Painting issue

L

LHolderman

Member
I base coated and clear coated my Murray body this week. I have an area above the rear window that I believe is clear that is now rough. I waited my times between coats and when I was doing the clear I noticed that sunlight was beating down in that area. I think it was too hot for the clear as the rest of the car looks fine and it wasn't in sunlight. Is there anyway to correct this issue?? Or do I sand the car down with something and shoot color and clear again. Not a good week...

Larry Holderman
Warsaw, IN
 
You can just re-clear the section that is "rough". Mask off the rest of the car except for the section in question. Wet sand the rough section in question progressively with 800 and 1000 grit. Sand only until you've created a smooth surface. Be gentle and if you start to see color in what you're sanding off, stop sanding. You don't want to sand off the color or you'll create more problems. Then re-clear the section.

Wait for your first attempt to dry well ---- I would say at least a week. As you decide where to set the boundary for your sanded/masked area, mask it in a such a fashion that you minimize the areas that will need to be cut/polished once you've finished your second clear. Most body shops call the process of clearing over clear "flow coating". Learn more by researching flow coating.
 
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Depending on the number of coats of clear you should be able to color sand and buff it out.
 
I have two coats of clear on the car. I own a buffer and supplies but have never used or seen one used (correctly). Both ideas sound better than doing the entire car over...
 
bruceincam said:
You can just re-clear the section that is "rough". Mask off the rest of the car except for the section in question. Wet sand the rough section in question progressively with 800 and 1000 grit. Sand only until you've created a smooth surface. Be gentle and if you start to see color in what you're sanding off, stop sanding. You don't want to sand off the color or you'll create more problems. Then re-clear the section.

Wait for your first attempt to dry well ---- I would say at least a week. As you decide where to set the boundary for your sanded/masked area, mask it in a such a fashion that you minimize the areas that will need to be cut/polished once you've finished your second clear. Most body shops call the process of clearing over clear "flow coating". Learn more by researching flow coating.
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I rarely use clear on projects in my shop just for the reason Larry has experienced. My experience has always been that you cannot blend-in Clear like you can a single-stage paint because it will always leave a hazy ring around the edge where the new Clear has been feathered in. I have always found the entire panel will need to be re-coated (-flow coated) to have a breakpoint to hide the edge of the new Clear. Bruce, by you suggesting just recoat the rough area, is your experiences different than mine on the ring forming on spotting a panel?
 
BRENT in 10-uh-C said:
I rarely use clear on projects in my shop just for the reason Larry has experienced. My experience has always been that you cannot blend-in Clear like you can a single-stage paint because it will always leave a hazy ring around the edge where the new Clear has been feathered in. I have always found the entire panel will need to be re-coated (-flow coated) to have a breakpoint to hide the edge of the new Clear. Bruce, by you suggesting just recoat the rough area, is your experiences different than mine on the ring forming on spotting a panel?
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Well, yes and no. In general, I can recoat a small section and then cut/buff out the overspray. But, it's tedious to do so but, ---- in most cases less work than respraying the whole project. The more you spray, the more chances you create to introduce problems. I agree that whenever possible you should mask up to a "hard edge" ---- window, door frame, panel edge, hard body contour ---- whatever you have that makes sense. The best result will be masking up to that hard edge and then spraying up to that edge from the other side. Then just remove your mask and you're done. But sometimes you can't avoid crossing a panel. When you do, you never want to spray up to that hard tape edge ---- that's going to be hard to get out. Your hard tape edge should be several inches beyond your spray edge ---- you'll leave an area that needs to be cut/buffed. Make it as small as possible. There are also chemical blenders available ---- I've never used them so can't comment. But as I understand, they also require cutting and buffing to finish.
 
I have checked out the video link and it gives me some good info. I will have a problem terminating the correction area as it is above the rear window. But like it was stated I have nothing to loose.

If I am not happy with the results and want to wet sand the clear coat to where I can apply paint again. What grit should I use??
 
LHolderman said:
I have checked out the video link and it gives me some good info. I will have a problem terminating the correction area as it is above the rear window. But like it was stated I have nothing to loose.

If I am not happy with the results and want to wet sand the clear coat to where I can apply paint again. What grit should I use??
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I would use 800 grit, -but 600 will work. My reason is I don't want to see scratches in my base.
 
this is one reason i only use single stage at home in my shop its one stop shopping. you paint the car and its done.
-in a home shop (i don't have a booth) there is no worry of bugs and dust landing on the base. i do get stuff in the paint but it is easy to wet sand and polish. non metallic paints.
-anything you do to the base before you clear will show and be magnified by the clear. (if you have to sand a mistake the tiny sand scratches will look like the grand canyon)
-single stage will last for years (many will say it doesn't but i have a canoe i painted years ago, in automotive urethane , its left outside year round and it is still like the day i painted it)
-runs can be wet sanded and polished, (non metallic colors)
-as far as a panel repair, i think with both 2 stage or single stage the whole panel will have to be refinished, blending like was done in the old days with lacquer is long gone.
-no urethane in 1928 but they were single stage solid colors.

only my opinion, this works for me and i have had years of success.
 
LHolderman said:
...... when I was doing the clear I noticed that sunlight was beating down in that area. I think it was too hot for the clear as the rest of the car looks fine and it wasn't in sunlight......
Larry Holderman
Warsaw, IN
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Getting back to the root of the problem, painting in sunlight will cause the paint to start drying even before it hits the panel and never has a chance to flow. Tiny beads of paint will dry and stick to each other like a hail storm. You will not get it smooth without sanding it down. Even just small spots of sunlight will turn out that way.


In the 50's my first paint job on a 46 Hudson was primer only and painted outside in the sun. The owner could scrape the skin off his hand when he checked the smoothness. He was not happy and I didn't have a clue.
 
I used to put thinner/reducer in a spot gun and turn the flow needle down to low output. I would wait for a bit after noting a dry spot then spray a super light coat of reducer over the dry spot. wait another 15 minutes or so then do it again. Repeat this if necessary. This will level out a dry spot and make it easier to polish out but it always depends on what material or paint a person is shooting on there. A person has to keep the reducer gun ready so that this stuff can be done right after shooting the final coat. I generally only have to do this when something happens during the paint shoot that causes a problem. No matter how much a person tries to get things perfect, sh!t happens now and then.

I'm not a fan of clear coat but it has it's place. I mostly use single stage polyurethane if I can get it. Some paints need to set up for quite a while before color sanding. If it can't be repaired by polishing then mask off the panel to its nearest edges and cover the rest of the project & reshoot it. Cars with lots of seam lines make this a lot easier. Most of my experience is on the helicopters and they have seams all over the place but shooting over a thousand rivets is a PITA. Paint likes to sag around rivet heads.
 
After looking over my recent paint job, I found more dry areas than I wanted to try to buff out. So, I have started the wet sanding as Brent stated. I few areas I had to use 400 grit and then worked up to the 800 grit as it was too rough for the 800grit. I have a good 8 hours of sanding and will give it a good wash job tomorrow and see what it looks like. One good thing was that I didn't have any bugs in the paint and that's a first for me. Why is it that when it comes to sanding all your help is busy???
 
I would use finesse it with a foam pad . It has been sanded a lot and traditional rubbing compound is pretty aggressive. Even the fine stuff. If you are not careful you could burn through what’s left of the clear.
 
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I have a 20+ year old paint job on my streetrod (36 Plymouth) that still looks nice. I'd like to clear coat it, but this is just the reason why I keep telling myself to leave well enough alone.
 
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