[Leakie]

I purchased an incomplete project that the PO started to paint, part of the car is complete other parts only primed. I am not a big fan of the color that was painted so I am going for a different color. What do I need to do to the completed part before painting? Do I just scuff it and reshoot the new color? It was painted with PPG single stage and I will be using the same type of paint just a darker color. Will I have a color matching problem by painting over one part that is color already and another part that is only primed? Thanks.

 

[hp246]

You not saying exactly what the project is, but if it was me, I'd like to know what is under the other guys work.

 

[swvalcon]

You shouldn't have a color match issue if the right amount of paint is applied. But myself I would sand and use a sealer for a nice base. Just a lot easier.

 

[Leakie]

You not saying exactly what the project is, but if it was me, I'd like to know what is under the other guys work.

I had thought about stripping it down, but the more I thought of it it did not seem necessary. The car was painted more than 10 years ago, and has just set since then. I think if there was going to be problems they would have shown by now? It is completely stripped down so you can see behind every panel and the job that was done was pretty good, not perfect, but probably as good or better than I can do. No I don't usually trust someone else's work but I think I will this time.

 

[Leakie]

You shouldn't have a color match issue if the right amount of paint is applied. But myself I would sand and use a sealer for a nice base. Just a lot easier.

When you say "sand" what do you mean? Scuff, block, wet sand...? The surface is in pretty darn good shape with the exception of one small scratch. I was wondering how far to go without getting carried away.

 

[69 widetrack]

hp246 is correct...It would be nice to know what's under the previous owners work ie. filler (to much, to deep, what kind), rust repair (how was it repaired, welded in patches or filled with filler or fiberglass)? So if your not sure of how it was repaired and prepared, you may be wise to take it down to metal to see for yourself...I'm not saying it was done wrong but, if you don't know, your better off to find out.

If your going to paint over top of the existing paint and primed parts, I would suggest you start off by blocking the paint and primer material that's on the car now. This will give you a good idea of how straight the car is, (the blue is fairly light in color and could hide waves in the finish, especially if your going to a darker color as a darker color will show more imperfections in the body work). I generally don't recommend sealer but, in this case a uniform coat of sealer would give you a consistent substrate color to ensure complete paint coverage.

You say your going to a darker shade of blue, is it a solid color or a metallic color? This does make a difference in the products you will be using, from sand paper to the type of paint. If the color is a solid blue (no metallic's) single stage is fine I would recommend blocking the car in 320 or 400 grit paper. If it's a metallic color, I would recommend using a base clear...(you never get the quality of shine that's desired in single stage metallic's). If you do go to base clear paint and your sealing the car, you can use the same grits for blocking as you would for single stage...if your not sealing the car, I would recommend you block the car in a 600 grit wet paper.

Hope this helps.

Ray

 

[Leakie]

Thanks 69 widetrack, like I said in the previous post the body work is pretty darn good, yes there are 3 areas that were patched(welded in) but you can see them from behind the panel and appear they were done by someone that knew what they were doing. There are small amounts of bondo that were used for smoothing but no globs anywhere.
The parts that were not painted, the ones the PO had primed and new parts that I got for the project I stripped to bare metal. The primer parts had set a long time (10+ years) and were starting to rust under the primer. They where then epoxied and then a high build primer. So all of the other parts are at the same point, just the 2 different surfaces between primer and paint.
I will be using a solid color, no metallics. If it is best to sand and prime the completed part I will do that, I was just wondering if that was really necessary.

 

[69 widetrack]

If your comfortable with previous work done and the car is straight, you wouldn't need to re-prime...you may want to seal the car before painting just to make your substrate one uniform color. This would help the new paint cover and ensure the same color all over the car. If you don't seal the car, just make sure you put enough paint on the car to cover the old existing shades on the car now. I would still recommend blocking the whole car before painting especially if your going to a darker color...as I mentioned in the previous post, a darker color will show more imperfections in the body than a lighter color.

Your going to be using a solid color so single stage is fine...just a bit of advice, it may be a good idea to put on an extra coat or two of paint. I suggest this because if in the future you want to color sand and polish the car, you'll have enough material and won't burn through as easily.

Ray

 

[Leakie]

Thanks again. I guess that is my biggest concern, the difference in colors. I don't want to get it out in the sun and see subtle differences between panels.
What do you mean by using a sealer? Are you talking just a straight 1 part sealer primer on everything or something else?

 

[69 widetrack]

Thanks again. I guess that is my biggest concern, the difference in colors. I don't want to get it out in the sun and see subtle differences between panels.
What do you mean by using a sealer? Are you talking just a straight 1 part sealer primer on everything or something else?

I would never recommend a 1K anything...they just don't stand up...Use a product that is catalyzed with and Isocyanate hardner...This product will out last any 1k product in both hold out (adhesion, sinking etc.) and durability. Sealer is generally referred to as a sealer/primer surfacer...What this means is the product acts like a primer but, doesn't need to be sanded. Allow the sealer proper flash time and apply your paint directly over top, giving you both mechanical and chemical adhesion, whereas primers need to cure and then sanded to achieve mechanical adhesion.

Hope this answers your questions if you have any more...please ask.

Ray

 

[Leakie]

Thanks Ray! Very helpful info.
I have no experience with a sealer so that helps alot. Could an epoxy primer be used as a sealer? The epoxy I used said it could be painted over without sanding after a certain flash time.
Thanks again for taking the time to educate the willing but unknowing!

 

[69 widetrack]

The willing and unknowing are a much better candidate for success than the knowing it all.

To answer your question regarding using your epoxy as a sealer...as long as the epoxy that your using is catalyzed, you should be fine. What brand of epoxy are you using?

Ray

 

[Leakie]

I used Nason epoxy.

 

[69 widetrack]

I have sprayed Nason 2K epoxy and painted directly over top with good results...I'm sure you'll be fine.

Ray

 

[swvalcon]

If the paint is good and your ok going over it just scuff sand good and feather out any chips and you should be fine. A lot depends on what you plan to do with the car. If its a long term keeper you may want to see whats under it. If your just going to clean it up and flip it sometimes you dont want to know whats under it.