Author Topic: Clearcoating advice  (Read 2604 times)

Bret608

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Clearcoating advice
« on: August 15, 2013, 08:49:04 AM »
I know people have touched on this in lots of other threads, but I thought it might be good to start a specific thread in this area for folks who are noobs to this particular part of the enclosure finishing process.

I clearcoated a translucent gold enclosure from PPP this weekend. It didn't need it on its own; I just did so because I used a waterslide decal.

So, here's my question: the top came out looking really good. The sides are still shiny, but when I touch them they feel just slightly "matte" or something. I happen to have some 1200-grit sandpaper from Small Bear. Would this be appropriate for wet-sanding those sides a little smoother?

Not sure why the sides came out like that. It was a touch humid, and my Rustoleum clear was running a bit low.

gtr2

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Re: Clearcoating advice
« Reply #1 on: August 15, 2013, 08:52:20 AM »
For me, that happens when the coat was to light.  It usually happens on the sides when you are spraying the enclosure top up, because we don't want runners.  I don't worry much about it, but you could buff it provided you have enough coats.

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Bret608

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Re: Clearcoating advice
« Reply #2 on: August 15, 2013, 09:53:45 AM »
Thanks Josh! I just may have enough coats--I actually went on pretty heavy when I saw I wasn't getting runs. Like I said, the can was starting to run out though.

So would that sandpaper be okay for buffing it, or should I use some less harsh method?

I agree, I'm not too worried over it since it didn't dull the shine or anything.

wgc

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Re: Clearcoating advice
« Reply #3 on: August 15, 2013, 08:42:21 PM »
Spray the sides first, then the top.  The overspray from the sides on the top will melt into the top when you spray it, at least with lacquer.

Your existing problem is either a too thin coat like already mentioned, or overspray from the top, or you are too far away.

It takes a little practice but you're looking for that happy middle ground where the spray droplets are wet enough that they flow together and smooth out as they dry but not too much so that they continue to run and sag or drip.  The other side of things is being too dry and too thin that the spray droplets can't flow together.

That said, better to be too thin since you can respray and get enough build to be able to wet sand and rub and polish.  If your sides are too thin it will probably show a witness line between the clear and base coat when you sand.

Sorry if any of this is obvious, but sometimes it's the littlest things that trip us up the most.
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Gledison

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Re: Clearcoating advice
« Reply #4 on: August 16, 2013, 01:11:02 AM »
Im forwarding to you an idea ive got here in the forum.
Use a little piece of paper with toothpaste for buffing!
Its a very mild abrasive and i have done on my Credible hulk swirling coat and looked crystal like glass!
Ahh, and will smell fresh!!
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Bret608

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Re: Clearcoating advice
« Reply #5 on: August 16, 2013, 07:27:46 AM »
Toothpaste, eh? That may be the way to go! I do like minty fresh pedals.

Willybomb

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Re: Clearcoating advice
« Reply #6 on: September 18, 2013, 11:32:14 PM »
I use wet and dry folded into a small square.  Keep it wet, and drag it down the enclosure - I don't bother with circular motions in this case as I usually don't want to take much off - just straight lines.  Then I polish with a cut/polish compound, brings it up nice.

I'm going to ry the toothpaste thing though.  Baking soda based ones might work best...

gordo

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Re: Clearcoating advice
« Reply #7 on: September 19, 2013, 07:59:45 PM »
Damn Gledison, you beat me to it.  When plastic car modelling was still a big deal (at least when I was a kid) it was the method of choice for a glass finish.  Plain old Crest (if they still make such a thing) or similar is preferable or anything that advertises "whitening".  Last time I bought toothpaste there were about 400 different kinds.  {puts away old-man rant soapbox}
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gordo

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Re: Clearcoating advice
« Reply #8 on: September 19, 2013, 08:02:09 PM »
Also the foam polishing pads for an electric drill from Stewart-MacDonald do a great job.  If you get creative you can build a stand for the drill and bring the box to the pad rather than the other way around.  And can still use toothpaste...
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Gledison

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Re: Clearcoating advice
« Reply #9 on: September 24, 2013, 01:28:05 PM »
Damn Gledison, you beat me to it.  When plastic car modelling was still a big deal (at least when I was a kid) it was the method of choice for a glass finish.  Plain old Crest (if they still make such a thing) or similar is preferable or anything that advertises "whitening".  Last time I bought toothpaste there were about 400 different kinds.  {puts away old-man rant soapbox}
hehehe, well, it worked for me like a charm.... and yeah, the toothpaste im using is the colgate whitening..eheheh( I should get some endorsement...:P)
If i fart a lot,  it means that i'm a Gas expert ?