Features:

  • MIX RATIO: 1A:1B BY VOLUME - Easy to use silicone rubber compound features a convenient one-to-one by volume mix ratio, no scale is necessary *Packaging may vary*
  • SHORE A HARDNESS: 30 - This scale measures the hardness of flexible rubber molds. A 30A hardness is in the soft to medium soft range, between the flexibility of a rubber band and pencil eraser
  • POT LIFE: 30 MINUTES, CURE TIME: 6 HOURS - This product cures at room temperature with negligible shrinkage. Best to store at room temperature, see "For Best Results" section below
  • LOW VISCOSITY FOR EASY MIXING AND POURING - Great for making simple one- or two-piece block molds, no vacuum degassing is necessary
  • PERFECT FOR ART AND INDUSTRIAL APPLICATIONS - Often used for molds to reproduce sculptures and other prototypes, casting plaster, resins, and wax
Mixes 1:1, just like epoxy!

I do a LOT of silicone mold making. For years, I've used the "10 parts base mixed with 1 part activator" stuff. Now, I'm not complaining about those type of products--they make fantastic molds when mixed correctly that last for years and years. It's just the weighing of the base liquid and they never seem to give you enough hardener. The Smooth-On Oomoo uses a different kind of base and hardner--you mix the parts 1 part A to 1 part B, just like epoxy. It is a lot easier to measure, mix and pour. It has a faster demold time as well. I'm used to mixing and pouring molds and then leaving them overnight. With the Oomoo,I was able to mix and cast in the morning and unmold by early afternoon, Over all, I couldn't be happier. Oomoo isn't the perfect answer to all my molding needs, but it is a darn good one and I'll be using this a LOT more in the future.

Throughly mix, and you shouldn't have tons of issues with curing

This product was absolutely wonderful in short. I've read several reviews on different sites saying it goes bad after a few months after purchase, or that it was already bad when it arrived. However, the one I received was sealed and the contents inside were in excellent condition. I highly recommend purchasing from amazon. As long as you thoroughly mix (I'd recommend mixing in one cup, then pouring into another to get the stuff and the bottom also fully mixed) the product works great with resin and clay. For resin though I'd recommend putting on a thin glaze of polyurethane after because certain resins can react to this model of silicone.

Looking for something else to mold now!!!

I have gotten into pen making on my wood lathe, and needed a cheap, and easy way to cast my own acrylic pen blanks. This mold making kit made my life a lot easier. I just mixed up equal parts (BY VOLUME, NOT WEIGHT) of the silicone and poured it into a mold with a piece of wood roughly 1"x1"x6". I let the mold cure, and sure enough, it came out perfect! I didn't use any special release agent, but I did make my mold containment out of butcher plastic table scraps I had lying around. The wood came out very easily as well. I never knew it could be so easy to use. Now I am looking for everything and anything that I can be made into a mold. Truly fun and easy to use.

Works well but use it all within a short period.

Smooth-On Silicone Mold Making, Liquid Rubber OOMOO 30 is easy to use and makes a perfect mold. I used my mold for clay slip. The part was a thin part and it worked perfectly however for larger or thicker clay slip parts I cannot say if a silicone mold would be the best choice due to lack of experience. I do know that plaster is used for clay slip molds because it absorbs some of the moisture in the clay slip. I recommend stirring both parts separately while in the respective containers before combing together. Then stir both together for 3 minutes. This material needs to be used quickly or it will become too think to use.

