Problems with base coat PPG

General Discussion. Make yourself at home...read, ask and answer!

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PostPosted: Sat Jan 21, 2023 7:03 pm
gunder463 wrote:I cant even figure out how to post a picture.


While typing your post or reply, scroll down to the Upload Attachments Tab and select it.
Click on the Choose File tab and browse to the picture on your computer.
Select the picture you want and the click the Open button on the lower right side of that page.
This will put the file in the box next to Choose File.
Next click Add the file and wait until your cursor jumps back up to this text box.
Select where in the text box you want the picture to appear, then scroll down and you will see your file with the option to Place In Line.

Click Preview to see how things look and if happy hit the Submit button.
1968 Coronet R/T


ACTS 16:31



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PostPosted: Sun Jan 22, 2023 8:18 am
JCCLARK wrote:Too cover a sand through, base coat has to be put on with
very light coats and plenty of flash time in between.
To put it on heavy enough to run is way to much
at one time.

Yep, I used Omni with the same gun and tip, GPG with 1.3, and was amazed at how smooth and consistent it came out. I’m going to post a picture if it, it really looks better than I imagined possible. ( thanks to all the help from this forum). Looked like it had been buffed. Only problem I had was with about 5 runs that were due to my lack of experience. And it being single stage which is prone to running. I should have considered the fairly cool temp—- 70— and given it a few more minutes between the 2 coats. And maybe used a tad less reducer. I had the medium temp reducer. I also used Automotive wax and grease remover.
Next time you sand a run, look at the youtub vids on it. I haven’t attempted it yet, but they say use a new razor blade on the high parts, then glue some 320 sandpaper to little blocks of plywood, like 2” square, sand with that then on down with finer and finer paper then buff then polish with variable speed rotary tool, going slow and careful. It ran because it had too much paint, so as long as you are careful it should work out



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PostPosted: Sun Jan 22, 2023 12:27 pm
at 70* you should have been right in the sweet spot of your mid temp reducer, maybe just a tad slow but thats good. it lets it atomize better and flash just a little slower, this makes it flow out better. you just have to slow down, a little more time between coats. don't try the lesser reducer, that will cause more problems. a higher viscosity won't atomize good, you'll have to apply it wetter to get it to flow out good. then its to heavy and down on the floor it goes. more reducer is actually better than less reducer.
Jay D.
they say my name is Jay

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PostPosted: Sun Jan 22, 2023 3:30 pm
Bustedwrench wrote: . . . Next time you sand a run, look at the youtub vids on it. I haven’t attempted it yet, but they say use a new razor blade on the high parts, then glue some 320 sandpaper to little blocks of plywood, like 2” square, sand with that then on down with finer and finer paper then buff then polish with variable speed rotary tool, going slow and careful. It ran because it had too much paint, so as long as you are careful it should work out


You have to be extremely careful using a razor blade. A fresh run will often pull the clear under it out leaving a gouge all the way to the base coat. The other concern is the edges of the razor blade cutting into the surrounding clear.

Some advocate for bending the razor blade in the center so the edges are up.

I find the block of wood and sand paper method the safest. You do need to exercise great care to keep the block of wood parallel to the surface and just sand the run.
When it's almost flush, switch to 1000 grit, then 1500 and fishing leveling with the surface with 2000.
1968 Coronet R/T


ACTS 16:31
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