A 'professional' powder coater who will remain nameless for his own protection (although he certainly doesn't deserve it) not only had my parts for well over a year but also failed to ceramic tint clear coat them as he said he could. So he powder coated them black but did not mask them or plug the holes properly. I am not sending the parts back again so how do I best clean up the overspray on the polished aluminum surfaces which were specifically polished for appearance? Is there a solvent I can use such as MEK or aircraft stripper? Any professionals on here who can point me in the right direction? Thanks guys....
Damn! I run a powdercoating line... damn, damn! We send our paint hooks and fixtures out to be thermally cleaned when they get too built up with powder (burned) Got any pics? Hard to really imagine what you are dealing with without seeing it.
We had a frame powdercoated last year. When we were ***embling it we got brake cleaner on the powder coat. It ate up the coating and made it soft enough that you could peel it with a fingernail. This was maybe 2 weeks after the coat job. I thought this **** was tuff. Give it a try.
There are many different types of powder. (epoxy, urethanes, tgic polyester etc..) If it's TGIC or something similar it's going to be prety tough.
mek works, any solvent and a rag and some elbow grease, If he did the threaded holes too, those will all have to be chased with a clean tap.
Okay, here are some photos of these ahem - throttle bodies. They were polished but then I changed my mind as there was no contrast with the polished intake - just a sea of polished aluminum. So I took them to this business who had been showing their stuff at the GNRS where the owner ***ured me he could ceramic color tint them a translucent black to look like black nickel. After several months he told me he had tried three times but it did not look good, so he powder coated them black and told me they looked terrific. When I got them back this is what I received. I sent them back for clean up and waited and waited and waited. I called many times but got the usual runaround. Eventually after another eight months I called up and told them to send the parts back. They were delivered originally in February 2010 and finally arrived back for the last time in July 2011. The pockets for the injectors are a mess, the top area is meant to be high polish but the protruding bracket for the fuel rails is meant to be completely clean for an interference fit. The injector pockets have peeling, lifting and flaking powder coat and are meant to be free and clear. The air bleed holes are plugged up and all mount holes and threads have powder coat on them. The holes where the nuts hold the throttle bodies to the intake are meant to be devoid of powder coat as it will wrinkle when the nuts are torqued down on the intake studs. Anyway here are the pix of a 'professional' powder coating job on high dollar components....
Wow, thats pretty sloppy work, you might have to cut the coating back on the injector port, and try to touch it up some way once the injector is in? idk , its a bone thing they did to you Looks like a ton of work just landed in your lap
You have a bigger problem than trying to clean up a little overspray. Powder Coat is not much different than paint in that there are many different types of resin systems that will be durable in different ways (chemical resistance versus uv resistance for example). A good lesson here. Any body shop or powder coater worth their salt should be willing to provide a sample panel to sign off on before proceeding with the real thing. This is to verify color, smoothness, translucency, etc. I have seen way too many things screwed up by shops that think they know what they are doing and have NO IDEA. I have a buddy with a car that was painted with $2,000 worth of HOK translucent black over metallic red. It was supposed to look like Brandywine, but it just looks black and is streaky with red marks here and there. Total incompetency. The next step should be some agreement regarding the expected quality prior to any payment being made. And of course lastly, don't pick up parts and pay for them unless they are acceptable. This basically shows acceptance and will make it difficult to get anything done beyond. Obviously you know all that. Not trying to state the obvious, but these kinds of deals really make me mad. Obviously your applicator should make this right. Not sure what that will be, but I think I would see if the parts can be stripped 100%, repolished and get my money back. Good luck!
I haven't had luck with chemicals but I haven't tried a whole lot either (i can say brake cleaner and EZ off do very little if anything). taps, drill bits, reamers and counter sinks for holes. for small surface areas though, the single best thing that I've found is a little dremel wheel #425. does a great job removing powder but not damaging the metal underneath (at least with steel). Available anywhere dremel is sold and they last a surprisingly long time, in my opinion. Can't remember using it on aluminum, so I'm not sure how it would treat aluminum. It will be dusty though.
