Help with Solvent Pop

[thetorch]

Thanks for the thoughtful response. The pops occurred on the first coat, so it wasn't related to second coats or flash time.

I have a desiccant system and an inline water and oil Separator at the gun. Maybe I need to upgrade my drier to a higher quality one.

[Bill Douglas]

Originally Posted by thetorch

Thanks for the thoughtful response. The pops occurred on the first coat, so it wasn't related to second coats or flash time.

I have a desiccant system and an inline water and oil Separator at the gun. Maybe I need to upgrade my drier to a higher quality one.

I'm pleased to help. I thought the pic's looked like the water issue I had, and the desiccant dryer sure fixed it. My desiccant dryer isn't a terribly fancy or expensive one. It sits on the compressor side of things, just after the ordinary water trap type one that came with the compressor.

I do take the beads (crystals) out and dry them with a hot air gun each time I'm going to use the sprayer. Mine go from blue to pink if they have moisture in them. A minute or two of hot air while being swirled around in a stainless steel bowl works for mine.

[962porsche]

Originally Posted by thetorch

Thanks for the thoughtful response. The pops occurred on the first coat, so it wasn't related to second coats or flash time.

I have a desiccant system and an inline water and oil Separator at the gun. Maybe I need to upgrade my drier to a higher quality one.

if you are getting water and you do have a desiccant dryer it could be from a number of reasons.
like Bill stated you can dry most beads a few times before they will still need to be replaced.
if your compressor is on the smaller side and has to work hard to keep up with a high demand of air uses then at times you would need to go with a bigger dryer.
things to do even when your using a dryer is to make sure it's mounted as far away from the air supply as it can be.
make sure its mounted higher than the air compressor so moisture will be able to drain back to the compressor .
still putting a few loops up and down from the floor to celling before the dryer is a good idea like stated before in the posting replies. with bleeders at the bottom of the loops. this will let you drain any moisture from the air supply line.
another help is to crack open the drain valve just to let a very small amount of air and moisture to bleed out before it gets to your dryer.

[thetorch]

Well, I learned a lot on this project. I think the Nason paint was bad, not that there was any water in the lines. I think the gun + the DuPont Nason was a bad combination for some reason.

My previous post had a decent amount of orange peel, and I burned through one edge while polishing it. I had laid the paint just too thin on one area.

So I sanded it down and took another shot at it. Laid down so flat that I didn't need to color sand at all. Just a little blend and polish and done.

Finished product:

[Bill Douglas]

Congratulations. It looks spectacular.

[Monkey Wrench]

any piston compressor will also put oil in the air. the desiccant filter can have some water filter bowls prior to, then they catch a lot first and you can watch them to see if water is collecting. some have a ball that floats and then it opens the bottom pushing some air out with the water until the ball stops floating then it seals. the desiccant will last longer if it has less water to catch.

you can chill the line, or add a second tank. If its a long line you may find even after you filtered it more can come out. a cheap thing you can do is plumb in a foot or two of drop in metal pipe , the water wants to settle in the pipe and you can add a tap on the bottom to open, It acts as a sediment bowl basically but you can just make that from pipe and fittings.

some add oilers to oil their air tools, don't use those air lines for painting, they are contaminated. If you dont have an oiler or want oily air lines, you can put oil in any air tools that require it when you connect it to the line.

drain your compressor often enough , more when it's humid. you can add an autodrain for about 200 bucks, then it blows off the bottom of the tank for 5 seconds or so on a schedule set by it's timer.

if you dig into it there are ISO standards for air, you can consult a pro and they will help you size and choose your filters or dryers etc to meet the standard. different machines, hospitals etc may comply to set standards for oil or water contamination. in some cases the air quality can affect warranty coverage for certain machinery and the user may be responsible to maintain it because the water can cause a lot of damage to pneumatic systems etc. the bowls dryer etc should really be matched for particulate size , water but also be right for the CFM of the application. Shoes that are too big won't help them work better. If shopping you want the CFM , compressor type, length of run, the quality desired etc, from that, any decent company that supplies comressrs will have techs that can help you make good choices.

the filters and the bowls are nto all made the same there is a big range in quality, some are units with 3 or so bowls in one unit they can also be plumbed separately in a daisy chain. If they are a unit then you need to be able to get the filters and parts from the vendor. If you separate them you can have 3 different brands of filter bowls. Id recommend to try to get parts that are common because you can end up needing to replace it if you cant get the filters easily or if they are super expensive. Ingersoll Rand is a good brand, not the cheapest, but there are many others.

I'd keep some spare filters, If you see them get soaked, throw them away and drain your compressor more. some people try to cheap out and dry the filters. false economy if that causes trouble. If you by a filter bowl arrangement try to get a common brand so the filter availability isn't going to stop what you need to do. dryers work by refrigerating the air, some need them , some don't.

I look upon air lines as tanks as well, they act as tanks, they hold air so if you have a lot of hose that's a vessel, it's just a long skinny one. as the air goes through the hose and sees cooling and maybe goes over a rise or a fall then you can find more water coming out from your air along the way, so you can add filters near the compressor but also at the user end.

I dont know as much about pro painting as you guys but the air quality can be made to meet certain standards. Hospital air is one of the higher ratings for example. you cant be feeding people air from a piston compressor as they would then be exposed to the oil , the oil is caused by blow by from the crankcase of the piston compressor past the pistons rings.. some who use lots of air have screw compressors and they work differently. the loud as hell pancake compressors don't have the oil output issue as its a vibrating rubber diaphragm not a piston so the air is separated from the oil for the crank by the diaphragm, and it won't have pistons.


All I can say about the paint work is I just love that brilliant shade of blue !