WHAT DID I DO WRONG/HOW DID I MESS UP?

[Guest]

THIS IS A TOPIC WHERE YOU CAN POST PICTURES OF PROJECTS YOU MESSED UP. YOU CAN ALSO USE THIS TOPIC TO ASK FOR ADVICE AND TO GET INFORMATION SO YOU DON'T MAKE THE SAME MISTAKE TWICE. * PLEASE BE SURE TO GIVE ALL INFORMATION AS TO WHAT GUN YOU WERE USING, WHAT TYPE OF POWDER, ETC...

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Looks like no-one is messing up-Kool

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Looks like no-one is messing up-Kool

Haha... give it time, they will come... I know I will be posting here often LOL.

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Juan]

Looks like no-one is messing up-Kool

Haha... give it time, they will come... I know I will be posting here often LOL.

same here!

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Lol what good timing for this thread...... outgassing at its finest....just pulled this from the oven, PBTP Diamond Clear Acrylic over brand new raw aluminum tripower air cleaner top. Sorta figured this might happen so I just did one of the set with no out gassing to see if it would. Stripping as we speak and next round with outgassing first.

Shot with a GEMA Optiflex-C
settings were
50% powder output 4.5 Nm3/h total air output
10uA 100 kV

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Cool a thread I can call my own. You know I will use the sh...I mean heck out of it.

Harley

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Took long enough to get it on board after I ask about doing one here in September. I guess PBTP gets credit for my idea?

But glad its here. It might help a lot with problems in one location I hope and that's why I suggested it.

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Well here we go... got my first issue for this thread!

This time it has to do with wrinkle black. I did a valve cover a few days ago with and it turned out great, it's for my own car and it hasn't been installed yet although it has been through a bunch of hands and bouncing around the house and car without any problems.

Tonight I decided to coat my intake with the same wrinkle black. It's a 3" aluminum pipe. So I did the usual, stripped it down to bare metal with Aircraft Stripper, washed it down, blasted it, washed it with denatured alcohol, and off gassed it at 450 for 45 minutes.

Coat it, throw it in the oven, cure it for about 30 minutes (took just over 15 minutes to get to 400, then cured it for around 10 minutes and let it sit in the oven for an additional 5 with the elements off). Let it sit around for a little over an hour while it cools off and as soon as I touch it I see a small imperfection on one of the small brackets attached to the pipe, I figured no biggie, it's just a tiny out of pace wrinkle but I still run my nail over it... it flakes off very easily. Weird, so I run my nail through another small area and the powder just comes off in tiny flakes.

The best way to describe it is like wiping the sugar off a churro I guess. If I use a razor blade then it comes off very easily.

I think I coated the same amount as I did on the valve cover, the finish looks identical on the intake and valve cover which I think is a good sign that I coated them the same way.

I have only changed ONE thing in the entire process, my blasting media. I gave aluminum oxide 70 grit a shot since it's all the local store had in stock (I always use glass beads 80 grit). I don't like the way this media works. It makes the surface dull and feels rough. It doesn't give it the polished look that glass beads can do. It seems like no matter how much I was the part afterwards it just doesn't feel or look clean, like it's dusty.

Is there something special I have to do with aluminum oxide or should I just avoid it? Can this actually be my problem? Maybe I cured it too long? I thought Wrinkle Black (S&S) was pretty overbake stable, and so far it seems like it. What do you guys think?

[wiseguyz]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

I'm pretty sure it's not your media, Juan. That's all I ever use. I agree that AO leaves a much coarser feeling finish, but that's what you want for maximum powder adhesion. If you're talking about a thin metal intake pipe, it's quite possibly an overcure issue. Unless I'm doing a heavy cast piece, a wheel or something similar, it's rare that I need to leave anything in the oven more than 30 minutes total. Maybe someone else who has had a similar issue will chime in. I've never had a flaking issue with the wrinkles.

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Lol what good timing for this thread...... outgassing at its finest....just pulled this from the oven, PBTP Diamond Clear Acrylic over brand new raw aluminum tripower air cleaner top. Sorta figured this might happen so I just did one of the set with no out gassing to see if it would. Stripping as we speak and next round with outgassing first.

You are very wise to minimize your exposure by doing just one....

