RyanSilva

Using rtv silicone, you will really only need the mold release for 2 part molds, and  Easy at home recipe is simply petroleum jelly, just graze the jelly surface to pick up most of the oils and spread away, you can mix it with mineral spirits to create a thinner substance but it works both ways.

Resin speed fluctuates with not only its mixing time of a specific brand/model resin you are using but also the temperature and mass of the object you are casting. thin walled items will set up slower than a thicker object but  the speeds arent very noticeable with a fast kicking resin. The biggest problem I see with folks casting items as a hobby is they use a fast set resin..and it really ticks people off when they get bad parts which is understandable, Most resin casters have been there.

While mold design and air key ways play a big part in how easily the air travels in and out on a mold, the big culprit is the fast set resin, how fast is yours? I recommend a medium speed resin without pressure pots, heck smoothon makes a very slow resin also that will give you 20 minutes of MIXING time..which if I was a patient person who wanted to get the most out of my resin with more than enough time to knock out most of the air bubbles. id use it. It has a demold time of 2-4 hours but that can be a bit longer depending on size of item and air temp.

Checkout smooth-on smoothcast 305 and 310 if you wanted to try a new resin.


Now the molds themselves, have any pictures? how are they vented? ive found when casting tires using 1 vent hole that is both a fill port and vent.  tap of the mold a few times on a hard surface when almost filled, will knockout the air pocket..however that's using smoothcast 305 medium set resin so i  got enough work time, you may not have that.

You can try putting your resins in the fridge before you mix to buy you a minute or two, some folks do that..i never tried it though.

If you need a quick release using household items, good ol vaseline/petroleum jelly works well,  just lightly graze a brush/your finger on the surface of the jelly to get its oils and rub the half of the mold.

Here is the original thread where it all started, I gave a small writeup with pictures of my mold and the slit. It's what I use for my resin and rubber tires..

http://www.modelcars...l=&fromsearch=1

Michaels use to carry plastikote till the valspar name swap happened, however the remaining lacquer went to clearance. I bought abut 10 cans for 2 dollars at  the few michaels I have in the area. last year