ppg EHP painting problem.
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hi all,i m new to here.and i have a big trouble of spraying silver color on a hood.whatever i spent double care of controlling my gun,the paint job always comeout imperfection like blotch cloudy something like that…its not so terrible but it doent look good to me.the ppg EHP techbook shows always need drop coat(s) for even out the metallic,and on the hood or roof need two coat of drop coat.
but i try so many times and so many ways to paint a silver hood and with no luck…im feeling so disappoint of myself.
any help will be appreciate!!!!I’ve used that paint at a previous shop. It definitely needs the orientation coat/drop coat. What sort of gun are you using and what set up? I had really good luck with a Devilbiss Tekna, 1.3 tip and 7E7 air cap. I sprayed my colour coats @ 22-24 PSI and orientation coat @ 16-18 PSI. Add some distance for the control coat and lots of overlap, do not apply the base too wet, and allow it to fully dehydrate between coats.
Also, how much are you reducing the paint with the T494/T595? What is the temp/humidity in your spray booth?
Thanks for ur reply Ben. I have a sata 3000 wsb nozzle and iwata w400 with wb1.3tip. Sata using 29psi for cover 18psi for drop coat. Iwata using 20psi for cover 15for drop coat.and I use t494 to reduce 20% of the color.and I did add more distance to drop coat . Im getting worse Expecially the hot weather now .I m working in the high production shop, this problem is always kicking my ass.and can I ask how do u do a drop coat? When u spray how is the paint goes like?how wet or dry?If u can make a vedio its gonna be a big help lol
One more question I know tekna selling couple color are they different?
The base will be harder to control in hotter weather. Stop using the T494 and switch to the T595, see if that helps. You may also want to try reducing close to 30% instead of 20%. This may help as well.
I do the drop coat at a greater distance with at least 75% overlap (more overlap than a normal coat). Do not put it on wet. Probably on the dry side of medium. Someone on here, when referring to Sikkens, used the term “Sandy Beach” to describe what Sikkens wants. Similar idea with the PPG. Just be careful that the coat isn’t actually “dry” when you apply it.
Not to sure that you would be able to see the finish well in a video…
Sounds like you have some decent guns already. I did find the Tekna better than the 3000 with the 1.3wb tip. But you can still get great results with that gun.
Thanks ben again r u only spray one coat of dropcoat?yea I have many good gun I have paint car for 6years !but this……….
I drop coat on most colours was good. On finicky colours (golds, silvers etc) 2 drop coats on the horizontal parts does help, just make sure to follow those out into the adjacent panels.
Thanks for ur help!I will do more practice to make it perfect! :rock
One thing you could also try is using slow dry reducer and if its very hot like it is here near Chicago you can evan use very slow dry reducer. using your sata at low presure(18 or 20 psi) spray with your gun completely sideways. It may take a little practice if you havnt paint this way before but it gets the job done. I paint high end cars such as acuras, infinitis and lexus and have always had good results using this method. Hope this helps.
Thx shadow! Yes I always using 18-20psi for control coat! I have try to call the ppg paint rep to show me the way. But he’s so ridiculous to tell me just paint as normal.after, he told me it’s acceptable!!!I can’t even believe my ears and my eyes!also r u only spray side to side or doing cross way?
The blotchiness may be from not getting a good coverage over the sealer. Bleed thru. This is what my guy told me to do. Reduce everything to 30%, make sure your distance is 8″ away from the panel, over lap 70% on the ground coats. Reducing it will help it dry faster, also don’t wet your coats too much, takes longer to dry & will dry splotchy. Make sure you dry the coats @ least 5mins if your using the blowers. Control coat is 17-19 psi @ 90% overlap @ 12-14″ away from the panel, spray it fast, it should look semi dry with just a bit of blueish haze to it, if you spray your control coat to slow & to wet,all u did was put another ground coat on. & use your sungun before you control coat to check for cover & splotchiness. &
It’s really important tht u take your time to get used to it, your speed will pick up when you learn its quirks. Trust me it’s taken me a lil over 2 yrs to get, cause we have one booth, & r a production shop, so rushing everything hust made things worse.Also since I went up to 30% redution things have gotten better & faster. I use a sata 3k like you, it’s portent to be @ 27-29 psi on the ground coats this will help a whole lot, I also had to tighten down the fan spray to a smaller pattern, just seems to help with the over laps as well as the coverage. I tried the wide open didn’t like it, seemed like everything came out slpotchy.
Thx lild! I do use sun gun to check cover before put the control coat.and also I m agree with u about reduce 30% of the paint.it’s what Ben told me to do couple days ago! It’s work better and I found the metallic lay down better. The only thing I don’t know is how is the control coat looks like when the paint landed on the surface . I will try all ur tips,hope getting better! Thx avaunt lild!
Well like I said, it’s important to back off to 12-14″ on the control coat. It should look semi dry as you spray it. like paiinting the hood. As you do one side & get to the other side the first half should look dry. Plus when it looks uniformed semi flat look it’s done right. & make sure you do. 90% overlap & faster than your ground coats. Most of the time for me the blotchiness comes from the grouNd coats. & times the control coat fixed that, if it don’t I put another ground coat on. More or less it will take some practice. Not everyone I do comes out perfect.
Yes practice make perfect
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