DansYellow66

All was good in sanding out my painting project using PPG single stage black until I uncovered a thin area on my lower fender lip that it appears I failed to turn the gun around on each pass and hit, and I uncovered the sealer in color sanding.

It's not a big deal as far as using a detail gun or air brush to put 3 or 4 coats on but I've read about both DX840 Blending Solvent and D855 Fade Out Thinner for blending in and melting dry spray into the surface.

DX 840 is covered on the PPG Concept P sheet so I'll probably pick a pint of it up. The P sheet says to just lightly spray the blend in/overspray areas. I'm wondering if a light dusting on the thin coverage area first would help adhesion and blending???

Anyone with experience with this?

Thanks

Sanding away with finer and finer sandpaper in Arkansas

Dan

ragtopman

If you can clear the entire panel, do that instead of making the 'solvent blend' cause over time the blend edge will break down and then it will look like fido's butt.

But if you have to use the 840, such as on a sail panel and you have never done this before, run you a piece of tape across the panel, and use 1000g paper and lightly sand up to the piece of tape. You basically need a place to stop. Your first coat of clear will be on the repaired area staying away from the blend area, but on the second and last coat as your coming to that blend edge, you dont need a ton of clear on that edge, instead, your going to mix a little of your catalyzed clear with the 840 and melt it into that edge you created with the sand paper, blowing air on it will help it melt in and keep in mind, you cannot have any problems in that area. After its all cured run a buffer over it lightly and if you have done everything right, you wont be able to see the blend edge.

I am sure somebody else may chime in, and hopefully you can get it all fixed.

DansYellow66

It's single stage Black - no clear

ragtopman

same way, I have done solvent blends in the middle of doors and length's of hoods with single stage, I would definatly practice first making some blends before you try it on your project if this is new to you. Just remember, that blend edge is very delicate both in the buffing of the edge and what the UV rays will do to it.

DansYellow66

Fortunately it's down low on the side at the wheel lip. Can't believe I missed that area going around the car. I hope this 840 stuff works - I had to buy a gallon of it.

So, I can mix a little SS black with the DX 840 to spray around the edges?

markids77

Try what you want but I'd paint the entire section again... I know you had some issues with particulate matter in the surface, and it is still easily (sort of... you know what I mean) dealt with because there is nothing but the bare body to contend with. If you even think there is a weather window day, prep the entire nose, mask off the rest and lay a couple good wet coats on it. You'll be happier knowing there is a continuous, "monolithic" paint film as you continue the build.

DansYellow66

I'll try the blend first as I need to build up some paint film on the area anyway. If I'm not satisfied that will cut and buff out OK then I'll shoot another coat over the front from the rear of the door opening forward.

DansYellow66

Well, after further thought I decided this touch up and blend effort was about as much work and expense as putting another entire coat of black on the whole front end of the car. The paint store rep suggested forgetting the blending thinner (turned it in for more paint) and just do a good initial tack coat over the thin areas and look for any signs of lifting or wrinkling as it flashs off and if it flashed off OK, then apply another coat over the area and then come back over the entire front with a full coat of paint.

So, Markids77 - this plan should put me back in good standing again.

markids77

No insult intended I assure you! Blends have a tendency to "telegraph" over time and knowing how much time and effort you have in this so far I think you have made a better choice to recoat vs repair. Having re-read my reply I do wish I had been less "direct". My apology to you, Sir!

DansYellow66

No need. You were right on target. Thanks

Spraygun

Blending DCC is possible, I read using 840 ( blender ) and clearing the whole panel. Both will work, but I've had good luck mixing the two.
Blender is a reducer with a bit of UV protection, melts an edge but will chalk out eventually, clear has lots of UV protection but doesn't melt in real good. Before PPG came out with 840 we were taking RTC clear and mixing it 1 part to 6 parts reducer. Blends looked good but down the road they chalked. I will take RTS clear over reduced ( 10%ish) and mix it 50/50 with 840 to get the best of both worlds.
There are as many ways to melt in a single stage blend as there are painters, I came up with this mix repairing 40 foot buses with DCC and melting 4' wide blends.


S

DansYellow66

I gave up and went ahead and spot sealed the thin area and sprayed two more coats of black on the whole body. I don't have much paint left so I hope this is the end of it. I slightly over-reduced the last coat this time and it did come out looking nice and smooth and slicker this time.

DansYellow66

I finally moved the Cobra home from the warehouse paint booth where I painted it. It was great to finally get it out into some natural sunlight. It helped me see one small ripple and a couple areas of still light orange peel that I need to go back over and block a little more, but I'm pretty happy with it. I've only compounded it with a wool bonnet since color sanding. I still have a lot of buffing to do and I still have the door, trunk and hood jambs to buff out. I'm finally about to the point I can actually start assembling it.

Thanks for all the help and recommendations.

markids77

That looks truly excellent. If I might make a suggestion; I would wait to do the final polish until after you at least have it back on the frame, and all panels reattached and adjusted for gaps/fit. It is quite likely you will make some small blemishes/scratches guring panel fitment, and it hurts less if the finish is still "roughed in" versus mirror bright. Is that a MOPAR I see under the Vette in that garage?

DansYellow66

Thanks - I was kind of thinking the same thing on polishing. I think I need to make one more pass around it with the wool bonnet after I go back on a couple small areas and maybe go a round with the first foam pad (blue). Probably 99% of the sanding scratches are out but I see a few here and there. But then wait to do the other two levels of pad polishing (white and black) until later. Or maybe just stop for now after the wool pad.

Yes - that's my 67 GTX. It has a pretty pedestrian paint job on it. Good for cruise night. But when I get done with this I may go to work on it.

Keith Carlson

The little black Cobra is looking good!

929nitro

Lookin Sweet.