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Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Fri Jun 18, 2021 9:28 pm
by morrisey0
I am planning to dive into PC'ing a 10T tub tomorrow, and am trying to get everything in order. Since this is a brand new technique to me, I just wanted to see if anyone had any experience they wanted to throw my way.

Soaked the tub in Greased Lightening for a couple of days, rotating and replacing medium as needed, and got 90% of the anodization off. There are loads of scratches, sketchy / rough aluminum on the bottom, and places I had to hammer to straighten out this POS tub that make it a great candidate for a first PC attempt. If I somehow destroy this one, the actual pan is warming up on deck. Beyond anodization removal, all I have done is scuff the whole thing with scotch-brite. This is all the prep I am planning for the aluminum. The scratches are character. :) Again, I try to build runners, not pretty things.

For coating, I am planning on masking the needed countersunk holes with screws while coating the bottom, then remove all that to coat the top.

The baking process will hopefully involve suspending the tub above the baking sheet via all thread and brakeline, but that just exists in my head right now, and will work that out tomorrow.

Please give me any tips you have!!

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sat Jun 19, 2021 8:06 pm
by mikea96
You don't need screws in those holes they will still fit fine once powder coated and if not just hit the holes with a countersink plus once you powder coat over them and bake the coating you won't get them out unless you were going to remove prior to baking. But I think if you don't coat the holes the screws might sit funky.

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sat Jun 19, 2021 8:27 pm
by morrisey0
Yea, the plan is to coat the bottom with the screws in, and then let them fall out, and then coat the other side. Again, just a theory plan and no clue if that will work.

Didn't get anything done on it as planned today. I ended up working out a deal on a RC10T2 about an hour away from me, so made that trip in the morning. Then hit every flea market on the way home, which took more time. And then since it is nice outside, I am supposed to "go outside" and "do activities." Such a bummer! :wink: Tomorrow will be boat day, so unless some maritime failure happens quickly, there will be no hobby time tomorrow. Work load is looking light for Monday though, so maybe at least some test coats happen that afternoon.

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sat Jun 19, 2021 9:17 pm
by TRX-1-3
morrisey0 wrote: Sat Jun 19, 2021 8:27 pm And then since it is nice outside, I am supposed to "go outside" and "do activities."...
:lol:

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sun Jun 20, 2021 4:04 pm
by morrisey0
Choppy as heck on the river today, so only a half day boating. So, got a little hobby time.
mikea96 wrote: Sat Jun 19, 2021 8:06 pm You don't need screws in those holes they will still fit fine once powder coated and if not just hit the holes with a countersink plus once you powder coat over them and bake the coating you won't get them out unless you were going to remove prior to baking. But I think if you don't coat the holes the screws might sit funky.
I asked for advice, and I was nicely given some, and I did what? Ignored it! :roll: Mike, I apologize; and you are right! Dealing with the screws to mask the countersinks was so much more trouble than it was worth! I will not be doing that again.

I thought today was a relative success, until, you know, I looked at the baked part for the first time! Not a complete failure, but pretty close. This is what is apparently called outgassing. There are a few possible reasons for it, but I am hoping it is simply my lack of properly cleaning the part prior to coating, or applying too much coating at once. I doubt it is an issue with the aluminum, or the original anodizing process; I am pretty sure it is all bad technique.

attempt 1 outgassing 1.jpg
attempt 1 outgassing 2.jpg
The bottom came out about 80% on the positive side. A smudge I didn't see (this side would have been down during my final coating) and a few pinholes (again, outgassing), but nothing difficult to fix.
attempt 1 bottom done.jpg
Here are a couple of pics of how my, now known to be terrible, process went:
attempt 1 jig.jpg
attempt 1 bottom coated.jpg
attempt 1 tub ready.jpg
attempt 1 baking.jpg

Here are my lessons learned for the afternoon:

1) already knew this, but it is confirmed, this process is messy! This is definitely a workshop or garage project, and not a spare bedroom / hobby room project. Give yourself at least a solid 6' x 6' area to work. Disposable 9 x 12 plastic sheeting drop clothes are my recommendation. Make your mess, then wrap it up and toss it.

