# More hvlp gun problems



## fromthenorthwest (May 2, 2012)

Seems like there's problems every time I try to use an HVLP gun. They will work great for a second then they will either stop spraying all together or spray a tiny amount of paint. The funny thing is if I'm holding the trigger down and back way off on the air pressure to the point where it just sort of spills out of the gun or comes out in texture-like patterns, material will come out just fine. It's only if I have the pressure at a higher level where it needs to be for atomization that it wont shoot. I can also get material to come out if I turn the tip diagonal and use the pencil pattern , but either full fan pattern is clogged. Anyone have an idea what the deal might be? If there is a clog I don't understand why it would still come out when I turn the pressure down or to the pencil pattern. I have three guns are all Titan, one is elite and one is a 2, and I'm not sure about the third.


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## irishjim21 (Feb 2, 2017)

fromthenorthwest said:


> Seems like there's problems every time I try to use an HVLP gun. They will work great for a second then they will either stop spraying all together or spray a tiny amount of paint. The funny thing is if I'm holding the trigger down and back way off on the air pressure to the point where it just sort of spills out of the gun or comes out in texture-like patterns, material will come out just fine. It's only if I have the pressure at a higher level where it needs to be for atomization that it wont shoot. I can also get material to come out if I turn the tip diagonal and use the pencil pattern , but either full fan pattern is clogged. Anyone have an idea what the deal might be? If there is a clog I don't understand why it would still come out when I turn the pressure down or to the pencil pattern. I have three guns are all Titan, one is elite and one is a 2, and I'm not sure about the third.


Are you using a gravity cup gun? Sounds like your blockage is up top. You need air relief from the top of the cup. There should be some sort of cap. To confirm this try spraying with the lid off


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## fromthenorthwest (May 2, 2012)

irishjim21 said:


> Are you using a gravity cup gun? Sounds like your blockage is up top. You need air relief from the top of the cup. There should be some sort of cap. To confirm this try spraying with the lid off


Its actually a siphon style, I've cleared out the check valve and also the uptake.


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## cocomonkeynuts (Apr 14, 2017)

I was running into this problem with my apollo with siphon fed cup. In my case I kept finding material on the inside of the spray cap and what I found was that I would occasionally tip my gun upside down and material would make its way past the one way valve. When running siphon cup I'm more careful not to do this otherwise I will switch to 3M pps cups or a pressure pot and fully eliminate the issue.

Was spraying some shelving with command. 1.5mm and B-HS cap with a siphon cup. thinned to about 1sec between drops on a paint stick. I've recycled the material a few times now so I'm not sure where the thinning ratio is as I don't usually measure anyway

FYI running gravity fed is much easier to push paint grade materials than siphon.

An easy way to check what's going on with the gun is to pressurize the cup, disconnect air to the gun. then squeeze trigger. Cup should still be pressurized and you should see material flow from the tip. Today when I did this I found my cup was not pressurized at all. I disconnected air hose from the cup and turned on air. The check valve was partially blocked and the line going to cup was completely blocked. Replaced them and sprayed first coat 12 shelves using <1 quart thinned material.


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## fromthenorthwest (May 2, 2012)

cocomonkeynuts said:


> I was running into this problem with my apollo with siphon fed cup. In my case I kept finding material on the inside of the spray cap and what I found was that I would occasionally tip my gun upside down and material would make its way past the one way valve. When running siphon cup I'm more careful not to do this otherwise I will switch to 3M pps cups or a pressure pot and fully eliminate the issue.
> 
> Was spraying some shelving with command. 1.5mm and B-HS cap with a siphon cup. thinned to about 1sec between drops on a paint stick. I've recycled the material a few times now so I'm not sure where the thinning ratio is as I don't usually measure anyway
> 
> ...





cocomonkeynuts said:


> I was running into this problem with my apollo with siphon fed cup. In my case I kept finding material on the inside of the spray cap and what I found was that I would occasionally tip my gun upside down and material would make its way past the one way valve. When running siphon cup I'm more careful not to do this otherwise I will switch to 3M pps cups or a pressure pot and fully eliminate the issue.
> 
> Was spraying some shelving with command. 1.5mm and B-HS cap with a siphon cup. thinned to about 1sec between drops on a paint stick. I've recycled the material a few times now so I'm not sure where the thinning ratio is as I don't usually measure anyway
> 
> ...


Thanks Coco. Think it's time to look into the gravity fed. Im usually running airless with the fflp tips but am trying to up my finishes as ive had this 115 practically fall in my lap...just cant get the darn thing to work the way i know it can!


