Author Topic: wet sanding spray painted enclosure: sanding marks?  (Read 2078 times)

Beedoola

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wet sanding spray painted enclosure: sanding marks?
« on: February 12, 2014, 09:03:21 AM »
I've been using spray paint as my method for painting enclosures. They usually turn out pretty good. Sometimes, however, I get maybe one or two particles on the paint on the final coat.

I wanted to know if I could wet sand to get the imperfections out and whether there will be any visible sanding marks once I shoot the clear coat.

Thanks.

jimijam

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #1 on: February 12, 2014, 09:14:36 AM »
no there won't but you should probably let the paint harden for a while before sanding. I like to let mine sit for a few weeks till the "gummyness" is gone. if when you wet sand you get little nuggets of paint rolling around under your paper if is still too soft for sanding... when i paint I like to lightly wet sand (with a small corian sanding block) the whole enclosure to level the finish before applyng clear.
I store my sanding paper soaking in a tub of water all the time. soaking your paper helps prevent "loading" and it will last a long long time.
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Willybomb

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #2 on: February 12, 2014, 09:21:30 AM »
Use a really high grade of wet/dry, and use a cut/polish compound to finish.  It'll go like glass if done properly.

Gledison

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #3 on: February 12, 2014, 09:38:03 AM »
no there won't but you should probably let the paint harden for a while before sanding. I like to let mine sit for a few weeks till the "gummyness" is gone. if when you wet sand you get little nuggets of paint rolling around under your paper if is still too soft for sanding... when i paint I like to lightly wet sand (with a small corian sanding block) the whole enclosure to level the finish before applyng clear.
I store my sanding paper soaking in a tub of water all the time. soaking your paper helps prevent "loading" and it will last a long long time.
Totally agree!
in addition, im using a toast oven in order to speed up the process. 80 deg C for 30 minutes after every coat. If i see some spots, just sand it off with a 600grit or 1000, clean the surface with isopropanol alchohol, and repeat till i get enough coats (around 20 :(  )
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TNblueshawk

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #4 on: February 12, 2014, 09:53:26 AM »
The micro mesh pads, I used these for sanding down a guitar I nitro'd, might work very well and not show any marks. I've got 2000 grit wet/sand but I'd be inclined to use the even higher grit pads if it was me and I was trying to get a finished look out of it.
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Beedoola

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #5 on: February 12, 2014, 01:25:23 PM »
no there won't but you should probably let the paint harden for a while before sanding. I like to let mine sit for a few weeks till the "gummyness" is gone. if when you wet sand you get little nuggets of paint rolling around under your paper if is still too soft for sanding... when i paint I like to lightly wet sand (with a small corian sanding block) the whole enclosure to level the finish before applyng clear.
I store my sanding paper soaking in a tub of water all the time. soaking your paper helps prevent "loading" and it will last a long long time.
Totally agree!
in addition, im using a toast oven in order to speed up the process. 80 deg C for 30 minutes after every coat. If i see some spots, just sand it off with a 600grit or 1000, clean the surface with isopropanol alchohol, and repeat till i get enough coats (around 20 :(  )
Cheers

Ya I need to get a toaster oven.

I'm using etching primer and I like the look so that's gonna be my finish color.

rullywowr

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #6 on: February 12, 2014, 06:36:11 PM »

no there won't but you should probably let the paint harden for a while before sanding. I like to let mine sit for a few weeks till the "gummyness" is gone. if when you wet sand you get little nuggets of paint rolling around under your paper if is still too soft for sanding... when i paint I like to lightly wet sand (with a small corian sanding block) the whole enclosure to level the finish before applyng clear.
I store my sanding paper soaking in a tub of water all the time. soaking your paper helps prevent "loading" and it will last a long long time.
Totally agree!
in addition, im using a toast oven in order to speed up the process. 80 deg C for 30 minutes after every coat. If i see some spots, just sand it off with a 600grit or 1000, clean the surface with isopropanol alchohol, and repeat till i get enough coats (around 20 :(  )
Cheers

Ya I need to get a toaster oven.

I'm using etching primer and I like the look so that's gonna be my finish color.

Zinc chromate etching primer smells horrible, I think it gives cancer upon exposure immediately...but it does work well!



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Beedoola

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Re: wet sanding spray painted enclosure: sanding marks?
« Reply #7 on: February 15, 2014, 04:31:43 PM »
I didn't get any little balls or niblets forming - that has happened in the past.

I did get some color differentiation on the enclosure and I'm wondering if that will shop upon clear coat, or not. I just did another coat of primer cause a few spots needed more.

Then I'm going to let it sit for a day or two before a final sand and then clear coat.

Hmm, I didn't notice the Etching primer to smell any worse than normal spray paint.