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Spray Painted Surface Very Rough

I used cans of semi-gloss oil based spray paint to spray the finish coat on a book case. The surface was very smooth before I sprayed. But the sprayed surface was very rough after spraying. Seem like spray paint droplets might have combined together in mid air before landing on the surface. I used 400 grit sand paper to easily sand out the rough surface. Now the surface is flat instead of semi gloss after the sanding. My questions are:

  1. How should I prevent this problem from happening again?

  1. How should I put back the shine on the surface to something like semi gloss?

  2. How should I put a protective coating on the "flat" surface to allow me to clean the surface easily?

Thanks in advance for any info.

Jay Chan

Reply to
Jay Chan
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Sounds like you may have put the coat on too thin/dry.

Reply to
Leon

You are probably right. But the paint is coming from a can; I assume the manufacturer should have formulate the paint just right. Actually, I have used spray paint from cans many times before, and this is the first time I have encountered this problem. Does this have to do with spraying too close from the surface? Does this have to do with the fact that I sprayed into the inside space of the book case where the space is enclosed in five sides and the paint droplets might have bounced back and collided with each other and formed big droplets?

And what should I do to put the shine back onto the surface that has been sanded to a "flat" finish? Any idea? Thanks.

Jay Chan

Reply to
Jay Chan

You are probably right. But the paint is coming from a can; I assume the manufacturer should have formulate the paint just right. Actually, I have used spray paint from cans many times before, and this is the first time I have encountered this problem. Does this have to do with spraying too close from the surface? Does this have to do with the fact that I sprayed into the inside space of the book case where the space is enclosed in five sides and the paint droplets might have bounced back and collided with each other and formed big droplets?

And what should I do to put the shine back onto the surface that has been sanded to a "flat" finish? Any idea? Thanks.

Jay Chan

Reply to
Jay Chan

Clear coating with a wipe on poly should do the trick

Reply to
damian penney

Lots to learn hear but spraying from a can is pretty hard to get good results on anything large than toy car models unelss you are very careful and knowledgable.

  1. Yes, bounce is a likely culprit. But it could be too dry. This is a factor of the application method, not the paint mix only (see #2)

  1. The can formulation is a good general mixture but you need to apply it thick enough so it stays wet on the surface long enough to flatten and absorb any bounced material.

  2. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.

  1. This sounds like contradictory requirements and they are but they are the art of spraying. That is why the can is hard to perfect because with a professional spray system you can adjust amount of thinner, mix of air to liquid, pressure of air, pattern of spray, size of spray aperature, add driers, or extenders depending on humidity, temperature, etc, etc.

  2. Use a clear gloss spray over the top or use wax. Wax won't be as shiney and needs to be renewed. Also hard to reverse if you don't like the look so test first.

Reply to
SonomaProducts.com

Lots to learn hear but spraying from a can is pretty hard to get good results on anything large than toy car models unelss you are very careful and knowledgable.

  1. Yes, bounce is a likely culprit. But it could be too dry. This is a factor of the application method, not the paint mix only (see #2)

  1. The can formulation is a good general mixture but you need to apply it thick enough so it stays wet on the surface long enough to flatten and absorb any bounced material.

  2. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.

  1. This sounds like contradictory requirements and they are but they are the art of spraying. That is why the can is hard to perfect because with a professional spray system you can adjust amount of thinner, mix of air to liquid, pressure of air, pattern of spray, size of spray aperature, add driers, or extenders depending on humidity, temperature, etc, etc.

  2. Use a clear gloss spray over the top or use wax. Wax won't be as shiney and needs to be renewed. Also hard to reverse if you don't like the look so test first.

Reply to
SonomaProducts.com

Lots to learn hear but spraying from a can is pretty hard to get good results on anything large than toy car models unelss you are very careful and knowledgable.

  1. Yes, bounce is a likely culprit. But it could be too dry. This is a factor of the application method, not the paint mix only (see #2)

  1. The can formulation is a good general mixture but you need to apply it thick enough so it stays wet on the surface long enough to flatten and absorb any bounced material.

  2. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.

  1. This sounds like contradictory requirements and they are but they are the art of spraying. That is why the can is hard to perfect because with a professional spray system you can adjust amount of thinner, mix of air to liquid, pressure of air, pattern of spray, size of spray aperature, add driers, or extenders depending on humidity, temperature, etc, etc.

  2. Use a clear gloss spray over the top or use wax. Wax won't be as shiney and needs to be renewed. Also hard to reverse if you don't like the look so test first.

Reply to
SonomaProducts.com

Clear coating with a wipe on poly should do the trick

Reply to
damian penney

Clear coating with a wipe on poly should do the trick

Reply to
damian penney

It'll also yellow lighter colors if a non-yellowing formulation is not used.

One of the things I haven't seen mentioned yet is spray direction. Each successive pass should move INTO the overspray, this is typically away from the person painting. For example, the spraying will start at the edge closest for the first pass, moving left to right (or the reverse), with the last pass at the back edge. This allows the overspray to be covered with wet finish.

Reply to
B A R R Y

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

What is the source of the roughness? Paint fragments or small wood fibers that popped up from the surface?

You may well have "raised the grain"- caused such small fibers that remain after sanding to stand proud after getting wet.

Were that so, I'd be sure to use a cabinet scraper (rather than any sander) prior to sealing and between subsequent coats.

Can easily pass the "baby's bottom" test, doing that, with construction-grade plywood- utility stuff.

TTFN, J

Reply to
barry

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