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Discussion Starter · #1 ·
Im looking for a good primer for flexible plastic? I got some flexible pieces (3 gauge pod pillar and lower valence) that Im getting painted and dont want it to crack. Friend said we can seal em and shoot em but I want em smooth like glass! I heard there are primers out there made specially for flexible plastics so I was just curious and use it as a option. Also is it sandable?
 

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i use SEM high build primer... it comes in a spray can.
 

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Discussion Starter · #4 ·

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i used dupicolor plastic adhesion promoter on my valance and it's holding up good so far. picked it up from napa.
 

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to get your valance smooth like glass your going to have to sand it down unless it came smooth. Start with 80, then 180 and finally 320, then primer. You can use the SEM high build primer and it shoud be fine without any flex addictives. I spray bumpers and moulding with it all the time and get no cracking.
 

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Discussion Starter · #9 ·
to get your valance smooth like glass your going to have to sand it down unless it came smooth. Start with 80, then 180 and finally 320, then primer. You can use the SEM high build primer and it shoud be fine without any flex addictives. I spray bumpers and moulding with it all the time and get no cracking.
is the SEM 39134 high builld? I heard u can use sealer also and it doesnt need to be sanded.......is SEM a good product or is there better? I guess SEM doesnt need a hardner or anything and HEARD thats no bueno LOL :crazy::hmm::think: It will be sprayed out of a gun also. If i do multiple coats and sand in between can I cover up texture on lets say the column???
 

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is the SEM 39134 high builld? I heard u can use sealer also and it doesnt need to be sanded.......is SEM a good product or is there better? I guess SEM doesnt need a hardner or anything and HEARD thats no bueno LOL :crazy::hmm::think:
Im using SEM's interior dye/paint for some of my interior parts and it seems to be a great product. IDK about their primer though.
 

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is the SEM 39134 high builld? I heard u can use sealer also and it doesnt need to be sanded.......is SEM a good product or is there better? I guess SEM doesnt need a hardner or anything and HEARD thats no bueno LOL :crazy::hmm::think: It will be sprayed out of a gun also. If i do multiple coats and sand in between can I cover up texture on lets say the column???
the one in that link is not high build... SEM is nice product, i used the high build for all my smoothed plastics and their dye for my headliner plastics.

you have to smooth before youre first coat of primer if you dont want texture to show in your paint. trust me it will show.:nono: you will also use less primer that way too.

use the orbital you have, it saves a shit ton of time.
 

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Discussion Starter · #13 ·
the one in that link is not high build... SEM is nice product, i used the high build for all my smoothed plastics and their dye for my headliner plastics.

you have to smooth before youre first coat of primer if you dont want texture to show in your paint. trust me it will show.:nono: you will also use less primer that way too.

use the orbital you have, it saves a shit ton of time.
Ya I smoothed my upper/lower dash completely that was fun! U know the # for high build? I think the 39134 will work good on my valence and top bumper cap.....
 

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is the SEM 39134 high builld? I heard u can use sealer also and it doesnt need to be sanded.......is SEM a good product or is there better? I guess SEM doesnt need a hardner or anything and HEARD thats no bueno LOL :crazy::hmm::think: It will be sprayed out of a gun also. If i do multiple coats and sand in between can I cover up texture on lets say the column???
The quick gist of spraying the primer. Im not sure of SEM's product numbers off the top of my head. SEM makes a good product. With high build primer you wont be able to cover up anything less than a 80 grit sand paper and even then you might get shrinkage. I would sand everything down to 320grit. Now you can spray a high build let it dry over night to let the primer dry and not worry about shrinking. although some can be sanded an 1hr after spraying in the right conditions.Then sand with 600 and shoot color. You can spray primer/sealer which is just reduced primer,but make sure that the primer you are using is a primer/sealer. If you seal that parts then you can spray right over them with no sanding in between. Its called wet on wet. Make sure your not spraying at a high psi probably around 29 to 35. And when spraying sealer your looking to cover everything in one coat almost like spraying clear. Just dont run it or you will have to sand it

This is the primer I use. http://www.autobodybrands.com/primers/5424.html
 

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Discussion Starter · #15 ·
Thanks guys and thx for the link jimmybonez! I think I will stick to high build then! One last question can my lower valance be sprayed with sealer I know thats pretty flexible.....?
 
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