100 mesh gun filter clogging in airless paint sprayer

[Viz]

I've been using a Campbell Hausfeld AL231010LE airless sprayer for years, and most of the time it works perfectly. The latex primer just used on the exterior of the house went on fine. The paint however, Sherwin Williams Super, is clogging the 100 mesh gun filter so frequently I can't paint for more than 5 minutes before cleaning it. Several filters (all new), have even collapsed, indicating the pressure has been too high or/plus the flow is too restricted.

I've used Floetrol, about 1 qt per gallon. I've strained with 5 gallon cloth filters, and nothing has helped. There is a screen filter on the end of the pickup tube that sits in the paint bucket, but nothing is clogging that. And yes, I've thoroughly mixed it with a 5 gallon mixer on a drill, after the store did their thing on their machine too.

This must be a high solids paint, but I think the 100 mesh filter might be too restrictive. 60 mesh seems to be the recommended size for latex, but, there are none made in that size for this gun. 100 mesh is it.

So, turning to wiser minds on the forum, a couple of questions, and any other suggestions you might have to make this work.

1) How prudent would it be to just take out the mesh filter and paint without it? I know it will probably wear the tip out faster, but I can't get the house painted at this rate.

2) For future use, has anyone rigged up some kind of fine filter, external to the spray gun and pump, but in line to the gun ? Newer units, like Grayco, have larger filters and seem to be in line also. I'm not ready to give up on this unit, but I would like to get this filtration issue solved.

3) Will pantyhose/stockings filter any better than the 5 gallon cloth mesh filters?

Thanks,
Viz

 

[beamrider]

What exactly are you using, Super flat/satin/gloss/etc. I just shot out a house in Super satin, and had no problems. Used a 415 tip IIRC, at about 2200psi. And the only time I don't use a 100 mesh filter in the gun, is when I'm shooting Loxon.

Not familiar with the model sprayer you're using. Does it have another filter somewhere, besides the rock catcher on the ****? Is it possible you have an obstruction in the hose somewhere? Have you tried a new seat/seal in the tip guard?

Also, did you do a complete clean on the unit after shooting the primer? I tried going from primer to regular paint once, and only once, without a full clean. Took me about 5 minutes to ruin a gun filter, was fine afterI broke it down and cleaned it.

 

[Viz]

Thanks Beamrider. I'm using Super Satin. The sprayer is pretty old actually, about 1995 or so. The only filter is the gun filter, I double checked that, and the hose flows with no problems there. The tip guard is new (with the seat/seal).

I completely cleaned the unit after priming too, yes. I clean it after every session (I don't switch from primer to paint in the same day. Homeowner, not professional).

When I primed and painted the other 3 sides of the house, I did have a few issues when painting, but nothing like it is on this last side. Oh, and the tip is a 515. Not sure about the psi as there's no gauge on the unit.

Since my first post, I did find there are in fact 50 mesh filters available, but they'll take days to get here. I'm getting them anyway, to have for whatever, but in the meantime, I've got to get this last coat on while the weather cooperates.

Viz

 

[beamrider]

you might try stepping up to a 517, or even a 519. Or 417/419, if you can find them. In this case, orifice size might be more critical than fan width.

You can also try keeping the unit pressurized with Pump Armor for a while, it lubes everything and will keep tint particles from sticking to things.

Also, what I do when I'm finished cleaning the pump, is run water thru, and then pressurize the system to max. Turn the pump off, and then snap open the prime valve. Sends a shock wave thru the system, and helps dislodge any remaining crud.