HVLP Spraying - Gravity vs. Siphon vs. Pressure Pot

[dtbingle]

Looking to pick up a paint sprayer to tackle spraying latex paint on two doors in the basement. Maybe an smaller shed in the upcoming future (10x10'ish) and kitchen cabinets (all likely latex paint). I already have a 5hp 60 gal compressor so air is fine. I don't want to buy an airless. Painting time is not a concern and if the project is large enough (exterior paint job), I would rent an airless.

Whats are pros and cons of each type of hvlp sprayer - gravity fed, attached bottle siphon fed, detached pressure pot?

As of right now I'm leaning towards the HF #93312 spray gun kit. Reviews say it sprays latex paints well with a bit of thinning. 1.8mm tip, separate bottle means less weight at spraying hand, larger 64 oz bottle means less time spent refilling. Anyone use this kit?

 

[Cope]

Hoses to clean and a pot to drag behind me. No thanks. I'd look at either a gravity feed set or cup set. eBay has a decent set up that I bought several years ago to paint some fencing. The same seller has individual components.
http://www.ebay.com/itm/190814266493?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[shoot summ]

I have a Fuji HVLP system with a gravity gun. My only complaint is the size of the cup/reservoir. There are other gun/cup variations available I think, I would but one with a larger cup next time.

 

[dtbingle]

Hoses to clean and a pot to drag behind me. No thanks. I'd look at either a gravity feed set or cup set. eBay has a decent set up that I bought several years ago to paint some fencing. The same seller has individual components.
http://www.ebay.com/itm/190814266493?_trksid=p2060353.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Hadn't really thought too much about this part of the gun use. Think you convinced me to go with a 'gun-on-bottle' setup. TCP seems to have a decent selection - especially $40-50 range of guns with 1.8-2.0 tips that should work with latex fairly well.

I have a Fuji HVLP system with a gravity gun. My only complaint is the size of the cup/reservoir. There are other gun/cup variations available I think, I would but one with a larger cup next time.

Is this one of the 20oz'ish bottles?

 

[VoodooCLD]

I have the harbor freight pressure pot gun that i bought for doing exactly what you are talking about. Mine is the older non HVLP version which comes with a larger tip. It was the best $40 i ever spent. You need to add an extra diaphragm style in line pressure regulator (no cheater valves) right at the gun so you can get the proper pressure at the gun without triggering the over pressure valve on the pressure pot.

Get an air regulator like this.

http://www.northerntool.com/shop/to...AmaZuv_OVbsVndXrGZpy8vwhSgY7FYSVFIaAs_g8P8HAQ

I sprayed my kitchen cabinets, an 8x12 shed, 2 closets and some trim with it.

Edit: Just looked at your link. That looks to be the exact same unit i have. Buy it!

 

[Todd.Brock]

The pressure pot isn't a bad idea for a larger projects. I use the purple $10 HF gu to spray woodwork, doors, etc. I use a 1qt mixing cup from HD. Fill with paint to 12 oz. mark, add 2oz of water. That gives you an 6 to 1 ratio which is perfect for shooting latex trim paint, and it's the perfect amount for the 20 oz cup. Works great. Practice with water in the gun on the driveway to get the pattern.

 

[Homebody]

A 12 dollar Harbor Freight purple gun is all you need for those projects. Don't look at anything but an HVLP.

 

[VoodooCLD]

A 12 dollar Harbor Freight purple gun is all you need for those projects. Don't look at anything but an HVLP.

I disagree with this statement for latex. If you go non-hvlp and pressure pot you can spray the latex straight from the can, no thinning required. I also did it with a 2 hp 10 gallon compressor.

 

[dtbingle]

I disagree with this statement for latex. If you go non-hvlp and pressure pot you can spray the latex straight from the can, no thinning required. I also did it with a 2 hp 10 gallon compressor.

Question - so what determines a sprayer's ability to shoot latex? I would've thought it's mostly tip size and pressure. I guess in other words, how would running the same tip size and pressure in a pressure pot be able to shoot latex straight out of a can vs. a gravity fed hvlp sprayer?

EDIT: Did some googling and it makes sense now. Pressure pot gives more control of fluid being able to pressurize the pot and what goes to the gun, whereas flow on others are mainly based on the tip size.

 

[Stooge]

Hadn't really thought too much about this part of the gun use. Think you convinced me to go with a 'gun-on-bottle' setup. TCP seems to have a decent selection - especially $40-50 range of guns with 1.8-2.0 tips that should work with latex fairly well.