Satisfied

I used this for a hawkgirl cowl I had sculpted and molded and I think it worked pretty well (not sure if this is the product you really use for this kind of thing) when you mix the 2 parts it comes out purple, the pink is just poor mixing on my part. The blue half, which I think is part B, came in chunky and thick so I was concerned about it working, but once I mixed it was fine. It did seem to cure faster than the 30 minutes that is advertised but overall I'm pretty happy with it. I was able to make this buying one set

Surprisingly good results from first time pour

First time user, went with mold release and the 300 for a longer cure time but didn't take proper advantage of it. Had a mold with lettering, where small looped letters (P, B, R, A) were common. Long pour wasn't sufficient to fill all these, though results were *far better* than expected. Next time I'll pre-fill using a syringe, then pouring over the top. May also need vacuum treatment - again the nature of the original making this far more tricky than most starting molds. I'll be casting a second mold using a syringe with the same 300, and expect that the results should be far better. As a first time user my only regret is not getting two boxes of this size.

Pros vs. Cons

This item is what gets the job done. Guys listen, when it comes to detail, look no further. Let me give you a rundown on the pros/cons on this. Pros- Simple. Cons- Messy. Pros- Equal measurement mixture; e.g. 3 oz.cup silicon + 3 oz. cup hardener + 6 oz. cup to mix in = 6 oz. cup of rubber mold. Cons- Pricey. Pros- Molds around every small detail, nothing can hide from it. Cons- Hardener is slower to pour. Pros- After mixing, (if portions are equal) you have roughly 3Hrs. to pour before it hardens. This gives you plenty of time. Cons- When mixing, air bubbles can and will get caught in it. It's unavoidable. Pros- Car resin (used for fiber glass body repairs) can be used for it, and not stick nor cause any damage to the mold itself. Cons- Unfortunately, some mold will have to go to waste, either by miss-measurement or by residue stuck in the cup mixture. I'd say the Pros won this fight. And the worst Con was the price.

Worth every cent

I tried a variety of mold making putties and rubbers available through big box craft stores, facing disappointment every time. I was hesitant to try something like this, since I had no experience working with silicone, but it's been a fantastic experience, and the only issues I've encountered were due to my negligence. While the silicone was much thicker than I expected, it takes to details beautifully, letting me replicate the tiny features of dollhouse miniatures perfectly. I haven't had issues with bubbles forming, save for my own mistake of creating a mold of a resin piece too freshly cast. The resin continued to outgas after it was covered in silicone, resulting in tiny bubbles that made that particular pour of silicone useless. It goes farther than I expected as well, and after creating 4 or 5 molds in the bottom of a cracker box, I still have 3/4ths of the containers remaining. I was concerned about one mold curing correctly because I failed to mix the bottom of the cup as thoroughly as I thought, resulting in a streaky mix of marbled blue and pink. Though it took longer for that mold to cure, it did cure properly, and I've not had any issues in the dozens of castings I've already made with it. Though the silicone mix is low-odor, I have chemical sensitivities and use an OV/P95-rated respirator when mixing and pouring, as the smell of a curing mold in my workshop did give me a headache after only a few minutes of exposure. Always make sure your work space is properly vented. Use of a respirator is encouraged in the instructions, but as many crafters overlook respiratory protection in their projects, I feel it's important to mention that it can make you sick if proper precautions are not taken! In all, I'm completely satisfied with this purchase and look forward to using it a great deal more in the future. I could have saved a great deal of time money by investing in this first, instead of being put off by a product I'd never used and considered too advanced for my uses!

Like warhammer or warmachine plastic/metal miniatures

So I'm using this to cast minis. Like warhammer or warmachine plastic/metal miniatures. It's a great starting place to build molds and the silicone picks up every single detail. Like, if you had your finger print on one of your models and cast it? You'll see every groove. It's amazing! Yeah it's a bit pricey, but silicone isn't cheap. Yeah they're other silicones out there too, but if you're some random person who wants to just cast yourself a personal collection of space marine shoulder pads or maybe you want to make some scatter terrain for infinity? This is a great product to work with.

Best 2 part molding rubber you'll ever buy

I would like to say that this is by far the best 2 part casting rubber ever made. All you have to do is thoroughly mix equally and pour about 8 inches from the mold. The detail is immaculate and there are no air bubbles in any part of the cast ( I did use a quick pass of a heat gun after pouring to help though) worth every penny

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