What does RTV-2 mean?
Two components when mixed together cure at room temperature (RTV= room temperature vulcanization).
Do I need to use a mold release?
Yes, on the original, and when trying to separate two silicones halves. Silicone will only stick to itself and it does it quite well. We offer MR-15 as a release. You do not need to release your reproductions as silicone once it is cured is self releasing.
Do I have to deair/degas the silicone before pouring?
The silicone will work better if you vacuum degas it. By removing all the extra air you mixed into it, the silicone will pick up better detail and have stronger physical properties. All the properties listed on our data sheets are obtained from a degassed sample. However, degassing does not affect the curing.
Do I have to weigh the silicone?
The products are formulated to react using a measurement based on weight. If you attempt to measure by volume, you will get different results from those shown on the data sheet. Most of silicones have a volume ratio listed on the data sheet.
What is the shelf life?
The shelf life of the uncured material is six months. The “library” life, that is the life of the cured silicone, varies from product to product, and you should check with the factory.
Does temperature effect the silicone and how it cures?
Yes. The GI-series silicones will lose work time and cure time in the presence of heat and humidity. They will gain work time and cure time in the absence of heat and humidity. The P-series will lose work time and cure time in the presence of heat only as well as gain work time and cure time in the absence of heat. For more specific information, call the factory.
What causes the P-series to be “wet” at the interface?
Inhibition. P-Series silicones are inhibited in the presence of organo tin complexes (GI-series), sulfur, and nitrogen. If you are unsure of the makeup of the master, mix up a small amount of P-Series silicone and test it on the master. Contact the factory for assistance if you have inhibition, or prior to use if you are unsure.
Can inhibition occur with the GI-series silicones?
To date, we are not familiar with anything that causes inhibition with the GI-series silicones and the standard catalysts. Although solvents or wet masters can cause a delay in the cure at the interface, the silicone will cure.
How can I make the silicone cure faster?
We offer catalysts for both the P-series and GI-series which will decrease the cure time. But remember if you decrease the cure time, you will also decrease the work time!