Any tips on PPG base coat application? [Archive] - Team Camaro Tech

: Any tips on PPG base coat application?


joe clance
Jan 2nd, 03, 02:40 PM
In process of spraying front cap of 69 camaro. Using A HVPL gun and PPG base coat clear coat. Does anyone have helpful words of advice for base/clear coat application of ppg duracrylic DDL metallic base coat. What ive been experiencing is an orange peel effect when applying loght coats and what appears as color strips when applying heavy coats. While heavy coats minimize the Orange peel effect, the color striping in the too heavy areas are real hard to minimize. Need helpful advice before continuing to the clear coat process.

thx for any advice
joe c

BBCamaro
Jan 2nd, 03, 03:13 PM
hey, what size tip are you spraying with??? it should be a 1.3 or 1.4 for best results with base/clear. also on the base, just make it an even coat, not heavy, but not too light(a medium coat), if you like after the second coat of base coat i like to mist the panel that i just finished to help even all the metallic or pearl in the base coat i have had good luck doing this, now for the clear lay 2-3 medium coats down, and allow 20-30 minutes in between, its better to be dryer than tacky, you want to be able to touch clear(in unseen spot) and when you pull finger off no stringy's come with it, you just leave a faint little mark, if you don't have laytex glove on you should see a light finger print, now its ready for the 2nd coat or whatever coat you are on. just spray and slow down to the point you can see it lay on with minimal orange peel, if the gun is set-up you won't have any runs and a nice job. now also what pressure are you spraying with??? hvlp you should be spraying somewhere around 20 psi, if you are running lower this could be your problem with peel, anyways let me know
Jake

joe clance
Jan 2nd, 03, 05:53 PM
1.3 mm tip. Spraying at 30 PSI. I noticed that more paint = less orange peel. But the paint will leave a stripe that is darker than the rest of the panel. I already have three coats and ended up backing off the paint to rid the panel of the stripes. But have orange peal. I cant sand the paint so i'm trying to finish the base w/ the best finish. I'm thinking i'll "dust the panels" as you suggest and color sand the clear coat after the second clear coat? Any thoughts?
thanks
joe c

oramac 68
Jan 2nd, 03, 05:58 PM
joe, it sounds like the spray tip is partilly or fully clogged on i side of the pattern, try soaking and cleaning it out

djunod
Jan 2nd, 03, 06:07 PM
My Dupont instructor had me spray vertical passes and then mist horizontally to get rid of the horizontal stripes that I had made (from not overlapping properly).

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David
Camaro - '68 327 Coupe (http://www.makoshark2.com/cars/68camaro), '86 Z-28 IROC (http://www.makoshark2.com/cars/86camaro), '89 IROC-Z (http://www.makoshark2.com/cars/89camaro)
Corvette - '73 Mako Shark II (http://www.makoshark2.com/cars/73corvette), '82 Cross-fire (http://www.makoshark2.com/cars/82corvette), '01 Coupe (http://www.makoshark2.com/cars/01corvette), Casual Corvettes (http://casualcorvettes.homestead.com/CasualCorvettes.html)

[This message has been edited by djunod (edited 01-02-2003).]

joe clance
Jan 2nd, 03, 06:07 PM
BBCamaro, you got pictures. your thoughts?
thanks
joe c

joe clance
Jan 2nd, 03, 06:12 PM
Oramac, i'm soaking the gun overnight. I'll give it a good inspection and cleaning before i hit it again. let you know how it goes. It seems this a real touchy feely process!

thanks
' joe c

djunod
Jan 2nd, 03, 06:36 PM
Is it good to soak the whole gun overnight? My SATAJet & Walcom manuals both instruct never to do that...

You should disassemble it and clean it properly.

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David
Camaro - '68 327 Coupe (http://www.makoshark2.com/cars/68camaro), '86 Z-28 IROC (http://www.makoshark2.com/cars/86camaro), '89 IROC-Z (http://www.makoshark2.com/cars/89camaro)
Corvette - '73 Mako Shark II (http://www.makoshark2.com/cars/73corvette), '82 Cross-fire (http://www.makoshark2.com/cars/82corvette), '01 Coupe (http://www.makoshark2.com/cars/01corvette), Casual Corvettes (http://casualcorvettes.homestead.com/CasualCorvettes.html)

Toby Keen
Jan 3rd, 03, 01:32 AM
Is the 30 PSI entering the gun or leaving it? If it is the entering pressure, it's too low and could result in metalic "stripes". You could also back off on the material (amount of paint delivered by the gun) a little but it sounds like a dirty gun to me.

BBCamaro
Jan 3rd, 03, 02:04 PM
hey, for sure soak over night, also and 30 psi entering should be more than enough for a hvlp, might try lowering it to 20-25psi, most hvlp want 8-12 psi at the tip, and the only way to check that is to have a special tip that has a pressure gauge on it and it is pricey, i would use right around the max inlet pressure the gun calls for, wheni first started i had a cheaper craftsman(devilbiss parts)150 bucks and it said 23 psi max inlet i spray with right around there and have great results but i moved on to a sata rp jet a few years ago and will never use anything but unless it is spraying primer or spray mask!!oh ya i spray with 32 psi in my sata rp(reduced pressure, not quit hvlp but less pressure than conventional) and have better than factory results, very very little orange peel
Jake
let me know
Jake

[This message has been edited by BBCamaro (edited 01-03-2003).]