This may seem a really dumb question to experienced sprayers but I'll ask anyway.I have high build cellulose primer for my car respray but am unsure of how much thinners to use.I have done a trial spray on a panel and find that the primer does not cover very minor blemishes in the prepared area.I understood that the high build would cover any VERY light scrathes from rubbing down etc,but wonder if I have over-thinned it.Any suggestions?
- Thread starter johnc
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malcolm
& Clementine the Cat
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About 50:50 paint to thinners is normally good for high build primer. You might see the scratches a little in the finish of the primer, but it should be thick enough that a couple of coats give you enough material to sand off without going through to whatever is behind it.
Chickenjohn
Morris Minor and Porsche 944 fan
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It depends on the primer. I have been using a very good yellow primer called (IIRC Goldseal beige) it is quite thick and needs more like 2/3 thinners, 1/3 primer. With celly primer, you need more than 2 coats. I would apply about 4-5 coats (or more) of cellulose high build primer. You will have covered the scratches then and have plenty of material for final sanding. On a black or dark coloured panel that is going to seen more prep before topcoat, i might even go 6-8 coats of high build cellulose primer. With the quick drying times between coats this is not too bad to do.
Yes, cellulose primer does need about 2x the coats of 2-pac but you can spray it at home with just a carbon filter mask without killing anyone and cellulose dries much faster. Last summer, I did some priming on a panel, let it dry, sanded it smooth and top coated it all in the same day!
By the way, have you sanded down to a fine enough grade?? I go at least to 240 grit before applying the primer.
Yes, cellulose primer does need about 2x the coats of 2-pac but you can spray it at home with just a carbon filter mask without killing anyone and cellulose dries much faster. Last summer, I did some priming on a panel, let it dry, sanded it smooth and top coated it all in the same day!
By the way, have you sanded down to a fine enough grade?? I go at least to 240 grit before applying the primer.
paintpot
Member
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High build primer going back to the 70/ 80;s usually 50/50 mix.less scratches in your filler less sinkage.Guide coat your primmer.Block with 320 .Put another guide coat on .Put a interface pad on your d/a with a 500 disc ,and then go over ,to take your 320 marks out.This will not take the shape out of your primer,only the 320 marks .
the snooper
getting older by the day
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as paintpot prime, let it dry, flat, and repeat that way you fill the scratches if you dont flat between coats you raise the level of everything you spray when all you really want to fill are the scratches
