Guitar Hero Hacks: Key Molding

Step 3 A high pour

Check over your mold and part to make sure there aren't any dust, grit, or fingerprints that will screw up your casting. Remember that whatever you see here will show up in your final parts, and there's no way to correct a screwed up mold. A few extra seconds of inspection will save you the massive headache of recasting the whole part.

Mix your silicone according to the manufacturer's specifications. For the OMOO the instructions called for equal parts of compounds A and B. Stir your mixture for at least a minute, making sure to scrape down the sides and bottom. Try not to whip bubbles into the mix by moving the stick in and out of the mixture.

One of the crucial factors in making a successful mold is making sure there are no voids or bubbles in your casting. This means you pour your mixture from high above the mold in a very thin stream. This stream will pop the large bubbles that would have been included in the casting. Start in one corner of the mold, and let it fill evenly to the other side. When you've poured enough that you can only see the top of your key, go in with the paintbrush, and make sure there's silicone filling up the small divits where the rubber bumpers were. Now you can fill the mold until your silicone is about 1/4" above the level of your key.