SPI matte black mixed 4-1 is laying down grainy.

Osh

New Member
And by grainy, it looks like sand in the finish. Filtered twice, once with paper filter and then with 3M liner and lid. Activator looks good and clear not yellowed out like some old activators. Is the 4-1 the culprit? NO water in the line. Not fish eyes, been around long enough to know what they look like.
 
@Barry might need to help with this one. I've never had any issues with that product. More info like purchase date and date that the activator was opened might be helpful. Maybe even a photo.
 
I've had this problem with matte clear. Spraying at low temperature was the problem I think. Something like 65 or lower. I had to heat up the clear to get is to spray and look right.
 
The actual date on the product is 3/25/19 probably purchased it somewhere around late '19. Was at least 70 degrees out when sprayed. For the life of me I can't figure out why the 3M lid strainer would effect it.
 
i have never had that problem with the spi matte black ss but i have had it with the gloss black. the matte black i keep here usually sits around a long time too. takes me a couple years to get through a gal. for the gloss blk, the pigment clumps together if it sits for a couple months. this was a couple years back. barry replaced it with a gal that was supposed to be fixed but that one was exaclty the same. hate to say it but i just ended up switching to utech for my ss. white and other colors were no problem. not sure if that is what is going on in your situation but thats what it sounds like. very fine grit in the finish.
 
I switched to 125 micron strainers for everything but metallic a long time ago, maybe that's why I don't see these problems. If the material has been exposed to freezing temps, that could cause some pigment to not disperse back into the mix. Also if the activator was opened in 2019, it could easily have gone bad. I can't speak for @Barry but I'm sure he and SPI would want to be helpful. I think the matte black is an excellent product so it's a new one on me for anyone to be having problems with it.
 
Old urethane activator will go "seedy" and you can't tell it till you spray. Everything will look fine until you spray it.
I may be wrong but I don't ever recall urethane activators changing color or getting yellowed. Epoxy activator darkens but urethanes are clear and stay that way. . If anything urethane may get cloudy when old but not yellow.
How old was the activator? When did you first open it? Has the product ever been exposed to freezing temps? (like in an unheated garage) My first instinct would be that this is an activator issue. Second would be it was exposed to sub 35 degree temps at some point. Those would be the most common with old/bad activator being the most likely.
 
Could it be that your air dessicant is breaking down (attrition) and causing this? I just went through this on my homemade drying column when some dessicant carried over, got trapped in the filter can and rattled around as it slowly broke up and landed in my epoxy. I cleaned everything up and sprayed base today without issue.
 
Looks like I have a few more things to think about. Garage never gets below 55, I recently changed out the dessicant in a new muslin bag then the toilet paper filter and then for more insurance I use the orange ball gun filter.
 
If it was stored at the 55 temps, then inside the can is 50 at best.
It won't spray so warm can up.
 
If it was stored at the 55 temps, then inside the can is 50 at best.
It won't spray so warm can up.
That's the coldest it's ever been over night. The overhead furnace blow's on the cabinet where it's stored. In the colder months the garage is warmed up to the mid seventies long before I shoot anything. I've been doing this a while so I'm not blowing cold paint onto cold metal. It's been 0 degrees outside and I'm working in a t-shirt inside.
 
The actual date on the product is 3/25/19 probably purchased it somewhere around late '19. Was at least 70 degrees out when sprayed. For the life of me I can't figure out why the 3M lid strainer would effect it.

Matts dont like strainers, period.
And they cannot be made to work.

Solves the problem with every call I get like this and it's the first question I ask.
I just now had time to read and see this.
 
Matts dont like strainers, period.
And they cannot be made to work.

Solves the problem with every call I get like this and it's the first question I ask.
I just now had time to read and see this.
[/

I just blasted and e-coated a few small parts, I'll try it without straining when I get a chance.
 
Back
Top