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moonpie
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I have a big plug I'm ready to mould. After so many failures with easy lease I was going to use pva. The plug is sealed with s120 and has a clean smooth finish. When I apply pva though it fisheyes like its a wax resist crayon picture and I get bad patchy coverage. Is there something anyone can recommend to prepare the surface for pva application? I always pre clean with EC mould cleaner so it should be contaminant free...thanks
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beliblisk
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+xI have a big plug I'm ready to mould. After so many failures with easy lease I was going to use pva. The plug is sealed with s120 and has a clean smooth finish. When I apply pva though it fisheyes like its a wax resist crayon picture and I get bad patchy coverage. Is there something anyone can recommend to prepare the surface for pva application? I always pre clean with EC mould cleaner so it should be contaminant free...thanks Perhaps sealer has enough slip to make PVA fisheye (one that i use from Chemtrend makes sourface quite slippery on its own) . You could apply some wax befor pva or/and if you have the means PVA can be sprayed. For moulds i always go wax/pva route. If applied nicely there isnt much to correct afterwards but its hassel free when it comes to release
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Hanaldo
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Why use PVA? If you've had issues with EasyLease and don't want to use a chemical release agent then that's cool, but why not just use release wax and avoid the issues of PVA?
PVA has it's uses, but for me it is only ever when you are using chemicals on surfaces that are incompatible with each other. So when using styrene based gelcoats on single pack or unknown paints, or natural rubbers, etc. But you have a surface that is chemically compatible with anything. So there's no need to use PVA, and it will only marr your surface finish or cause you the application issues you are having now. Release wax on it's own is a great release agent, you don't need the PVA.
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moonpie
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Group: Forum Members
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+xWhy use PVA? If you've had issues with EasyLease and don't want to use a chemical release agent then that's cool, but why not just use release wax and avoid the issues of PVA? PVA has it's uses, but for me it is only ever when you are using chemicals on surfaces that are incompatible with each other. So when using styrene based gelcoats on single pack or unknown paints, or natural rubbers, etc. But you have a surface that is chemically compatible with anything. So there's no need to use PVA, and it will only marr your surface finish or cause you the application issues you are having now. Release wax on it's own is a great release agent, you don't need the PVA. I guess I'm a bit nervous about just using wax too. I can't afford to trash the plug in the mould making process as it's taken me 2 years to get the shape perfect. ( I work slowly 😁). I'll try the meguiars gold wax then and see how we get on. Hope you're right Hanaldo 😉. Thanks for the advice.
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moonpie
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Group: Forum Members
Posts: 34,
Visits: 94
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+x+xI have a big plug I'm ready to mould. After so many failures with easy lease I was going to use pva. The plug is sealed with s120 and has a clean smooth finish. When I apply pva though it fisheyes like its a wax resist crayon picture and I get bad patchy coverage. Is there something anyone can recommend to prepare the surface for pva application? I always pre clean with EC mould cleaner so it should be contaminant free...thanks Perhaps sealer has enough slip to make PVA fisheye (one that i use from Chemtrend makes sourface quite slippery on its own) . You could apply some wax befor pva or/and if you have the means PVA can be sprayed. For moulds i always go wax/pva route. If applied nicely there isnt much to correct afterwards but its hassel free when it comes to release Thanks Beliblisk, not tried wax plus pva, I will test that out , cheers.
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LibertyMKiii
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+x+xWhy use PVA? If you've had issues with EasyLease and don't want to use a chemical release agent then that's cool, but why not just use release wax and avoid the issues of PVA? PVA has it's uses, but for me it is only ever when you are using chemicals on surfaces that are incompatible with each other. So when using styrene based gelcoats on single pack or unknown paints, or natural rubbers, etc. But you have a surface that is chemically compatible with anything. So there's no need to use PVA, and it will only marr your surface finish or cause you the application issues you are having now. Release wax on it's own is a great release agent, you don't need the PVA. I guess I'm a bit nervous about just using wax too. I can't afford to trash the plug in the mould making process as it's taken me 2 years to get the shape perfect. ( I work slowly 😁). I'll try the meguiars gold wax then and see how we get on. Hope you're right Hanaldo 😉. Thanks for the advice. I had bad experiences using only mold release wax by itself. My large mold with vertical walls also has been suffering from fish eye when applying the PVA. I was able to do 8+ light dusting coats with PVA to form a film of PVA. It worked well and protected the mold. I wish I could lay down a wet layer of the PVA, but it either fish-eyes or runs... I know how to shoot a good clear coat on cars so it was frustrating to me to not figure this out... I like the protection PVA provides so it will remain a love hate relationship.
