Spray Gun Problem.

[CaptFox]

HELP!

I was trying to spray some silver (Poly Spray) today on a Horzontal Stab with a Graco HVLP with the gravity cup. I had no problems with the Poly Brush Spray coats earlier in the week. Today I could not get anything to come out properly. I tried #3 and #5 tips both with similar problems and I either could not get anything to come out of it or it would come out in in a stream or splatter. When I did seem to get the spray pattern and flow set up correctly between the air and fluid settings it would spray one or two passes and then stop. I finally has to give up for the day.

Anybody have any suggestions? I'm assuming this is a operator problem not an equipment one? I did run out of time and light today so I'll have to trouble shoot more next week. Anybody have any similar problems or any setup advise before I tacke this.

Thanks

David.

 

[Lippy]

I’ve got a HVLP gun and it doesn’t work well for fabric work. I was astonished as it is one of the REALLY spendy top of the line guns, but still doesn’t work well. It will do a wicked good automotive quality job but not fabric work. For fabric we use a #7 Binks. So short answer, get a different gun.

Lippy

 

[Bill Rusk]

It almost sounds like something is blocking the jet. Did you filter the paint? Are you sure there are no chunks that are randomly going through the gun, ie works a couple of passes then stops. Dried paint mixed in with the new stuff?
If you can tell what color you painted last then you are not cleaning the gun well enough.
Splattering sounds like a partially blocked gun or paint with something in it that will clog up the feed or needle areas.

Good luck

Bill

 

[Widebody]

Dave,

Check the vent hole on the lid of your gravity cup.
Sounds like it's plugged to me.

Brad

 

[Steve Pierce]

I agree with widebody. I take my gun completely apart after every job and clean it real good with MEK. If stuff won't come off I use paint stripper. Every time I have the problem you describe the vent hole/tube was plugged. My experience is the opposite of Lippy's. All I have ever used is a Graco HVLP for fabric work. I have a standard unit mounted in the wall of my paint booth and a portable pressure pot on wheels. Have had good service out of both.

 

[CaptFox]

Thanks guys,

I was figuring it was going to be a plugged vent or some gunk stuck somewhere inside... I'll take it all apart and try again next week. It was getting late today so I did not mess with it too much to investigate today.

David.

 

[Steve Pierce]

David, every time I am just going to go in and shoot a quick coat I have a problem like yours. Cathy is usually pretty understanding when I come home way late. :lol:

 

[Lippy]

Steve- What model of Graco HVLP do you have? Is it a primer, paint, or dual purpose gun?

Lippy

 

[Steve Pierce]

Not sure the model. Will look tomorrow and see. It is almost 10 years old. I have two different needle/air cap sets. One for primer and dope and one for polyuretane. It is a suction type gun also. Haven't been willing to let go of the cash for a gravity feed.

 

[JP]

On the Graco HVLP cleaning is critical. I use laquer thinner to clean it with very good results. Any residue or foreign matter will raise heck with the gun. Completely disassemble after you shoot any paint and always give it a good cleaning and problems will be kept to a minimum. I've had fabulous results using the gun--not bad for a total amateur.

 

[CaptFox]

I guess I'd better do some housekeeping on the gun and try again. I was sorta thinking that was the likely problem but wanted get some confirmation before I spin my wheels in the wrong direction.

Thanks again guys. I'll let you know what I find...

D.

 

[CaptFox]

You guys were right!!!

Some of my previous polybrush in the gun had worked its way down the vent tube and the little port into the gun had an polybrush air bubble in it blocking all air to the vent hole tube. Hence my problem I think. I'll shoot another coat later in the week and see if I have better luck..


Thanks again.

David.

 

[bob turner]

I have been using a Binks model 37, but was considering the Graco for the next job. I won't spray the exotics - only dope and acrylic enamel without the hardener, and alkyd enamels. I am interested in other comments on HVLP and dope - you may have saved me $1200.

I guess I know every square inch of the Binks - some guy at a spray gun repair shop stripped the threads, so I had to put a brass insert in, then the seal between nozzle and gun was incorrect . . . I guess I love that old beat-up gun.

Maybe I'll buy a wing rotisserie instead.

 

[Steve Pierce]

Lippy, I am using a Croix CX20 and a Graco Series 900. Graco bought out Croix several years ago. CJ Spray is where I get hoses, parts etc. 800-328-4827 ext 1240 Jim Bryntesen knows these things inside and out.

 

[bob turner]

So how do you like it with dope?

 

[Steve Pierce]

It is all I have ever used so I can't compare but I like shooting dope better than anything else and I consistantly use less product than they say I need for a job. I can spray a spot as small as a dime or a swoth that wide. The gun is very controlable and easy to set, use and clean. When I went out on my own in 1997 I had never painted anything but with a spray can. I had great success with the HVLP except on Aerothane. I ate a lot of time and sanded a lot of parts before I would let it go out the door.

I have a friend who has been doing this way longer than me. He uses a Croix one everything and then his old Binks gun on the final coat. He likes the way it atomizes better. I think a lot of the new pressure guns have screwed the atomization up to get compliant with enviromental regs. I would like to find a good old Binks gun for those polyurehane top coats.