2) this process is SO delicate! Yes, the process uses electric charge to attract the coating to the metal, but once there, it isn't holding on all that well. Draft of air, quick touch, sneeze, look at it wrong ...... and it is coming off! This is why adding steps like using screws as masks and coating a tub in two separate phases with a manual flip in between them doesn't work! Is is a simple, delicate process, and if you overcomplicate it, you will screw it up. This is why pros hang a piece and coat it from all directions at once, and then put the hanging piece directly in an oven. Simple.

3) this HFT powder coating system works as well as all HFT pneumatic tools ....... pretty poorly. Its only real problem is that it randomly just coughs up a big poof of powder. Doesn't provide a nice constant flow.

Next steps:

Sand away the bad areas and feather it out well or just remove most of what is there.

Properly clean all exposed areas.

Coat and bake hanging. I got to thinking and realized that my toaster oven doesn't know its relative position in this world, so why not use it vertically? It has a few vents on the side, but set it on one of its own racks, and insulate that from my workbench with some firebrick, and we should be good to go.
oven vert.jpg

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sun Jun 20, 2021 5:51 pm
by jwscab
Always do a preheat on the part for a bit of time and then let it cool and apply the powder. That will prevent outgassing from contaminants.

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Sun Jun 20, 2021 5:55 pm
by morrisey0
jwscab wrote: Sun Jun 20, 2021 5:51 pm Always do a preheat on the part for a bit of time and then let it cool and apply the powder. That will prevent outgassing from contaminants.
I have read that before, and will certainly do it next time. Thanks!

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Mon Jun 21, 2021 9:18 pm
by morrisey0
I am going to rate today's powder coating activities a solid "good enough for gov't work!" :D

Don't love the results, but proud of them as a first attempt project. This chassis will be fine for the rig it will built around, and if I decide I should have done better, I can work on the second one. But, simple fact is that this chassis looks 1000 time better than the old one, and it has a solid PC coating that should provide plenty of protection.

Proper cleaning, pre-baking to release any contaminant off-gassing, and hanging the chassis vertically all helped to create a great result. The only bad part of the final product is that I did not take all of the problem surfaces (from the first attempt) down to bare metal, and I only feathered them thinking it would all settle out. It really didn't and I should have taken each bad surface down to bare metal, or maybe another coat or two of paint would even it out. The worst parts are in the tub, and most of that is going to get covered up, so I will sleep well at night.

attempt 2 baking.jpg
attempt 2 bottom done.jpg
attempt 2 tub done.jpg

My biggest problem now is that I have been so concerned about the chassis that I haven't done anything to prep the rest of the parts of the rig. Time to get to work on them!

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Mon Jun 21, 2021 11:33 pm
by mikea96
That looks much better!

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Tue Jun 22, 2021 8:32 am
by TRX-1-3
Looks great. All those little imperfections will not stand out when all the other parts are in place. I was thinking "suspend the chassis somehow" rather than supporting it in the oven. Then you turned the oven on its side. Well played!!

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Tue Jun 22, 2021 12:11 pm
by jwscab
That's a nice job much better. It looks like you have a nice thickness on there. Some applications are so thick you have to trim the countersunk holes and fitment is an issue. One reason I don't like powder coating but I like that.

Re: Any Last Minute Advice For DIY AE Tub Powdercoating?

Posted: Thu Jun 24, 2021 9:30 pm
by morrisey0
I didn't want to start a new thread, but does anyone have a maker / color that is very close to AE gold pan color? I understand that AE gold pan color comes in about eight different varieties, but any leads would help. I can't find any local places that sell actual PC paint, so it isn't like walking into Lowes or HD with a piece and matching it up to samples. So far, I have to go by internet colors, or order $2-3 samples of everything that may be close. :(

Attached is a pic of a B1 on FB right now, and at first I really liked the PC "gold" of the pan, but when compared to the shocks, it is night and day. Gold pan gold is very orange!
rc10 gp fb pc.jpg