Shot with a GEMA Optiflex-C
settings were
50% powder output 4.5 Nm3/h total air output
10uA 100 kV

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

I'm pretty sure it's not your media, Juan. That's all I ever use. I agree that AO leaves a much coarser feeling finish, but that's what you want for maximum powder adhesion. If you're talking about a thin metal intake pipe, it's quite possibly an overcure issue. Unless I'm doing a heavy cast piece, a wheel or something similar, it's rare that I need to leave anything in the oven more than 30 minutes total. Maybe someone else who has had a similar issue will chime in. I've never had a flaking issue with the wrinkles.

This is my second guess... Remember last week when I was asking the difference in time to heat up a part during off-gassing and after it's coated. Well the part took around 20 minutes to reach 400, although it held 350 for a long time before making the jump to 400. Coated it and stuck it back int he oven, took about 5 minutes to reach 400, but I went with the previous 15 to 20 + 10 cure. The part was in there for a good 35-40 minutes total.

It's also a 2 piece intake, so when I saw the problem on this pipe and I immediately shot the oven off with the other part that had been baking for 20 minutes. I tested the second pipe this morning and it doesn't show any signs of flaking or peeling... I guess I'll strip that first pipe and try again curing it for only 15-20 minutes.

Anyone else know or think that wrinkles and overbaking for 10-15 minutes would be an issue? Keep in mind this was a thin layer also, I didn't do a very heavy coat, just enough to cover the part.

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Alright I'm stripping the part again and will shoot it shortly. Any tips? How thick of a coat am I looking for in S&S Wrinkle Black?

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Juan]Alright I'm stripping the part again and will shoot it shortly. Any tips? How thick of a coat am I looking for in S&S Wrinkle Black?

I'd shoot for about 3 - 3.5 mils. By the way, after I read your posts again, you most likely overcured the S&S wrinkle cures at 375 (pmt) for 15 minutes.

It was definitely an overbake issue. I kind of hot-flocked the part this time around (110-120) then stuck it in the pre-heated oven at 425. Within 5 minutes the IR gun read 380-390 on the part. I lowered the oven temp to 400 and cured for an additional 13 minutes and let it sit in the oven after it was off for about 2 minutes. Pulled it out and cooled off for about an hour, much better this time around... it no longer flakes off with my stubby finger nails

It was just weird before, like the powder had cured but in two different layers. A base layer of 0.00001 mil (super light coat) that actually stuck to the part, and the top coat that would just chip off. I'm guessing the overbaking is what caused the "two coats" to separate.

Lesson learned and once again I'm glad it was on one of my own parts... I still love this powder and just placed an order 15 minutes ago for a few more pounds, so pictures of my engine bay will follow shortly!

Thanks again everyone!

[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

I had gas tank from a 77 Gold Wing the guy wanted done in black and he wanted it coated on the inside. So, I took to a friend of mine that runs the Gas Tank Renu and had him do the inside only. No blasting outside. I got it back and blasted it on the outside and coated it. What you see in the first pic is actually the second time around.

The first time was as bad, and when I run it through the oven, it smoked worse then anything I've ever had in there. Really filled the shop.

I blew it off after blasting, sprayed with a metal prep (cleaner, degreaser) and alcohol, propane torch and cooked. Basically the same thing the second time, only I stair stepped the oven temp. Still smoked pretty good. Came out like the 1st pic.

The 3rd time around, after it was blasted again, I cleaned it with the Purple cleaner and then I steam cleaned it. Run it in the oven bare and after it cooled I coated it again and cured. Came out really good. (see 2nd pic).

But the coating, after three times in the oven, was flaking off on the inside. So I had them blast the inside only and had them to only coat the inside and I took it back and run it through the oven. No harm to the powder.

My thoughts on what I think caused the problems is the smoke from the coating and when I blasted it, it didn't get rid of it, just drove it in and when I heated it (cure cycle) it released it from the metal.

So I figure the next time, I will coat it first and then have the inside coated, as they only run the cure for the inside coating at 350 deg. Just need to make sure they understand how to handle it and not scratch it.
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[Guest]

Re: WHAT DID I DO WRONG/HOW DID I MESS UP?

Good Jobba