Spray Painted Surface Very Rough

Page 1 of 2  
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?
2. How should I put back the shine on the surface to something like semi gloss?
3. 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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Sounds like you may have put the coat on too thin/dry.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Clear coating with a wipe on poly should do the trick
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This sounds promising. I have a can of wipe-on-poly left over from a dinner table project. I will try it on an area of the book case that no one sees, and I will find out if I like the effect.
Thanks.
Jay Chan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

This sounds promising. I have a can of wipe-on-poly left over from a dinner table project. I will try it on an area of the book case that no one sees, and I will find out if I like the effect.
Thanks.
Jay Chan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I tried that last night, and I like it. I will use it all over the book case tomorrow. Thanks for the great tip.
Jay Chan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
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)
2. 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.
3. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.
4. 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.
5. 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.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
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)
2. 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.
3. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.
4. 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.
5. 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.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
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)
2. 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.
3. Howevr, you don't want it so wet that it runs or is so thick it doesn't dry well.
4. 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.
5. 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.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Clear coating with a wipe on poly should do the trick
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
damian penney wrote:

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.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Clear coating with a wipe on poly should do the trick
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Bingo
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@sme-online.com wrote:
I wish you google-groups posters would migrate to a decent news reader - then we wouldn't get these replicated posts.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Google Groups wasn't working right yesterday, after posting it would say there was an error posting the message (hence folk hitting submit multiple times)
This is the first issue I've had with it and overall it makes for a good interface to usenet.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On May 23, 2:49 pm, snipped-for-privacy@sme-online.com wrote:

The roughness was definitely from the spray paint, not from raised wood fibers. The roughness from raised wood fibers would have taken me a long time to sand them away. On the other hand, sanding out the roughness from spray paint was quite easy (the only downside was that sanding also removed the shine from the paint, and I will fix this by using wipe-on-poly).
I have put multiple coats of oil based primer over the surface; therefore, I don't have the raised wood fibers issue any more. Moreover, the spray paint is also oil based.
Thanks for pointing out the possible cause of the roughness though.
Jay Chan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.