Yep. That's right. I am about to change your mold-making technique forever. This simple way of silicone mold-making will have you wanting to make casts of all your trinkets and toys.

You will need:
  • water
  • blue dish-soap (any brand seems to work)
  • 100% Silicone (do not buy quick set silicone, you need 100% silicone)
  • bowl
  • caulking gun
  • something you want to make a mold of.
  • scissors/knife
  • masking tape - to patch holes in your positive, if necessary.

Step 1: Make your catalyzing solution.

By mixing a high-concentration of dish soap with water in a bowl, one is actually making a catalytic bath for your silicone. The glycerine in the dish soap accelerates the cure process for of your 100% pure silicone.

This is by no means an exact science, I use blue dish soap because it allows me to see how much I have added to a water bath, I approximate that I used 4 oz. of soap in 64 oz. of water.
<p>I tried several times to make a mold from a ceramics figurine (unglazed) I made for the project. But the silicone always sticks way too good to the figurine, thus not leaving a very smooth mold. Also very hard to get out.<br>I never tried to cure it in soap water first, but do you really think that would make the trick? I tried to cover the figurine in oil first, but made no difference.</p><p>Now I just have a figurine with a lot of silicone residue all over it, and I can't figure out a way to clean it off efficiently so I can start over</p>
<p>Ceramics as in heat resistant? Silicones are known to be almost in-destructable by chemicals (there are some nasty bases that actually dissolve silicone but nothing houshold-grade). Most silicones however start to degrade at 300&deg;C. You could try to put your figurine on a barbecue grill and see if it can burn-off the residuals. </p>
Its a stoneware figurine, so defiantly heat resistant, as it was burnt at 1250&deg;C :P<br>I'll try that, thanks!
<p>Have you tested a wax coating to prevent silicone sticking to the piece?</p>
<p>Ceramic is a pretty porous material, even when glazed sometimes, and the silicone loves to stick to it for that reason. In my experience, using the soap water bath will not change the unfortunate results very much if at all. I don't know a good method of cleaning a silicone stuck figure besides burning the silicone off and I wouldn't advise using ceramic objects for this process, ceramic just doesn't want to play nice with silicone.</p><p> If you are still bent on casting it, you could maybe coat the ceramic figure with some sort of resin after it is cleaned to give it a less porous surface...? Something to look into perhaps!</p>
Is there a way to make some sort of silicone socks to cover steel table legs that are too sharp? Thanks
<p>This worked for me in a slightly different use.</p><p>Collect wax paper, cut into the shapes you want your final form to be.<br>Apply silicone to the table foot, stick on the wax paper and form or mold it into the final shape you want. Let it dry, pull off the wax paper and you will see your silicone in exactly the shape you created.<br><br>Roll the wax paper around the siliconed led for a cylinder shape.<br>Or cut and box wrap around the leg for flat faces and bottom.</p>
<p>Are the mould flexible? I am hoping to use it for some concrete projects, and I think some flexibility would certainly help to demould. Thanks!</p>
<p>i want to make a mold of a large leaf, will this work and is it pliable?</p>
<p>really great idea for making wax positives for metal casting.. if you're making art projects you can turn out several small bits of add on decoration...and the ability to grab something off the shelf and use it on spontaneous rainy day projects with the kids is impressive. thanks for the ideas.</p>
<p>Not to be a negative nancy... But why not just use made-for-purpose silicon mold compounds? e.g. http://tiny.cc/ultrasil (aside from the 'use what you've got lying around' benefits of course ;)</p>
<p>can you use this for food?</p>
<p>Not advisable, there are a few places in the comments where I talk about this not being a smart choice for food-grade use. Check out SmoothOn's food-safe molding materials.</p>
<p>Rubber companies only submit one of their formulas to test for food safety - it's very costly. Silicones are considered safe, and I'd use them for home food use, but for commercial/restaurant use you could only use the tested/approved silicone.</p>
<p>Two? types of silicones. Tin catalysts and Platinum catalysts. Tin based definitely not OK for food but cheaper than platinum based ones - which generally are. It will say on label if it is safe for food. Doesn't say = not safe.</p><p>This instructable is about Acetic acid (vinegar smell) curing tradesman silicones. Not safe for food but not as bad as tin based silicones either.</p>
<p>would this mold making tutorial work if I wanted to make a mold for some ear gauges ?</p>
