Looks like sand in finish?

C

curt b

I spoke with Mr. barry and Mr. andy earlier and thought I would post some pics so they would see what I was talking about. thanks for all the help. IMG_6641 (640x427).jpg

IMG_6643 (640x427).jpg

This happens from time to time and its been kickin my but for a while.
 
obviously that's a test panel right? The little speckles showing the the light reflection is what you're concerned about? It looks like solvent pop to me, the solvents are still trapped and trying to work their way out through the surface leaving the defects you're seeing. Most times is caused from rushing, green undercoats, base applied with little flash time, not enough flash time before clear is applied, a reducer that's too fast, high temperatures. You'll have to lay out exactly what you're doing-proceedure with regards to time, application, and products for the people here to figure this out.
 
That's the back side that won't really be seen but I'm gonna do it over. It's over 2 week old epoxy sanded with 400 wiped with waterborne wax grease remover dryed 1 hour blown of with air tacked and sprayed with 1 coat black single stage did that after about 10 min. Painted the other parts before 2 weeks before this only 1 wheel did this a little I did everthing else pretty much same steps but let it dry about 3 hrs or so. I get this every now and again with clear and single stage I've tried waiting over night, spraying light coats, heavy coats, side ways, upside down and every way in between. I think it something to do with high solids and my gun set up, because I didn't have this problem until about 6 yrs ago. I've beat my head on it until i can think straight so i'm getting good at doin stuff over aint nothing like practice. This is wood but i get it on metal too.
 
I have used spi universal clear twice and didn't get this but i get this with Sherwin Williams 930 clear , finish 1 720 clear and most single stage paint. I can paint regular oil base enamel and it doesn't do this. I have thought about maybe spraying too wet and too much solvent but have tried light tack coats let dry hand slick between coats and still get this in end result. Up until about 6yrs ago i never had this in any paint job, i thought maybe they changed something but i know other painters painting with it and they either don't care how it looks or their lying when they say it doesn't do this with them but i haven't seen their work just talked to a couple about it. I even went somewhere else and painted something to eliminate contamination in my shop and still did it so its got to be something i'm doing but it doesn't do it all the time just 2 or 3 out of say 10.
 
30 min for single stage, 10 to 15 for base. 30min to overnight then clear, I have tried about every kind of times.
 
What activator? what temps? Are you using any reducer in the single stage or clear? Any chance there is porosity in the epoxy primer being it is over wood-just wondering if the W&G remover might be getting soaked into the wood through microscopic holes in the epoxy, wood always wants to breathe and definitely can be a challenge to seal up. Oak is always a nightmare for me.
 
This was all spi with slow activator only in the single stage. I've tried about every temp in the clear reducer before. It does it with metal too just not all the time. That's what makes me think it's a combination of gun set up, and the way I am applying it, I've even pondered stupidity. It does seem like the higher grade paint is more forgiving.
 
Have you used this gun with any fish eye addy?
1. AIR contamination. Reason I ALWAYS use a good bulb filter at my gun,fresh one on later stuff as they have a short spray life.The desiccant gun filters are junk.Either use a desiccant "snake" hose filter and replace it as required or the DeVilbiss black bulb gun filters which are the best I've found for the price along with a properly designed PAINT AIR supply system.Such as a quality,"real" air filter system from DeVille or Sata.
2.Good harder. As well as a good paint FILTER/S.
3. MIXING WELL.
4.Last time you COMPLETELY broke your gun down and CLEANED EVERYTHING,This also requires removing the cup,as crap will build between the cup/gun connection as well as any cup/gun filters.Which I only use with clear.
5.The HOSE your using.Yeah ANY hose can be a moisture/crap trap.Even your OWN...
6.The clear your using is junk.
 
Referring to the S&W clear stuff. NEVER had an issue with SPI Uni. I find out ,it "usually" comes back to gun crap or an air problem.
BTW.Being in the HVAC biz.I have 5/8" or 1/2" plumbing copper feeding my paint filter/regulator setup. I use a 5/8" flair filter drier,which we use to clean the Freon in the high side line,To "clean" the air before it goes to my paint gun lines.This drier is an HH style,meaning,it has a charcoal element inside,which doubles the "cleaning" aspect of the air.I could actually run an aux air line for "fresh air" to me if I wanted,however,I choose to rely on my filter mask,as I has good air exchange from my "booth".Also,You might want to rig up an inline tee with a psi gauge to check the ACTUAL air psi going INTO your gun with the trigger pulled,full max.See MY JUNK for an example.
 
