on.com/distributors/

 

[Justjokin]

+1 on the Smooth-On products.  I use Oomoo 25 for making molds, and Smoothcast 300 for casting.  Both available in the small trial sets that JMG mentioned.  

https://www.amazon.com/Smooth-OOMOO-Trial-Unit-Pint/dp/B00H3QO7K8/ref=sr_1_3?ie=UTF8&qid=1498675937&sr=8-3&keywords=oomoo+25

https://www.amazon.com/Smooth-Smooth-Cast-Liquid-Plastic-Compound/dp/B004BN7G0E/ref=sr_1_6?ie=UTF8&qid=1498675937&sr=8-6&keywords=oomoo+25

[JMGraham]

2 hours ago, Justjokin said:

+1 on the Smooth-On products.  I use Oomoo 25 for making molds, and Smoothcast 300 for casting.  Both available in the small trial sets that JMG mentioned.  

Fine suggestions! Smoothcast 300 and 320 are basically the same resin, save that 320 is re-formulated to be a bit better at taking dye. Which, of course, only matters if you're adding dye to your resin (I dye mine grey). They're the same viscosity (80 cps), and slightly more liquid than the (still excellent) TAP Quickcast (about 250 cps).

For silicone, keep in mind that the Mold-Max and Oomoo are pretty different silicones. The Oomoo is much harder than the 14-NV, has less tensile strength, and stretches less before breaking. Because I cast things in one-piece molds with a lot of undercuts, I need my molds stretchier and softer. While some folks have found the harder Oomoo silicones to be more prone to breakage, I think it really depends on what you're casting, and suspect that many of those experiences are because they used the wrong silicone for the model. The 14-NV is too soft for some applications (though, not nearly as soft as TAP's platinum-cure silicone). Keep in mind, also, that you need an accurate kitchen scale or the like for the 14NV (it's mixed by weight), while you don't for the Oomoo or other MoldMax (which are mixed by volume).

They are closing down the resin Addict Forum, but while it's there, it's an incredible source of information: http://www.resinaddict.com/forum/

Good luck, and post your results!

 

[Scarydog]

Thanks for all the suggestions 

I put in an amazon order this afternoon. 

 

 

[Justjokin]

6 hours ago, JMGraham said:

I need my molds stretchier and softer. While some folks have found the harder Oomoo silicones to be more prone to breakage

This!  

I've chalked my mold breakage over time to just age, but hardness of the silicone as well as environment that it is stored must really make a difference in the life of the mold over multiple casts.  Oomoo and the smothcast products are 1:1 mixes by volume, rather than weight(no scale, just graduated measuring cups).  That and very quick cure times are the reason that I find them the ones that I choose.  I have molds that have turned out 30 casts, but some that didn't even make it to 10.

I have found that when I take an original or cast and place it back in the mold and I store the molds level relative to how they were poured, they hold up better over time.  

 

11 hours ago, JMGraham said:

When I need more (50 to 90 or so gallons of resin)

I defer to any perspective this gentleman has at this point! :)  Having done a thing really counts for something!  I've bought your products before @JMGraham, top notch!