I used to use Fimo for making earrings to stretch my ears.
<p>Absolutely not. Look for &quot;ComposiMold&quot; it is food grade, reusable and fairly cheap, for food grade. http://www.walmart.com/ip/26678575?wmlspartner=wlpa&amp;selectedSellerId=0&amp;adid=22222222227018919968&amp;wl0=&amp;wl1=g&amp;wl2=c&amp;wl3=40946670992&amp;wl4=&amp;wl5=pla&amp;wl6=78888318872&amp;veh=sem</p>
I love this way. I covers mine w/ pertrolium jelly, does the trick. Thanks. K
<p>I'm trying to add a silicone 'lip' to an existing dustpan, to make it pick up the little dust bits better. Do you think the silicone would attach? Should I score up the edge of the dustpan to make it adhere better? Should I put the silicone straight on, shape it, and let it cure, or use another method? (If there's a better place to be asking this in, please let me know!)</p>
<p>Silicone sticks to almost anything, but polyethylene is almost impossible to glue to. Maybe start with a dustpan made of something other than polyethylene.</p>
<p>Hey, how about Sugru? Google it and check it out.</p>
<p>Silicone will stick to that dustpan no-prob. I would score it and clean it with alcohol first. If you need to shape it into a lip, maybe look at some <a href="">grout tools to help you get the shape right.</a> For this use case you could even use quickset silicone, and never mix it with water or soap.</p>
<p>By packing plasticene against one side of the grater you block all the holes. You make the mold of the metal side, and when it's cured, you remove the plasticene, apply a mold release (thinned vaseline perhaps) and make the other side of the mold, Both sides need a mother mold. But, OK, WHAT IS THE POINT? a silicone rubber grater won't grate anything.</p>
<p>I usually just mix in some corn starch. Silicone reacts with moisture in the atmosphere to cure and makes acetic acid as a byproduct (hence the strong vinegar smell). Cornstarch absorbs atmosphere water so you mix it in and it is the water donator for reaction and will make sure that the silicone cures throughout and not just a skin on the surface.</p>
<p>Hi! Is this project good to use with metal products??? I am thinking of making a silicone grater, but I don't want to ruin a perfectly good grater. Thanks</p>
<p>A silicone grater? Like what one uses to make grated cheese? I have no idea how you could mold that and demold it. Too many small holes and features.</p>
<p>I would like to try this, but I know some types of silicone make the resin cast into them have a shiny finish, and some matte. I really want shiny finish, do you have any advice on the silivone for that? THank you! </p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>Great ible! Can you use wood or rubber as the positive for this type of mold?</p>
<p>What brand of casting resin did you use?</p>
I am pretty resin agnostic. These days I go for a resin that's not going to stink up my house, with low VOCs. The <a href="http://amzn.to/1Sswwmu">Castin Craft 1:1 kit</a> &nbsp;is moderately less fumey, but it also depends on the size of your cast.<br /> <br /> I have been working with the <a href="http://amzn.to/1UIA4Y8">Solarez Casting Resin</a> to make small parts for jewelry lately, its a lot less smelly than some other stuff I have used.
i think he was talking about silicon who smell bad. It have a vinegar kind off smell
<p>Thank you!</p>
Question...so the finished piece you showed is only 1/2 of a dinosaur? Can you explain how to create a mold with 2 halves? Or is that covered in a separate post? Thank you!!
<p>thanks for the idea!!! Is the mold reusable? </p>
<p>Followed the directions here and got great results. Silicone does take about ten minutes to before its ready to shape. You might want to make a small box out of cardboard to create a rectangular mold and glue your model down with hot glue, depending on what you are making.</p>
<p>Am i able to cast Soma Foama 25 from smooth-on?</p>
<p>Great idea to have fun creating a mold at a fraction of the price required with commerciol products. Works well with wax positive as well, see the picture</p>
<p>i cast these 'vintage' light sockets from an original; these were cast in plaster. mold was extremely easy to make and worked exactly as described here. it was so easy i cast additional molds to speed up the plaster casting process!</p>
<p>those came out great!</p>
Tried a third batch with epoxy resin in these almost 2 weeks after i made them. Still no luck. Surface doesn't cure. I know it's not the ratio of resin and hardener, as pieces from the same mixture cured perfectly. I've been trying to find answers everywhere to remedy this. I think the silicone is releasing alcohol and it's interfering with the surface cure, from what I've come across. Has anyone tried baking these? I need to dry them out somehow, and air drying isn't working.

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