1977 Ventura build

[Jmr1974]

I got to get this problem nipped in the but, I don’t want to practice anymore. The transom is definitely salvageable, I’m going to work fish eye areas and blend the gel, no sense in sanding it all it looks to good. I must’ve sanded a lot of the contamination out because it didn’t show back up in areas it was previously. Problem is you can’t see the contamination with the naked eye until the gel is sprayed. I’ll never get this thing flipped back over at this rate

[LakeFever]

Once your air system is contaminated it’s hard to get it paint capable if not impossible. The compressor produces a lot of condensation as well as some oil fog from the heat during running. An old school trick was to run a second air line in a garbage pail full of ice water before the filter drier to condense the air fully before it gets to the drier making it easier to catch.

There is the possibility that the fisheyes are surface contaminant too. Once you have fisheyes it’s very hard to get rid of them without sanding them fully off. Even if the contaminant is cleaned out if there is any pinhole remaining the paint tends to roll up around it amplifying the crater effect. This is why I was thinking some duratec putty would be helpful to mush it in and flatten the dimple out completely also covering any contaminant. If your out of duratec you could try this trick with a little bit of gel maybe adding some cabosil and see if that will fill reasonably well?

If you didn’t add a filter drier to your spray set up this will probably keep happening. A new air line might also help too. Those little filters can only do so much. Maybe run a test panel until your confident you have the method down?

[Jmr1974]

Once your air system is contaminated it’s hard to get it paint capable if not impossible. The compressor produces a lot of condensation as well as some oil fog from the heat during running. An old school trick was to run a second air line in a garbage pail full of ice water before the filter drier to condense the air fully before it gets to the drier making it easier to catch.

There is the possibility that the fisheyes are surface contaminant too. Once you have fisheyes it’s very hard to get rid of them without sanding them fully off. Even if the contaminant is cleaned out if there is any pinhole remaining the paint tends to roll up around it amplifying the crater effect. This is why I was thinking some duratec putty would be helpful to mush it in and flatten the dimple out completely also covering any contaminant. If your out of duratec you could try this trick with a little bit of gel maybe adding some cabosil and see if that will fill reasonably well?

If you didn’t add a filter drier to your spray set up this will probably keep happening. A new air line might also help too. Those little filters can only do so much. Maybe run a test panel until your confident you have the method down?

. I’m a carpenter and I use run an oiler on this compressor fur nail guns, this dawned on me while laying in bed last knight. Guess what hoses I’m using to spray??? I’m pretty sure the microscopic oil in the lines is coming out every time I blow off the dust when sanding, which I’m constantly doing it because I’m constantly sanding. I would be chasing my tail if it wasn’t for you helping me. Thank you. I’m going to buy all new spraying eguipment hoses, filters etc. just ordered more gel and duratec for next weekend.

[LakeFever]

I’d say you have it cornered now. All good man just passing on the help so many others here have provided to me too. I wouldn’t have a half decent build without the support from S&F

[Jmr1974]

Spent about 5-6hrs this week sanding off the gel coat that fish eyed on me, bought news hoses filters and all that. Just finished re spraying half the boat. Fish eye city again. Glad I only did half the boat. Time to crack a beer and go cut the grass….

[LakeFever]

Probably air temperature related. The compressor heats the air and it condenses as it leave the spray gun sort of like air conditioning it condenses at that time. Plus the hot air will carry very tiny oil Vapor’s with it. Next time stuff the air line in a garbage pail full of ice and put an entire length of air line coiled up in there. Add your water separator after that tank and those small filters you bought the first time round are a single use deal. That should cure it

there’s aslo a product called fish eye remover that you can add to paint. Might be worth trying a small test panel with some of it added. You only put a squirt in or so. Test panels are your best friend so you don’t waste material or time sanding. Work through til you get it sorted then shoot the hull. You’ll get it, don’t give up.

edit. You can also add a tag on air tank if you can find one. Basically anything you can do so the compressor head doesn’t have to run constantly and generate a lot of heat. Hot air is not good for spraying

[Jmr1974]

I’ll give the ice water a try tomorrow. I bought all new air filters to screw into the spray gun ( disposable ones) also added a water separator at the compressor, all this setup before I sprayed today, temp was around 70 degrees. I’ll try the ice bath next. Every time I load the gun I do a test spray on cardboard ( couple passes) it’s just such a small example tho. Should I put water in with the ice or just straight ice?