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## finishesbykevyn (Apr 14, 2010)

fromthenorthwest said:


> Seems like there's problems every time I try to use an HVLP gun. They will work great for a second then they will either stop spraying all together or spray a tiny amount of paint. The funny thing is if I'm holding the trigger down and back way off on the air pressure to the point where it just sort of spills out of the gun or comes out in texture-like patterns, material will come out just fine. It's only if I have the pressure at a higher level where it needs to be for atomization that it wont shoot. I can also get material to come out if I turn the tip diagonal and use the pencil pattern , but either full fan pattern is clogged. Anyone have an idea what the deal might be? If there is a clog I don't understand why it would still come out when I turn the pressure down or to the pencil pattern. I have three guns are all Titan, one is elite and one is a 2, and I'm not sure about the third.


 I find when shooting latex, it helps to thin your product. Also Strain your paint. This is most important as there are no filters in the hvlp guns and can clog super easy. I too use a gravity fed style cup with a 1.4 tip. All the same I still prefer an airless for top coats on cabinets. Way faster and more mil thickness.


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## Holland (Feb 18, 2011)

I sometimes have trouble with latex and HVLP for fine finish work. The hot air causes the paint to dry too fast, and does funny things to the finish.


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## cocomonkeynuts (Apr 14, 2017)

Holland said:


> I sometimes have trouble with latex and HVLP for fine finish work. The hot air causes the paint to dry too fast, and does funny things to the finish.


Air shouldn't be too hot if it is your probably running wrong tip size or under powered turbine


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## CApainter (Jun 29, 2007)

One of the things I learned about spraying conventionally, was to adjust the fluid needle all the way open when determining fluid pressure from the pot (without air flow). Once I was dialed in with the fluid pressure I would introduce air with the cheater valve and adjust the fan accordingly. I rarely adjusted the fluid needle.

Cup guns were always a hassle for me. I prefer gravity fed any day of the week, although you can't beat a pressure pot for industrial applications.


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## cocomonkeynuts (Apr 14, 2017)

CApainter said:


> One of the things I learned about spraying conventionally, was to adjust the fluid needle all the way open when determining fluid pressure from the pot (without air flow). Once I was dialed in with the fluid pressure I would introduce air with the cheater valve and adjust the fan accordingly. I rarely adjusted the fluid needle.
> 
> Cup guns were always a hassle for me. I prefer gravity fed any day of the week, although you can't beat a pressure pot for industrial applications.


Opposite for me, I start with air wide open and fluid closed.
I'm constantly changing my fluid volume as I switch from round to fan to round but fogging etc. I hardly touch my air once set


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## CApainter (Jun 29, 2007)

cocomonkeynuts said:


> Opposite for me, I start with air wide open and fluid closed.
> I'm constantly changing my fluid volume as I switch from round to fan to round but fogging etc. I hardly touch my air once set


I got accustomed to determining fluid pressure first because the viscosity of industrial coatings can vary dramatically. I needed to be able to adjust the pot pressure first in order to make sure I had adequate fluid volume at the nozzle. Especially with lengthy lines that are elevated. The arch of fluid coming out of the gun could range from two inches to two feet depending on what I was spraying. With the fluid needle opened, I could control the amount of material needed at any instant with the trigger rather than adjusting the needle. Needless to say, the more fluid the more air pressure is required.

I use the same practice with gravity fed, but instead of determining fluid flow by pneumatic pressure, I let gravity determine the flow. With that said, many low viscosity materials can benefit with a fixed needle adjustment.


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## cocomonkeynuts (Apr 14, 2017)

CApainter said:


> I got accustomed to determining fluid pressure first because the viscosity of industrial coatings can vary dramatically. I needed to be able to adjust the pot pressure first in order to make sure I had adequate fluid volume at the nozzle. Especially with lengthy lines that are elevated. The arch of fluid coming out of the gun could range from two inches to two feet depending on what I was spraying. With the fluid needle opened, I could control the amount of material needed at any instant with the trigger rather than adjusting the needle. Needless to say, the more fluid the more air pressure is required.
> 
> I use the same practice with gravity fed, but instead of determining fluid flow by pneumatic pressure, I let gravity determine the flow. With that said, many low viscosity materials can benefit with a fixed needle adjustment.


