paint job repair

[watermelonman]

I have gotten fairly good at repairing rockets. However at the end of the process I want to patch up the paint job, too. I have pieced together a reasonably effective process of taping off the unaffected areas with blue tape, sanding lightly, possibly priming, then finishing the paint as usual.

It is not perfect, though. When I sand to a taped edge, I get dust buildup on that edge, which can get painted over and come out poorly. Pulling up the tape means imperfect lines when putting it back down. So I thought about sanding only the directly affected area, but that means I will be painting over clear for the rest of the untaped area.

How well does painting over clear work, or what other techniques work well for paint job repair?

 

[taiwanluthiers]

It depends on the paint...

If it's lacquer based it's easy (though I will assume it's not). Brush over the dinged area to repair the color. Build up the paint over time to get it to the right thickness. Then sand it flat and polish it with a polishing compound. You must however wait at least 2 weeks for the paint to cure properly. The repair should be invisible assuming the color was properly matched.

If you're repairing enamel it's a little complicated because you can run into incompatibilities...

For 2K automotive lacquer, I use CA glue to fill the imperfection and then buff them out. It won't be totally invisible but will be pretty hard to spot. I've repaired a few guitars this way...

 

[scsager]

I'm not understanding why you put the tape on before you sand the affected area.

I use tape to cover areas where I don't want PAINT overspray. I don't put tape on a rocket I'm sanding.

 

[Nathan]

Here's how I do it:

https://www.rocketryforum.com/showthread.php?62382-Repairing-cardboard-tube-damage

This did not have clearcoat before the repair but yes, you can paint over clearcoat. If the original clearcoat was enamel you must use enamel. If the original clearcoat was lacquer then you can use either lacquer or enamel.

 

[Micromeister]

I'm not understanding why you put the tape on before you sand the affected area.

I use tape to cover areas where I don't want PAINT overspray. I don't put tape on a rocket I'm sanding.

Taping good paint areas is done all the time. It helps prevent sand "Feathering" of already good painted surfaces and give a straight easy to see division line between the area to be repaired and the original good surface. After sanding the damage sanded tape is replaced with another piece to aid in overspray prevention. Once the repair is painted the tape is removed and any "Paint Dam" line is easily removed with fine wet sanding or use of Finessit-II.

 

[watermelonman]

I'm not understanding why you put the tape on before you sand the affected area.

I use tape to cover areas where I don't want PAINT overspray. I don't put tape on a rocket I'm sanding.

Because I wanted to avoid painting over clear coat. If I sand to remove clear coat, then paint, with the same tape line, painting over clear would be avoided.

It sounds like that is not a big concern to others, so I think I will try without in the future. Painting over clear was the crux of the repair job.

 

[hball55]

Here's how I do it:

https://www.rocketryforum.com/showthread.php?62382-Repairing-cardboard-tube-damage

This did not have clearcoat before the repair but yes, you can paint over clearcoat. If the original clearcoat was enamel you must use enamel. If the original clearcoat was lacquer then you can use either lacquer or enamel.

Try Nathan's way. From the paint jobs he's shown in this forum, I'd say he's a master at it.

 

[AfterBurners]

I have gotten fairly good at repairing rockets. However at the end of the process I want to patch up the paint job, too. I have pieced together a reasonably effective process of taping off the unaffected areas with blue tape, sanding lightly, possibly priming, then finishing the paint as usual.

It is not perfect, though. When I sand to a taped edge, I get dust buildup on that edge, which can get painted over and come out poorly. Pulling up the tape means imperfect lines when putting it back down. So I thought about sanding only the directly affected area, but that means I will be painting over clear for the rest of the untaped area.

How well does painting over clear work, or what other techniques work well for paint job repair?

Take pictures after you finish building before launching and save them...over the years I learned that scratches and chips are all apart of the rockets personality...as long as its safe to fly

 

[K'Tesh]

Try Nathan's way. From the paint jobs he's shown in this forum, I'd say he's a master at it.

+1

 

[watermelonman]

Take pictures after you finish building before launching and save them...over the years I learned that scratches and chips are all apart of the rockets personality...as long as its safe to fly

Hah, absolutely! I do not normally bother repairing paint but for drogue landings and a few other problems that take big chunks off, I like to touch it up a bit. For example my Nike Smoke lawn dart caused enough compression of the tubing that large pieces of paint simply fell away -
[video=vimeo;145757242]https://vimeo.com/145757242[/video]

 

[watermelonman]

Here's how I do it:

https://www.rocketryforum.com/showthread.php?62382-Repairing-cardboard-tube-damage

This did not have clearcoat before the repair but yes, you can paint over clearcoat. If the original clearcoat was enamel you must use enamel. If the original clearcoat was lacquer then you can use either lacquer or enamel.

Holy smokes, I cannot believe that was without clear coat. I suppose the polish and wax are the same idea but it looks like you are getting far better results with that than I am getting with clear coat.

Thanks for sharing, and nice rocket!

 

[taiwanluthiers]

Fender made several guitars without clear coat, still same shiny finish. The reason they used clear coat was economics. Clear coat was a lot cheaper than color but sometimes when they were in a rush they sprayed on thick layers of clear and polished that instead of clear coating. That step saved time but you could tell when they don't yellow as much as ones with clear.