

⚡ Mold faster, craft smarter — the pro’s silicone secret!
Oomoo 25 is a tin-cure silicone rubber designed for quick, easy mold making with a user-friendly 1:1 mix ratio by volume. It cures in just 75 minutes at room temperature without the need for vacuum degassing, delivering smooth, detailed molds ideal for casting plaster, resin, wax, and more. Perfect for professionals and hobbyists seeking fast turnaround and reliable results in sculpture, jewelry, and prototype reproduction.
| ASIN | B01C4YQ4TU |
| Best Sellers Rank | #57,986 in Arts, Crafts & Sewing ( See Top 100 in Arts, Crafts & Sewing ) #496 in Sculpture Molding & Casting Products |
| Brand | Smooth On, Inc. |
| Color | Blue |
| Date First Available | December 4, 2013 |
| Full Cure Time | 75 Minutes |
| Global Trade Identification Number | 00751635822412 |
| Is Discontinued By Manufacturer | No |
| Item Form | Liquid |
| Item Package Quantity | 1 |
| Item Volume | 2 Pints |
| Item Weight | 3.15 pounds |
| Item model number | OOMOO25-2P |
| Manufacturer | Smooth-On |
| Material | Silicone |
| Package Information | Can |
| Product Dimensions | 6 x 3 x 9 inches |
| UPC | 751635822412 |
| Unit Count | 32.0 Fluid Ounces |
| Viscosity | low |
| Viscosity Level | Low |
| Water Resistance Level | Not Water Resistant |
K**E
Get this shizz if you wanna make cool mold stuff! Its pretty freaking cool!
This stuff is freaking AWESOME! Was super skeptical since I've never done mold casting like this before. I've done fiberglass and carbon fiber, but those are pretty straight forward. And especially since I was doing it on a coated surface that I couldn't find any information on whethe or not it would stick to it. So, this stuff can beapplied over a Plasti-Dip sprayed item without it sticking to it or anything, so it worked perfect for what I needed! Making shroud extenders for a projector retrofit, and needed to make a reverse of the vacuum form piece I already made. Sprayed it with Plasti Dip as a spot evener, and this stuff didn't stick to it or even tried to pull it of. Sweet! I was worried I would get the mix ratio wrong, or mess up a step, but it's really not hard, but this stuff is a chore to mix by hand. Oh! BE SURE once you've poured A and B together and mixed that you pour into a second cup, and remix and scrape the sides and get every bit you can because the different parts WILL stick to whatever you're mixing in. When I scraped out cup #1 into cup #2 there were still parts of blue and green not mixed all the way, so it's a definite MUST. A++, 5 stars, 100% what ever, I'm impressed , and have just have to buy more for the 2nd headlight.(wasn't sure how much I was going to need, so just ordered the one) Going to also be buying their smooth cast 300 for the actual cast piece once these puppies are all set up
S**N
Used to make mold for making wax masters of 3D printed part for casting
I used this material to make a silicone mold for a musket part that I wanted to have cast out of steel. To do this I had to make a wax master. I used Solid Edge CAD software to design the master, and then used it to scale the part up 3% to account for shrinkage of the steel. After filling and sanding the master smooth, I was able to pour a silicone mold around it. I used vegetable oil as a mold release agent. The silicone worked very very nice because I was not able to easily make a two-part mold for this part, and this part has undercuts that would make it hard to remove from a rigid mold. But due to the flexible nature of the silicone, once the wax solidified I could stretch the opening enough for the part to be pulled out, and then it returned to its original shape for more pouring. Being 2 parts equal volume to mix, it's very easy to mix this "by eye" without measuring. I had enough silicone to make 3 molds as seen in the picture. Few problems with bubbles, and the material conforms closely to the master and picks up all details. Sets up fast enough that you can use your mold the same day you cast it. I used a palm vibratory sander to vibrate the mold casing while the silicone was still liquid to help shake out any bubbles. Because I did not scale up the first master enough to account for shrinkage of both the steel and the wax, I am having to do this over again with a larger master. But I am buying this product again for round two! This was my first ever attempt at making a silicone mold and casting wax in it. I highly recommend this product.
P**A
Do not buy
Part A in my first order was solidified when I opened the seal so they replaced the whole product. When I got the replacement shipment I opened the seals to make sure the product was still liquid and it was. I closed both bottles and stored them for a few months. Decided to make a mold and found part A was clumpy and drying. Stirring wasn’t possible because there was hardly any liquid left, the product was lumpy, sticky, impossible to ‘pour’ out of the bottle. I’m very disappointed and wish I could return it but it is outside of the window. I would say don’t buy unless you plan to use it soon after you buy it. This has the shortest shelf life I’ve encountered in mold making products.
A**M
An excellent product when you get a good batch.
Found out that resin 3d prints do not like platinum cure silicone. People recommended the tin cure. I was on a time crunch and rolled the dice with this product. I got a good batch with no leaks delivered next day. This stuff is thick. Use a a flat screwdriver to mix the parts well before you mix them together. I broke off a wooden stir stick in one of the compounds. Make sure you stir the compounds together extremely well. Otherwise they won't set right. Next day it was solid and perfect. It did stick to my glass base plate so use a scraper for that. Overall very good buy for resin 3d printer parts.
J**.
excellent detail in mold
This produces an excellent silicone mold and reproduces fine detail, however it has a very limited shelf life prior to use. The batch received had thickened up more than my earlier use of the product, although still usable and produced an excellent mold. The mold casting is extremely floppy flexible and needs to be used in conjunction with a properly keyed mother mold (reinforced plaster of paris--suggestion: if you mix some Elmers/Titebond wood glue into the plaster when mixing it becomes very hard and strong)
E**Y
Stir, stir, stir and it’s perfect every time!
I have purchased a handful of these kits to mold small movie prop replicas. If you follow the instructions exactly, the mold will come out perfectly every time. However, I learned the hard way that if you don’t thoroughly stir/mix the two parts together, then the final bit of silicone in the very bottom of your container won’t properly activate to harden. This leaves the very top layer of the mold gooey forever and unusable. So be sure to buy a large bowl to mix the two parts together and stir thoroughly with a rubber spatula that you can scrap along the bowl to sufficiently activate all the silicone. In the end, the mold picks up every detail precisely with little to no bubbling. Highly recommend!
S**E
I never go wrong with smooth-on products, great quality and easy to use. This is my first experience using Oomo 25 and O was very pleased with the results, and fast set up time! As it is a tin-cure silicone, it is ideal for avoiding most things that usually cause silicone inhibition.
M**N
Product arrived earlier than expected, however when I opened the package, one of the silicone liquid has spilled as there was a cut on the ‘sealed’ bottle plus the cap was not secured tightly.
B**S
This product literally arrived unusable. Part A was fully cured in the container to the point that I could turn it upside down and nothing came out. Huge disappointment as this was needed for an upcoming project. Basically garbage as part A needs to be mixed with part B to actually make the silicone usable.
A**D
Used to create a mould for repairing an MDF cabinet door. Worked well. Got a tiny bubble in one spot, but I guess that was my bad.
H**0
They tell you to use it quickly... But not specific. Two weeks in and it was already drying out.
Trustpilot
2 months ago
2 weeks ago