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nsjuice
09-29-2006, 11:13 AM
I did a Fender last night, based fine.

Then I layed the first coat of clear on and it fisheyed.. not the big ones.. Small little ones that look like Pinholes.

They're only in certain areas but numerous.

How do I tackle this??

Redo? or Scuff with 800 (wet or dry?) and clean, then reshoot?

or what is the best way to go at this.

Frustrated. Easy job taking too long.

Thanks.

Phil V
09-29-2006, 03:49 PM
What brand and number of clear did you use ? (wasn't Kirker was it ?) also which number hardener did you use ?

nsjuice
09-29-2006, 07:45 PM
Not kirker..

U-Pol.. dont have the numbers at hand.

well, i sanded the coat and it was impossible so i just reprimed and so on.

i just finished the new coat.. and..

i see specks.. looking like either air bubbles or bad air line..

not too much but noticable on top of black.

Is there such a thing as not shaking the Clearcoat Bottle???

sorry.. newbie here. :\

Thanks.

Serge
09-29-2006, 09:10 PM
It should be stirred slowly not to introduce air in it...and only if it looks like there is something that needs stirring back in from the bottom of the can...

If it based fine and the resulting clear has fine pin holes I would suspect either air entrapment or a solvant reaction/trapping of some sort...It can be caused by a few things like poor atomization or laying the clear on too thick or too many coats or not enough time between coats.

You should let the basecoat dry for at least 30 min before clear coat, I actually take a beer and do something else for 60 minutes before I go in with clear...Then, each coat of clear should go on wet, not so wet that it would run and then you should wait for the clear to be sticky to the touch, not stringy. If you touch the clear and it forms small filaments between the surface and your finger as you pull it away, it's not ready to recoat. The ideal recoat window for clear is when the clear is sticky. In this case, more dry is not better, some clear coats are finiky this way as if you let them become hand slick (not sticky) they might not adhere...so monitor this closely between coats.

As for repairing air or solvant entrapment well, it depends how deep it is but it usually involves sanding it off and re-doing...

Hope this helps,

Serge

Len
09-29-2006, 11:43 PM
Serge
Are you saying that you can spray bubbles out of the gun that can then be part of the finish?????

Phil V
09-30-2006, 08:43 AM
I was trying to figure that one out myself.

Serge
09-30-2006, 05:47 PM
Any one put a quart of clear on the shaker? It form a foam on and in the clear coat and some micro bubles. In theory, if your droplets of atomozed material are bigger than the micro bubles they could make their way to the surface...well that's the explanation...does it happen...with a good gun...???

Micro bubles would then be trapped as they would not have time to migrate to the surface...

Maybe you guys got me there...Hmmm...Never questionned this one...

1 1/2 cent worth...

Serge

Iceman
10-01-2006, 08:18 PM
I've seen it occur spraying clear on furniture. Even the some of the clear poly's for furniture state stir do not shake. Just my 2 cents...:)

Len
10-01-2006, 10:03 PM
Well... I don't understand why anyone would even stir clear since it doesn't have anything that will settle out. But if you DO shake it you will still need to pour it into a container for mixing with hardener and reducer. When you pour it the bubbles should float to the top AND you could mix improperly because the bubbles could make the level different than if it had no bubbles. Since a spray gun uses the paint from the bottom of the cup AND the clear is usually quite thin, I would think that the bubbles would float to the top quite quickly and become a non-factor. Also we should realize that when a gun sputters it's because air bubbles are being injected into the paint stream from a leak somewhere in the gun and they don't cause bubbles in the finish.... at least none that I've ever seen.

Serge
10-02-2006, 08:12 AM
I guess that the colision clear coats that move alot don't have time to settle much as the stock turns quite fast. Some House of Kolor clear coats will sometimes live on a shelf for a year before you use them and they do have a slightly noticeable deposit in the bottom, probably one of the additives that settles there. If you mix it in, it will not settle back for a long time...I have also seen that in other clears, when I open a new can I shine some light into it and if I see any cloudy deposit in it I stir it up...

There are a large number of papers on micro bubbles in urethane caused by pumps, shakers and stirring, but like you Len I have not seen any bubbles in my finishes that can be traced to that, but then again, I never shake my clear coats...

Maybe I should mix a little batch and put it in the shaker to froth...Maybe a late cofee machine could induce some nice frothy foamy micro bubbles in there...

Down to 1 cent worth...

Serge

dave_demented
10-02-2006, 09:16 PM
id be very curious as to how that'd turn out serge

Jon E
10-04-2006, 10:02 PM
In theory, if your droplets of atomozed material are bigger than the micro bubles they could make their way to the surface...well that's the explanation...does it happen...with a good gun...???

I have accidentally sprayed too heavily in an area and seen hundreds of tiny bubbles instantly appear in the clear that look like solvent pop, but they always float up to the surface and disappear within in a minuet or two before the clear sets up.