Having been in the powder business for many years, this is what it appears to have happened....the green residue is from the hi-temp tape used in the shops to mask off the required surfaces; from the shot of the mount it appears that rather than mask each surface individually, one larger, wider tape was folded over, resulting in the powder throwing in under the edges, which is the result of taping in that manner. The real problem that I see is that with cast aluminum pieces such as this, intake manifolds, wheels, etc., is that to get the item to turn out with the show finish we all expect they must be shot HOT, when all of the air has been expelled from the pores...which requires a good knowledge of how it all works...as the powder is shot onto the substrate, it is immediately 'kicking off', and the normal tendency is to keep laying it on, as it appears that there is not enough for coverage...wrong! As the last 2 shots show, there is an extreme buildup of powder, as shown where the tape lifted, hard to tape a surface like that, and never run it around the surface, you would tape from top to bottom, using several smaller widths of tape, rather than one solid run...as previously suggested, strip them (aircraft stripper works fine for the complete unit, otherwise MEK, commonly used in testing of coating, or brakeclean), repolish and enjoy them, possibly you could add detail on other pieces in the system...sorry you've had a bad experience with powder coating as it really is a great product, has been used in the industry for more than 60 years...and yes, fuels, brakeclean and similar chemicals will affect the coating, so always be careful.....
I would put those in a dunk tank, I have a mild solution that will strip the pc work in about 3-5 days, then you are back to square one with whatever he left or did for prep before he powdered, then repowder with a reputable company. the time frame alone blows me away...holy ****! I try and maintain a 5-7 day turn time on everything. pc when done properly will look crisp and clean, not fat or heavy....and yes, thats tape he left on, a sharp razor blade will help lift it.
Having looked at the throttle bodies again after I first posted this thread - they are cast not billet, I am tempted just to strip them back to bare metal, repolish and then shoot them myself with the black tinted ceramic clear coat. I have used the clear ceramic with great results and you can spray the tinted version with an HVLP gun. It's just a little wet so caution and spraying thin coats are advisable. Once it sets up this stuff is bulletproof and impervious to automotive chemicals, including brake fluid. I have used it to clear coat polished aluminum and it never needs to be repolished as it does not dull or haze. Thanks guys for all the helpful suggestions and for sharing the knowledge. It may be time for a rethink on this whole deal. I have attached a couple of shots of how it looked in the '40 coupe when all polished and it just seems way too blingy (and non HAMB compliant). Coloring the throttle bodies should help and then I intend to swap out the air horns for a set of boat scoops for a more period oriented aesthetic....
My buddy has a restored fire truck that had powder coating built up in the wheel holes, he though all was well and good-n-tight. When going down the road at 50 mph his rear wheel p***ed him, yikes, he got it slowed and curbed, looked for the loose wheel for hours before finally finding it hundreds of yards into a cornfield. Just so much P.C. in the hole that it didn't snug up tight, no one hurt but very fortunate to not ruin a spectacular machine via this oversight. A live and learn story. The industry has very nice plastic plugs of all sizes to plug into holes to prevent this, a must use deal. Powder coating is a great media when properly applied!! ~sololobo~
Really sorry for your experience as other posters have stated. Yeah there's green high temp tape left all over, probably a tape dot edge in the one shot showing an injector port. Man they piled the powder on that part, completely buried the tape edge and then it peeled back from the substrate where they attempted to pull tape. I would guess the prep was also poor and or the powder is under cured. A lot of thermal setting powders will be brittle like hard candy if under cured, they may appear as if they flowed properly (melted and laid out) but the cure temp/duration wasn't met so the cross linking never occurred. Scratch the coating with the edge of a nickel held like a guitar pick so the edge bites into the paint and the paint flies off in shattered little shards. (undercure) It's shocking how many shade tree powder coaters are out there doing this to ch***is etc. Go through all the prep work, spray the powder, under cure it and the customer wonders why his frame is all flaky and chipped up after a few hundred miles. That's just one of the things that can go wrong with an incompetent powder coater, pre treatment (prep) is huge and many guys just don't bother. Too often it's just blast, solvent wipe and shoot the powder. We're currently switching to a non phosphate zirconium based conversion coating process. We're showing substantial gains in corrosion testing in salt spray tests with it. Without a good conversion coating prep you are just bare naked under the paint. If you convert the surface of the substrate by creating a micro thin layer in one of the many pre treat chemistries such as zinc, chrome, iron phosphate, zirconium etc.. You are creating an inert layer on the steel that will enhance adhesion and act as a micro primer that will keep corrosion from running wild under your paint when small paint chips and scratches occur. Without a conversion coating between your steel and your powder, corrosion and moisture will have a hay day running wild under your paint every place it can gain entry through a little stone chip or small scratch. That's where you get your blistering that runs crazy under the paint. I agree with these guys suggesting a stripper soak to get rid of that coating and start over again. <O
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