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Hanaldo
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Group: Forum Members
Posts: 2.5K,
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+x+x+xWhy use PVA? If you've had issues with EasyLease and don't want to use a chemical release agent then that's cool, but why not just use release wax and avoid the issues of PVA? PVA has it's uses, but for me it is only ever when you are using chemicals on surfaces that are incompatible with each other. So when using styrene based gelcoats on single pack or unknown paints, or natural rubbers, etc. But you have a surface that is chemically compatible with anything. So there's no need to use PVA, and it will only marr your surface finish or cause you the application issues you are having now. Release wax on it's own is a great release agent, you don't need the PVA. I guess I'm a bit nervous about just using wax too. I can't afford to trash the plug in the mould making process as it's taken me 2 years to get the shape perfect. ( I work slowly 😁). I'll try the meguiars gold wax then and see how we get on. Hope you're right Hanaldo 😉. Thanks for the advice. I had bad experiences using only mold release wax by itself. My large mold with vertical walls also has been suffering from fish eye when applying the PVA. I was able to do 8+ light dusting coats with PVA to form a film of PVA. It worked well and protected the mold. I wish I could lay down a wet layer of the PVA, but it either fish-eyes or runs... I know how to shoot a good clear coat on cars so it was frustrating to me to not figure this out... I like the protection PVA provides so it will remain a love hate relationship. Yeh clear coats are formulated to blend and finish flat, PVA is not. Not to say having good spray technique won't help, but it just isn't ever going to lay down that well. Especially when you are spraying it on a mould that likely has a slick surface already, its just asking a lot. On a chemically compatible mould, wax on its own should be good enough. But it often requires more than the recommended number of coats. If im using wax in its own, I'll do a solid 12-15 coats. Which is why wax is such a massive pain in the ass, it takes a bloody long time. Chemical release agents are much much quicker.
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moonpie
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Well I bit the bullet and moulded without PVA. The plug had taken many months to model so was a bit nervous about getting either the mould or the plug out in one piece but decided to use wax on the top half of the plug and ez-lease on the bottom half. Both released from the plug well although the plug broke into three pieces coming out of the mould. The ez-lease half was done with 8 coats and released with no adhesion. The wax half was done with 10 coats and picked up a tiny piece of the plug in a tight area of detail but pretty good all told.
Now the bad bit! The flange created on the first half moulding I treated with 8 coats of ez-lease. When trying to split the mould the flanges were effectively bonded together so I almost had to cut them apart to get the two halves to separate. That leaves me with a big job now to re gel coat the damaged areas, something that never seems to give me a hard workable surface even using 2% wax in the gel coat mix. A long road now to build up the gelcoat and sand it flat with it clogging the sandpaper so quickly but on the up side, the mould surface itself is spot on!
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ats101
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Group: Forum Members
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+xWell I bit the bullet and moulded without PVA. The plug had taken many months to model so was a bit nervous about getting either the mould or the plug out in one piece but decided to use wax on the top half of the plug and ez-lease on the bottom half. Both released from the plug well although the plug broke into three pieces coming out of the mould. The ez-lease half was done with 8 coats and released with no adhesion. The wax half was done with 10 coats and picked up a tiny piece of the plug in a tight area of detail but pretty good all told. Now the bad bit! The flange created on the first half moulding I treated with 8 coats of ez-lease. When trying to split the mould the flanges were effectively bonded together so I almost had to cut them apart to get the two halves to separate. That leaves me with a big job now to re gel coat the damaged areas, something that never seems to give me a hard workable surface even using 2% wax in the gel coat mix. A long road now to build up the gelcoat and sand it flat with it clogging the sandpaper so quickly but on the up side, the mould surface itself is spot on! Hey man, when I touched my mould up with gelcoat without wax additive, I left it in the sun and cured nicely and quickly. I used an eletric detail sander
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beliblisk
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Group: Forum Members
Posts: 53,
Visits: 2.8K
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+x+xWell I bit the bullet and moulded without PVA. The plug had taken many months to model so was a bit nervous about getting either the mould or the plug out in one piece but decided to use wax on the top half of the plug and ez-lease on the bottom half. Both released from the plug well although the plug broke into three pieces coming out of the mould. The ez-lease half was done with 8 coats and released with no adhesion. The wax half was done with 10 coats and picked up a tiny piece of the plug in a tight area of detail but pretty good all told. Now the bad bit! The flange created on the first half moulding I treated with 8 coats of ez-lease. When trying to split the mould the flanges were effectively bonded together so I almost had to cut them apart to get the two halves to separate. That leaves me with a big job now to re gel coat the damaged areas, something that never seems to give me a hard workable surface even using 2% wax in the gel coat mix. A long road now to build up the gelcoat and sand it flat with it clogging the sandpaper so quickly but on the up side, the mould surface itself is spot on! Hey man, when I touched my mould up with gelcoat without wax additive, I left it in the sun and cured nicely and quickly. I used an eletric detail sander Or just flash tape over it (i normally use way more than 2% catalysts for touch ups)..... works great 
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