Not a high jack... more a chicken and the egg question
Can you make them go away ?
I am experiencing the same thing.
All SPI epoxy/epoxy sealer /SS/SS cut and now cutting SS/, 50/50 SS/CCx2. No Reducer Med activator.
I attribute it to my 1001 possible goofs. This IS my first rodeo.
I remember Barry saying they tend to only form in the top 1/3 of a coat.
What I find is they seem to stand out about the same time I reach the bottom of my peel. ( there's that extra 1/3 rub?)
I worry I won't find the bottom of them...as I try to sneak up on the clear panel I envision with my 400/600 rinse and repeat cycle.
Is this normal? (yeah yeah I know) and if so whats the recommended steps 320/400 till their gone?, or step up to 600 when they're 90 gone...sooner?
 
I have tried it all 4 different guns, new hoses, I have a regulator with moisture separator at the compressor, a toilet paper filter, a self contained air dryer with compressor, a regulator with desacant dryer in booth and a filter on gun, and yes I've tried it with old and new stuff. I have 4 different gauges but I just got a new iwata gauge and i'm going to set up some stuff and try different pressure, spray distance and time between cleaning and what ever else I can think of until I figure out what i'm doing wrong, I've beat this dead horse long enough so its time to find another horse.
 
I get them in the first coat most of the time so I just sand and redo. Sometimes I does it sometimes it don't. I sprayed spi universal twice the same way I spray everthing else and so far I can't make it do it. It might be something to do with temp, humidity, or flying monkeys, I've beat my head against the wall and for some reason i still think i'm just doing something i aint suppose to. Everybodys got a little forest gump in them somewhere but i'm beginning to think mines taking over.
 
I've not sprayed the "new" epoxy as of yet.I always blocked my epoxy,1:1,2 coats,with at least 24 hr dry,first block 150,and then SEEN what I have to deal with.Then did whatever was necessary next,epoxy,2 coats 20% if it was "bad" blocked 180.Rinse & Repeat,320/400.Yes,I've had "issues" with the "old" epoxy giving me "pebbles" in a straight 1:1 or reduced,I blamed it on the 2nd part/activator/HEAT or me,but I ALWAYS sanded it down before a 50/50 sealer coat which was always "perfect" using a 1.4 gun.LPH-400.Then went on with the "standard" SS procedure.Not too sure about your 50/50 SS deal.I always went SS,2 coats1:1,1:1:1:20%,and if I was content,cleared with 2 Uni.or the old MS.Honestly,I've never had to sand Black SS and have sent several "out the door" as shot. Might be time for a "good" gun an a air system. Could be something deeper.Roll it out in the Sun and let it cook a couple days,roll it back in for 24,and resand it wit whatever it takes to get it flat again,clean it,roll it out again,SEE what you have and roll it back in and go from there.Sometimes,It takes T-I-M-E for $hit to cure out.THEN, YOU can deal with it & it won't be a complete lose.
 
I don't see this in the primer only final color. I've got some stuff to spray this week so i'm go try some different things and see.
 
If this is over wood and the only primer being applied is epoxy, I would guess there are plenty of holes in the wood trapping solvent and then pushing out. I would try a primer filler or polyester filler first. While the epoxy makes for a good durable substrate, it won't fill any small holes. Just my guess after doing a bunch of wood chairs and doors.
 
In the past I have tried painting with not using wax a grease remover and still had this problem. Even though I have a air dryer I'm beginning to think I have a moisture or oil problem that's why it show up sometimes and not others like higher humidity or hotter weather. I use to prime with oil base primer on wood and I would think epoxy with a activator would seal way better? That's why I started using it.
 
I think it's solvent related, somehow. Another thing that can cause this is if you have a fairly thick buildup of uncured primer that gets painted over the uncured primer will pull in some solvent then it has to release it later causing the pop marks.
 
I have tried letting the primer dry 1 day, 5 days, 2 weeks and even a month and it don't matter.you can spray it thick, or light. I painted two trucks in December and January with universal clear and it didn't do it as soon it got hot the problem came back.
 
Idea???

Air pressure at the wall should be 125 or more.
Then try 3-5 more lbs at the gun.

You may not be kicking out the flash solvents with too little SCFM and air pressure.
 
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