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Discussion Starter · #1 ·
91 mustang , sprayed SPI epoxy as a sealer . let it dry about 2 hours. Applied 3 coats PPG Shopline plus basecoat ( titanium frost ) light silver .

I have sprayed a few metallics in the past . Med . coat, cross hatched 2nd coat. Immediately After last coat increased pressure a little , increased distance a little to fog ( even out metallics ) . Didnt dry spray it.

Temp in garage about 72-75. used DT870 med. reducer. Everything went well.

Let that dry 20 hrs , temp probably dropped to 55-60 in garage overnight.
Problem : Today I sprayed SPI Universal clear , I sprayed it wet like normal. I have a few mottling places on the hood, hatch and roof. None on the sides.

I called a friend of mine who owns a restoration shop, been painting 25 years. He said its possible the clear was put on so wet it moved ( shifted the metallics ) . He had a similar problem on a light silver last year .
His solution, let it dry for a couple of days.

Grey scotchbrite it, clean with wax and grease remover , apply more basecoat. Put 1st coat of clear on med. not wet . 2nd coat med. 3rd coat wet . He said this worked for him. If I had used a hardener in my basecoat would this have helped?

Any thoughts appreciated.
 

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Silver is THE hardest color to paint....I've seen pros have fits over it ...Thats when I get a phone call to come over and check it out....The cause has ALWAYS been from the base coat... motteling and striping are in the base from application...pick another color or have a pro's pro come over to base it. Sorry thats the best I can tell ya ...Other than try again....try this ,its how I do it.....Three coats of base,all applied the same way.Criss cross pattern gun held 12-24" from the surface,a little higher pressure,one side of theX pattern is one coat ,the other side is another coat....look into the paint past the color into the metalics look at the metalics closely ,all over the car,repeat as many times as you have to ....It takes a trained eye and years of experiance to trigger the gun .You might get lucky with Chroma base or another brand.....They are much more forgiving....I hope this helps....If you must do it on your own PM me for a more detailed explaination of the whole process,A-Z....But still...thats no garuntee you'll get it right , mabee right enough though...
 

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Discussion Starter · #4 ·
I agree silver can be difficult, Have sprayed it a few times.
This probably my 3rd complete car ( silver ). Sprayed many piece parts silver bumper covers etc. I looked real well ( a few times), after applying base.
Went back probably 3 times within the 20 hrs and looked. Never had this problem with what I believe is the clear moving ( shifting the metallics)

I used a med. reducer and think it dried to quick and left alot of over spray dust , and the clear moved it ?? Could be wrong.

It was only in 2 -3 spots about 3 inches in diameter on the hood and hatch.
Sides looked fine.

I have now let it sit 2 days, have sanded dust nibs with 600 wet. used grey scothbrite. Ready to blow off real good, maybe wipe down with waterborne wax and grease remover ? Or solvent based ? Any advice appreciated.
 

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Discussion Starter · #6 ·
SPI Universal clear , Thought about just doing those panels but was concerned it might not match ? So I plan on baseing the whole car again, just one or two coats. Watching it closely as I go.

I never tack the last coat but have used a white / non sanding scotchbrite pad to lightly touch a dust nib that wouldnt break loose with air.

Never done a lot of blends , If I had decided to do just those panels , How should I have done it ??

Thanks for your help.
 

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SPI is what I use so your good there ,its not a problem with that...You cant touch that last coat at all,with anything, you'll distort the metalics....you only have two coats of clear on it .right?Wheres the bad spots and how many? Blending is the only way to be sure to get a good match ,if you redo the whole car the same thing could happen in another spot or spots or worse ...how much base do you have left? how much have you used? will you have enough to do the whole car again theres a lot of questions that need to be answerd but I'm pretty sure you should blend for cost , quality and time....you can always pm me for a call, it might be easier....
 

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Discussion Starter · #8 ·
I see what your saying , so the sides ( fenders, doors, quarters and possibly the roof look ok ) no need to apply base to those areas ? I have two coats of clear on it. Could mess those areas up by rebaseing , Since those panels look good and the metallics are locked into place with clear , just reclear them after I get the base right on the troubles areas ??

Few areas on hood and back hatch . I do have more base , maybe pint and a half. I was planning on getting another quart $ 58.00 tomorrow , have them add it to the other . I have about 28 4ft flourescent bulbs overhead , and have looked at the sides with a 500 watt halogen from a distance and different angles .
 

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Something everyone should know....When buying paint .....the smaller the quantity ,the more it wont match....after spraying a car with a gallon of paint,redoing a panel with the leftover paint doesnt necessarily mean it'll match...always stir it up very well at the beginning when you first open the gallon and you'll haveless trouble if you need a redo.learn to blend... its important to success
 

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You need to invest in an infrared thermometer.
55-60 is WAY to cold to be sprayig Universal,or ANY clear for that matter.
I'm going to agree with your friend,the clear reweted the base.Top sides are ALWAYS wetter than sides,and,you have NO idea WHAT the METAL temp was when you sprayed the clear.
70 is about as "low" as you want really and with 870 in the base,it slowed down as the night progressed.
When shooting in cooler temps,the FIRST question Barry will ask is "What was the METAL TEMP?"
Get a thermometer and check the metal temp BEFORE spraying ANYTHING.
I been burnt before too and "playing" around with reducers in cold weather is the norm with base but clear is another story. You only have a select set of activator temps and you best abide by them or be prepaired to deal with the concquenses.
I also have to agree with DB on the paint, Chances of getting 2 of the SAME mix's are next to impossiable.Size be damned.The HUMAN factor is involved and trying to respray with a new can is a gamble even mixed in with the old.
I always have my jobber mix at least an additional qt on completes and mix it in with the total,then mix,divide into qt cans and spray from them on metallics or custom colors.Then, I at least have a good chance of matching.
And yeah, Blending is ALWAYS the "option" but my chances are a LOT better too.
 

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Discussion Starter · #13 ·
I wetsanded the dust nibs with 600 grit using very little water, as not to disturb paper,tape etc.

Scotchbrited grey the rest. Blew the car off , wiped carefully with waterborne solvent. Let that dry, blew it off again. Used tack rag.

Applied 2 coats of base with a slow reducer. Temp was 72. It layed down nice, no dust overspray like I had the 1st time.Metallics were even, no mottling etc.

Never thought about using this slow of reducer in this temp 1st time.Let this dry about 3 hours then applied 1st of clear lightly, let it flash. 2nd coat a little wet, 3rd wet,4th wet.

Only problem two little bugs landed in hood of all places on 2nd coat. I used a dirt pic ( looks like a bugs sword )
to remove most of them, some small specks might be left.
Of course this didnt happen the 1st time spraying , always something to contend with I guess.

I think it will be fine after wet sand and buff. Thanks for everyones help, I never stop learning.
 
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