Two part polyurethane error

Alex Novo

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Sep 22, 2019
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25
Morning capitans. Fishish spraying the clear coat and this dots appeared. 3 coats, 20 minutes in between. 2:1 mix. Now sanding to recoat and afraid to make same mistake. Any ideas or suggestions. Thanks in advance
 

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Scott Danforth

Grumpy Vintage Moderator still playing with boats
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did you use a drier on the line? looks like moisture from the compressor.

only fix for that and the orange peal is to sand
 

Alex Novo

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Sep 22, 2019
Messages
25
Yes Sr . I did use a cheap water separator and upon finish there was drips of water on the outlet of the separator. We already sanded and keep looking for small blemishes. Quick question. More activator lower dry time or reverse? Thanks
 

gm280

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Jun 26, 2011
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Usually when I am painting anything I really want to look great, the very first think I do is DRAIN THE COMPRESSOR! Even one day's usage will have water in the compressor. And secondly, try to use a good drier at the gun if you can. Water quickly forms when the air temperature changes. So the closer to the spray pattern you can get with a drier, the better the chances are to keep water out. And if you are using a typical disposable air drier at the gun, take it and allow it to warm in the oven for a while to make sure it is dried out inside. It works at a nice warm low setting. JMHO
 

Bondo

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Quick question. More activator lower dry time or reverse?

Ayuh,..... With the 2-pt. urethanes I use, adjustin' the mix, causes major problems,....
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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most cheapy in-line coalescing filters wont cut it. a good in-line desiccant filter like a QC3 will run about $200+ However for painting, a line dryer is really needed.

for my small or non-critical sprays I do like GM280, I drain the compressor prior to the spray. I use an in-line desiccant filter and a filter at the gun. for spraying vehicles, i call my buddy who has a spray booth and pay him beer.

agree with bondo, dont adjust the mix. simply use the appropriate reducer for the temperature you are spraying.
 

Alex Novo

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Sep 22, 2019
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25
10/4 on all advises. Most likely will go for another round before the weekend.Thanks again and will post en job pictures
 
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