[LakeFever]

You want water in the bucket to transfer the heat out of the air. To condense it before it gets to your filter drier. Filter driers are not all created equal either some just kind of look the part and don’t do much. There is one other type that works very well it’s known as the toilet roll filter drier but it requires an assembly. It’s basically a disposable desiccant roll in a drum that the air passes through and soaks up the moisture and it gets all of it. I run something different. Part built, and part bought. I have a couple 12’ vertical drops and a condensation capture system on mine before it gets to the devilbiss air drier. A couple ball valve drains at the bottom and I have a solenoid on the bottom of my tank drain that I blow out first. My process is to drain all my bleeders and always charge the tank the day before. Then the next day I walk in the door spraying the floor with water to keep dust down. I spray the floor again between each coat. Then right before I spray I drain the tank before it runs to get all the condensate out. I hit the two drains again on the drops. Then I clean the filter drier. I always use acetone and fully degrease my air line about 20’ worth from the gun. I also degrease the gun very carefully with thinners or acetone. Then I blow off the paint surface and degrease usually at least twice as mentioned with white terry rags in one direction until perfectly white. I use a yellow tack cloth and lightly go over the surface. Then I mix product and start spraying.

it can be a royal pita to get the air cleaned up enough for this. Anyways just work your test panels til you get the recipe down your so close

[Jmr1974]

Here’s what I’m using for the gun and the compressor. None of its industrial (far from it) but I figured it should work for this one project.

[LakeFever]

That water separator is kinda useless. Those things work by vaporizing the air through that filter which ideally is a desiccant but I believe that one looks to be sintered bronze so it will vaporizing but not pull moisture. They are rated at a micron scale and I’m betting that one is letting plenty of hot moist air with hot oil drops right on by. The compressor being small is probably running constantly during spray which builds a lot of heat which amplifies the problem. Know anyone with a 50 gallon unit you can borrow or trade favors for? Also as much as I’m not wanting to spend your money that filter drier is not for paint work it’s basically junk for this. Usually there’s some cheap auto body supplier around who has off brand yet pro grade stuff that won’t break the bank. It could also just be the nature of your compressor it might be a hot oily sucker and that will be hard to clean even with high caliber filtration. Bummer man

Sometimes these little jobbers do great sometimes they fight ya. Anyways I’d seek out better filtration at minimum and try the ice water trick. See how it goes on the test panels I guess

[Jmr1974]

Would this be a better option or should I not wast my money and get something better.

[LakeFever]

It’s a real desiccant so it can’t be that bad. It’s a bead type which only work as long as they can absorb. You can recharge them in an oven or a hot dry sunny day outside. If they get oil contaminated they need a soapy wash first. Can’t argue with the price I think I’d give it a try and see. Also keep in mind the air line you have now has residue in it as well so maybe blow off a minute or two at max pressure with an air blower before spraying in hopes of clearing it out. Fingers crossed for ya

[transomstand]

I'm a little concerned about the final wash as well. Line contamination is an issue, but if it was real bad I would think you'd have more fisheye. Some of this acetone we get now is recycled crap and I question it's purity. Might want to pick up some Prep-sol or another final wash type product to be sure the surface is as clean as possible. Wash before and after you sand it out. Once you get the fisheye, the contaminate gets in everything, the surface, the sandpaper, the dust, etc.

[Jmr1974]

I'm a little concerned about the final wash as well. Line contamination is an issue, but if it was real bad I would think you'd have more fisheye. Some of this acetone we get now is recycled crap and I question it's purity. Might want to pick up some Prep-sol or another final wash type product to be sure the surface is as clean as possible. Wash before and after you sand it out. Once you get the fisheye, the contaminate gets in everything, the surface, the sandpaper, the dust, etc.

The acetone I get is from Menards. I have an auto parts store that sells auto paint, I was thinking of going there and see if they have some sort of cleaner.

[Jmr1974]

It’s a real desiccant so it can’t be that bad. It’s a bead type which only work as long as they can absorb. You can recharge them in an oven or a hot dry sunny day outside. If they get oil contaminated they need a soapy wash first. Can’t argue with the price I think I’d give it a try and see. Also keep in mind the air line you have now has residue in it as well so maybe blow off a minute or two at max pressure with an air blower before spraying in hopes of clearing it out. Fingers crossed for ya

Talked to a buddy last night about a compressor, he has a service truck used for working on heavy equipment that’s set up with a 50 gallon compressor with a air dryer set up, it runs off PTO. He says I can come get it if I want. Like you said my compressor runs way more than it doesn’t when I’m spraying.