spotty second coat

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sawdust1
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spotty second coat

Post by sawdust1 » Wed Nov 06, 2019 5:25 pm

I have a question about putting on a second layer.
I sandblasted aluminum, epoxy first layer, flowed it out. Second layer is polyester clear matt for UV protection. When I applied the second layer I kept getting thin spots like I was looking at a dalmation dog.
Any thoughts?
Not obvious after cooking.

David

weldguy
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Re: spotty second coat

Post by weldguy » Thu Nov 07, 2019 10:21 am

Not sure what would cause that but at least it flowed out and looked good in the end. If you find out let me know because I have had similar issues.

conradestrada
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Re: spotty second coat

Post by conradestrada » Wed Dec 30, 2020 1:03 pm

That is caused by a poor ground

ccoatings
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Re: spotty second coat

Post by ccoatings » Wed Feb 03, 2021 9:49 pm

Sounds like back ionization, I second the post about poor ground. How close is your ground rod?

sawdust1
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Re: spotty second coat

Post by sawdust1 » Thu Feb 04, 2021 12:02 am

No idea actually!

jessienc
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Re: spotty second coat

Post by jessienc » Thu Jun 03, 2021 12:32 am

back ionization from spraying with the gun to close, its charges little spots in the metal. i started holding the gun farther away and haven't had any issues since

weldguy
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Re: spotty second coat

Post by weldguy » Thu Jun 03, 2021 11:19 am

jessienc wrote:
Thu Jun 03, 2021 12:32 am
back ionization from spraying with the gun to close, its charges little spots in the metal. i started holding the gun farther away and haven't had any issues since
Thanks for the tip, I will give that a try :Like :Like

adbuch
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Re: spotty second coat

Post by adbuch » Sun Jul 04, 2021 12:46 am

jessienc wrote:
Thu Jun 03, 2021 12:32 am
back ionization from spraying with the gun to close, its charges little spots in the metal. i started holding the gun farther away and haven't had any issues since
:Like :Like :Like :Like :Like

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