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Agualente Plus primer5/4
Sooo. Im using an airless(titan440i) to spray Agualente plus primer and Im getting random cratering that seems to worsen the thicker the coat. All sources of contamination have been ruled out. I am using a 312 tip with fine screens. Could It be the screen/tip size or am just experiencing the same thing that used to happen with the older ml Campbell formulations and its just something that has to be lived with/worked around.
We use a 308 ff tip with ilva wb very thick thin 3% water works well tried our kremlin with 13 tip didn't work well to thick of a coat seams wb like to be sprayed thin .
I use a 308 for my topcoat but I get some drys pray problems with the thicker primer. i only have this problem with the mlc primer. I use GF Enduro poly for my topcoat and it works perfectly. The problem is that you can still see throught to the cratering that happens with the primer coats
tried the 308 today with no improvement. It is a weird one. I cant see at all how it could be contamination. The top coat(GF enduro white poly) is laying out just fine. Im using an electric sander to rule out exhaust from the air sanders, an airless to spray it, so it wouldnt be air spray contamination, and Im using a vacuum cleaner with brush attachment right before I spray. Ive even tried a damp microfiber towel wipe beforehand. all the same result every time. I shoot it on and within 15-30 seconds these craters start to form sporadically all over the surface, and the larger the surface the bigger the problem
If you can't solve the problems with the primer, maybe you should switch to something else. I use BIN pigmented shellac primer under GF's White Poly w/o problem. The BIN goes on uniformly, sands well, and the GF Poly adheres to it well. GF also makes a primer.
Ive used the bin in the past, and per my testing I found the adhesion to be mostly mechanical(relying on a good scratch). The GF primer is excellent except that it is not stain blocking(a big problem on solid paintgrade lumber as well as refinishes). So far of the primers if have used the chemcraft aquaprime performs the best. However it seems to be pretty toxic so I try to stay away from it. The MLC primer seems to lie somewhere in the middle but this cratering issue has me baffled. Im guessing that it is the same problem that mlc has always had with their wb products and its just being swept under the rug.
Bad batch? I've sprayed the Plus tinted topcoats on a few jobs with no problem, but my supplier was still sending me the older version of the primer, so haven't tried it yet. I have not experienced any cratering since MLC switched to Agualente from the old Aquastar/Polystar product line.
Pat what tip size are you using. Airless or hvlp? maybe the agualente just doesnt like my airless? Ive had this happen with the older formulation as well just not this profuse
I spray the primer with a turbine gun, and the topcoats with an AAA with a .09 tip. I doubt your problem is tip-related. Some products are just finicky, but cratering/fisheyes is usually related to some kind of contamination. Can you spray with a different rig to rule out your spray rig?
Yes. I can try using my hvlp pressure pot set up. what needle size do you use. I cant see how it could be contamination when all other brands and products are working just fine
I use a 1.5 or 2mm tip for primer. Going back to the frustrating days of the older MLC products, I could never figure out what was causing the cratering. Humidity? Temp? Stearated sandpaper? Never had it happen with the primer as I recall. I'm hoping it's an isolated thing that you're going through, since Agualente is my main product for pigmented jobs. Try a different can, if possible.
well it seems to be something with the airless. I sprayed it through my gravity gun and got one small crater. I brushed it out at 6 wet mills and no craters. brushed it out after spraying shop air all over the surface from what i would imagine to be my dirtiest line and no craters. tried with the airless and nothin but craters. This is with a new gallon by the way. Could it be the throat seal liquid?
Interesting theory. I don't use the throat seal oil with my pump (CA Technologies AAA) because I remember reading something years ago that if you're spraying waterbased to use water instead. Been doing that for at least 8 years with no problem.
well that may just be it. sounds like im gonna have to break down the pump for a thorough cleaning then switch to using water as the TSL
The cratering sounds like solvent-pop. And, the thicker it is applied, the more the problem will occur. The top layer is skinning over (drying) before the material below.
Try thinning with distilled water. That may help.
By the way, I talked to someone from MLC a few months ago. They told me that the Agualente primers and the Agualente Plus primers were the same. There was no change in the formula. Just a change in the name to match the new topcoat names. There was a change in the topcoat formulas for both clear and pigmented.
The Polystar crater problem is a red herring. The primer never cratered as Pat noted.
I've never experienced cratering with the Aqualente when spraying it with hi transfer gravity guns.
I suspect it might be the airless setup.
So I took apart the airless and cleaned it. everything short of disassembling the upper piston section. cleaned everything in alcohol then soapy water. Cleaned out the throat seal section and replaced the TSL with water. Ran alcohol then soapy water through the pump, and after all that it is still doing the same thing. Yes it has something to do with the airless but I dont think it is contamination. Could too fine of screens and/or the wrong tip be doing this? The only thing I can think of is that the velocity of the material is too high causing some errant particles to hit the surface too hard causing a crater like effect? If I move to a larger tip I could slow the material down. Maybe this would help? I called ML Campbell and they would not offer any recommendations. All they said is that there are too many types of spray systems out there for them to be able to give me any help and that I would just have to experiment with it.
Do the craters start out as bubbles? Or does the finish lay out and the craters slowly form? Classic fisheyes have a distinct appearance and tend to be around 1/8 -1/4" diameter.
If there's bubbling occurring, it could be due to something called "shearing", which is unique to spraying WB finishes with a pump. Search the forums and knowledge base for "microbubbles" and "shearing" to read up.
Attach a pic if you can.
No its not bubbling at all. The craters start to form immediately as it is laying out. So i dont think its pump shear.
Maybe my pump needs a rebuild idk? but General finishes, Target coatings, Chemcraft and Valspar Zenith all spray just fine out of the pump. This is only happening with the MLC primer. And im wanting to use this primer because other than this cratering problem it has all of the attributes that I need in a primer.
I also have this issue spraying with a gravity gun/pressure pot. I can find no pattern, it's very frustrating.
I just sprayed a couple of gallons of this and was very impressed with the product. Can you please explain what you mean by "pretty toxic"? I am wondering if I missed something and need to take additional precautions in the future. Although, I generally spray solvent based CV products, so my safety protocol was still followed...
Mark V, If you are used to spraying CV then its probably childs play. My potocol is closer to handling latex paint. I do have good ventilation and I do use a mask, but thats about it. I clean up with soapy water and occasionally alcohol. I noticed that it had a lingering odor that made me feel nauseated so I switched back to the MLC.
To everyone else who contributed and may be wondering, IT was the tip size. A 1.2 orifice or less was messing it up. I got a 314 titan fine finish tip today and the results were a 95% improvement. On a base cabinet end panel I only got one crater and I was able to spray back over it and wash it in. I was able to drop the gun pressure and slow the material down by quite a bit which i think is what helped.
From what I read on Chemcraft website that waterborne primer can be top coated with clear solvent base cv.
I was told by my rep that you could topcoat it with anything.
By slow down I mean the velocity of the spray. The chemcraft can be coated with anything. According to chemcraft it must be topcoated within 8 hours of being sanded.