Ah yes. I pretty much always have the same viscosity whether its latex or oil as I thin quite a bit and spray almost always with 1.5


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## fromthenorthwest (May 2, 2012)

finishesbykevyn said:


> I find when shooting latex, it helps to thin your product. Also Strain your paint. This is most important as there are no filters in the hvlp guns and can clog super easy. I too use a gravity fed style cup with a 1.4 tip. All the same I still prefer an airless for top coats on cabinets. Way faster and more mil thickness.


Thanks Kevyn, and 10-4 on the thinning and straining...still having the problems with siphon feed. Are you shooting cabinets flat rather than hanging them? I believe you use Advanced quite a bit right? That stuff level out pretty nice? I've only sprayed it vertical (a few trim packs and man doors), had problems with it running but it does lay down very nice.


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## fromthenorthwest (May 2, 2012)

Holland said:


> I sometimes have trouble with latex and HVLP for fine finish work. The hot air causes the paint to dry too fast, and does funny things to the finish.


Yeah that's the other problem I get with it, a bit of dry spray in there like a fine grit sandpaper.


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## fromthenorthwest (May 2, 2012)

CApainter said:


> One of the things I learned about spraying conventionally, was to adjust the fluid needle all the way open when determining fluid pressure from the pot (without air flow). Once I was dialed in with the fluid pressure I would introduce air with the cheater valve and adjust the fan accordingly. I rarely adjusted the fluid needle.
> 
> Cup guns were always a hassle for me. I prefer gravity fed any day of the week, although you can't beat a pressure pot for industrial applications.


Thanks for the pointers with adjustments, I'll try starting with the fluid full open next time I fire it up.


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## fromthenorthwest (May 2, 2012)

cocomonkeynuts said:


> Opposite for me, I start with air wide open and fluid closed.
> I'm constantly changing my fluid volume as I switch from round to fan to round but fogging etc. I hardly touch my air once set


I think that's about how I do it now, clock the arrow on 12 then ease in the fluid until it I get a good amount.


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## cocomonkeynuts (Apr 14, 2017)

fromthenorthwest said:


> Yeah that's the other problem I get with it, a bit of dry spray in there like a fine grit sandpaper.


Sand paper is often a thing I experienced starting, then the guy I work for would yell at me to thin the material more.


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## RH (Sep 7, 2010)

I pretty much gave up shooting latex in mine due to so many inconsistencies. Stains and well thinned oils seem to be good choices in an HVLP. But, as others have already said, thinning, straining, and the right tip/pressure…


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## finishesbykevyn (Apr 14, 2010)

fromthenorthwest said:


> Thanks Kevyn, and 10-4 on the thinning and straining...still having the problems with siphon feed. Are you shooting cabinets flat rather than hanging them? I believe you use Advanced quite a bit right? That stuff level out pretty nice? I've only sprayed it vertical (a few trim packs and man doors), had problems with it running but it does lay down very nice.


Yes I'm still using Advance for cabinets mostly .I shoot my doors flat. It flows out like a sheet of glass. If I spray my boxes, I use a 208 and try not to lay on too thick. Although most times we just brush and roll the boxes. I've done a few fireplaces with Scuffx and it also sprays out very nicely. Which product are you using?


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## Holland (Feb 18, 2011)

cocomonkeynuts said:


> Sand paper is often a thing I experienced starting, then the guy I work for would yell at me to thin the material more.


do you thin most products more than 15%?


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## cocomonkeynuts (Apr 14, 2017)

Holland said:


> do you thin most products more than 15%?


Yes I would say most latex closer to 30% with a 1.5 but I don't really measure. I would like to experiment with other sizes but The way I've been doing it works fine


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## fromthenorthwest (May 2, 2012)

cocomonkeynuts said:


> Sand paper is often a thing I experienced starting, then the guy I work for would yell at me to thin the material more.


Good to know.. amazing how many more variables there are to dial in then with an airless.


finishesbykevyn said:


> Yes I'm still using Advance for cabinets mostly .I shoot my doors flat. It flows out like a sheet of glass. If I spray my boxes, I use a 208 and try not to lay on too thick. Although most times we just brush and roll the boxes. I've done a few fireplaces with Scuffx and it also sprays out very nicely. Which product are you using?


Im using scuff x for the most part. Drop 8 to 10 oz of extender in a gallon and spray vertical with a 3 or 410. Lighter colors come out pretty nice but dark colors seem to show a little bit more orange peel. I've been thinking about switching to spraying flat and adding more extender or switching products to get a little nicer finish with the airless. I sprayed some Emerald trim urethane flat and the doors came out almost like glass, can't quite get that with the scuff x unless potentially addding more extender.


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