12-23-2009, 02:36 AM
Hey,Ron - try spraying your master with lacquer. I've heard this is the way to keep your paint coating from reacting with the mould,and making it turn out gooey. Make sure that you've sprayed your master with automotive primer,as real lacquer - not acrylic will eat any finish that isn't lacquer based as well. Acyrlic is NOT lacquer,but it will suffice for a barrier against the mould surface while moulding. You just want to make sure that the product IS lacquer,as not everyone who claims it is on the can actually makes true lacquer!
This is highly toxic to the nervous system,and it's something you don't want to spray inside your house! I use plastikote brand,as this IS a true lacquer based coating,and not an acrylic clearcoat in a high solvent base,as most manufacturers make claims to the contrary on their labels today. Most paint is now highly regulated by the EPA,and lacquer is on top of that list. Meaning that this is one of few coatings that most paint manufacturers DON'T MAKE,as this requires special licensing,and manufacturing processes that are extremely expensive. This is also highly flammable - don't use this around any fire producing appliances. Unfortunately,most people don't know the difference between laquer,and acrylic,as they believe everything they read on a label without knowing the truth - lacquer is NOT a generic product any more than a brand name is!
Enamel,and acrylic can be mixed together without fear of ruining paint formulation. Lacquer on the other hand,can't be. It's too acidic,and won't mix with other binders! You can spray it over anything - wood,metal,plastics,but NOT OVER OTHER TYPES OF PAINT. It causes enamel,and acrylic to wrinkle,and lift. Unlike these paints,laquer can be resprayed at any time without fear of wrinkling. The solvents in it need to escape for a few days before attempting to cast anything with it.
I don't know what kind of reaction it may cause if used too early before curing. It actually takes a year to fully cure,but not to use. This just means that full hardness takes six months to a year to achieve. Most finishes take a while to cure,but since lacquer is an organic based finish it takes longer to reach full hardness,but it can be used in just a few days. Normally,you can use it in twenty four hours after use,but something as sensitive as,silicone - I'd wait for the smell to not be as strong before you use it.
This is highly toxic to the nervous system,and it's something you don't want to spray inside your house! I use plastikote brand,as this IS a true lacquer based coating,and not an acrylic clearcoat in a high solvent base,as most manufacturers make claims to the contrary on their labels today. Most paint is now highly regulated by the EPA,and lacquer is on top of that list. Meaning that this is one of few coatings that most paint manufacturers DON'T MAKE,as this requires special licensing,and manufacturing processes that are extremely expensive. This is also highly flammable - don't use this around any fire producing appliances. Unfortunately,most people don't know the difference between laquer,and acrylic,as they believe everything they read on a label without knowing the truth - lacquer is NOT a generic product any more than a brand name is!
Enamel,and acrylic can be mixed together without fear of ruining paint formulation. Lacquer on the other hand,can't be. It's too acidic,and won't mix with other binders! You can spray it over anything - wood,metal,plastics,but NOT OVER OTHER TYPES OF PAINT. It causes enamel,and acrylic to wrinkle,and lift. Unlike these paints,laquer can be resprayed at any time without fear of wrinkling. The solvents in it need to escape for a few days before attempting to cast anything with it.
I don't know what kind of reaction it may cause if used too early before curing. It actually takes a year to fully cure,but not to use. This just means that full hardness takes six months to a year to achieve. Most finishes take a while to cure,but since lacquer is an organic based finish it takes longer to reach full hardness,but it can be used in just a few days. Normally,you can use it in twenty four hours after use,but something as sensitive as,silicone - I'd wait for the smell to not be as strong before you use it.