I have one of those TCP global guns with the 2.5mm tip that I bought for thick stuff and metal flake, works well enough for the price and should be able to handle latex paint. I don't know if I would want to go smaller than a 2.0 tip for latex, and im pretty i would have clogging issues with the 1.8 sharpe gun i have, but it looks like some of the reviews for this one, (the 2.5 one I have) people are spraying latex with it and seem to be happy with the results. tcp says the cup is a liter so almost half of that harbor freight syphon one, but refilling a cup seems like less work than cleaning out the hoses

https://www.amazon.com/gp/product/B001NOU92G/?tag=atomicindus08-20

 

[VoodooCLD]

Question - so what determines a sprayer's ability to shoot latex? I would've thought it's mostly tip size and pressure. I guess in other words, how would running the same tip size and pressure in a pressure pot be able to shoot latex straight out of a can vs. a gravity fed hvlp sprayer?

EDIT: Did some googling and it makes sense now. Pressure pot gives more control of fluid being able to pressurize the pot and what goes to the gun, whereas flow on others are mainly based on the tip size.

Yep. With a pressure pot the latex is forced under pressure up to the tip, then you use a separate regulator to control the air for good atomization. With a gravity feed the thick latex wont gravity feed to the tip fast enough and you'll have intermittent spraying which will mess up your smooth finish. A band aid is to thin the paint so it will flow to the tip better, but this just makes the paint more transparent which won't cover as well, as well as potentially screw up the self leveling/ sag resisting features of the paint.

I find spraying the paint without any modifying is best.

Also, HVLP guns are meant to run very low pressures. This is fine to atomize very thin solvent based auto paints, but its very difficult to atomize thick latex with low pressure. The conventional spray guns will run at like 40-50 psi and break up the latex great. You do get more overspray, but when latex is $35 a gallon vs $150 a quart of automotive paint, it's less important.

 

[RV8guy]

Most of my painting is all done with a pressure pot. Pretty much any time I'm spraying more than 1 quart at a time. It's faster and you can spray in any position. It is a bigger investment in equipment though. For just a couple of jobs I would go with a gravity gun. If you can, get a spray gun that can get an adapter for 3M PPS cups. Best thing since sliced bread. They make clean up a breeze.

 

[jubilee]

I spray latex with pressure pot. Thin 20-30%. 60-65lbs

 

[CobraRed]

Yep. With a pressure pot the latex is forced under pressure up to the tip, then you use a separate regulator to control the air for good atomization. With a gravity feed the thick latex wont gravity feed to the tip fast enough and you'll have intermittent spraying which will mess up your smooth finish. A band aid is to thin the paint so it will flow to the tip better, but this just makes the paint more transparent which won't cover as well, as well as potentially screw up the self leveling/ sag resisting features of the paint.

I find spraying the paint without any modifying is best.

Also, HVLP guns are meant to run very low pressures. This is fine to atomize very thin solvent based auto paints, but its very difficult to atomize thick latex with low pressure. The conventional spray guns will run at like 40-50 psi and break up the latex great. You do get more overspray, but when latex is $35 a gallon vs $150 a quart of automotive paint, it's less important.

What tip size do you use with a pressure pot gun and latex?

 

[Todd.Brock]

Sherwin williams pro- classic has guidelines for thinning with water. I think it shoots just dandy. I start with a good primer, like Glidden Gripper paint, also thinned same amount. And then a quick knock down with a sanding sponge, wipe down and then blow off with air gun and then back to spraying. The finish is so smooth. No orange peel, no runs, etc. it's a hell of a paint applicator for 10 bucks. I found it as a last resort b/c airless and HVLP systems put out too much material for doors and trim. Here is my wainscoting project that was sprayed with HF. I am a belieber....

 

[VoodooCLD]

What tip size do you use with a pressure pot gun and latex?

I use this exact kit from harbor freight with an additional regulator as mentioned above.

https://www.harborfreight.com/professional-spray-gun-kit-93312.html

I believe it comes with a 1.8mm tip

 

[Jazz1]

The pressure pot isn't a bad idea for a larger projects. I use the purple $10 HF gu to spray woodwork, doors, etc. I use a 1qt mixing cup from HD. Fill with paint to 12 oz. mark, add 2oz of water. That gives you an 6 to 1 ratio which is perfect for shooting latex trim paint, and it's the perfect amount for the 20 oz cup. Works great. Practice with water in the gun on the driveway to get the pattern.

Thats good advice to practice to check pattern. I just bought the purple HF gun. First thing I ever bought at HF. What I don't like is HF will not allow us to order online from Canada. We have to order over the telephone. On a positive note HF phone sales folks speak the Kings English clearly

I'll be shooting single stage on my truck as soon, or maybe later. I have the paint