HVLP Sprayer and Latex - Question about

[Will Patterson]

Hello All


I have done a fair amount of reading about using an HVLPSpray Gun to apply Latex Paint. I know Latex is thick compared to top coats andother finishes. I have seen videos where people are using wiper fluid anddistilled water to thin Latex by about 20% and it would appear that they aregetting good results. My compressor puts out 6.8CFM and 40PSI which is enoughfor the gun that I am planning to purchase. The CFM requirement of the gun is 4.2 to 7.1 CFM. Here is a link to the gun:


https://www.amazon.com/dp/B001NOU92G/?coliid=I368QMCK8GD38G&colid=74OBKZYHBTAZ&psc=0&re f_=lv_ov_lig_dp_it


Based on posts in this forum, it looks like the minimum tipsize should be 2.0. I could also get a gun with a 2.5 Tip. Any thoughts onwhich tip size would be best?


Thanks, Bill

[John TenEyck]

A lot depends upon which paints you plan to spray. If you use something like General Finishes Enduro White Poly, which has a viscosity of around 100 seconds through a #4 Ford cup, then the 2.0 mm N/N set should work fine with only minimal thinning. But if you want to spray something like SW's ProClassic, which has a viscosity of more like 500 seconds, then the 2.5 mm N/N set would be a much better choice. If you buy a gun with a range of N/N sets then you'll have a lot more flexibility. If you want to buy only one, pick the one with the N/N set that best fits the highest viscosity product you want to spray. And buy a Ford #4 viscosity cup to measure and adjust the viscosity of the products you spray.

" ...people are using wiper fluid and distilled water to thin latex …" Really? Never heard of that. I use GF's Extender when I need to thin WB products; a few percent has a dramatic effect.

John

[Tom M King]

I have a cheap gun very similar to that one that I use for spraying epoxy primer. I don't know what you're wanting to spray latex on, but my first choice is an airless sprayer. With that gun in the link, and a 6.8 at 40 compressor, you might be able to spray one cabinet door with it, and then wait for it to pump back up. The trouble with a compressor like that is that it won't provide usable air very well once the pressure in the tank has dropped below what the regulator is set at, and then tries to play catch up while giving you less, and less air to work with.

If you have to thin latex at all to spray it, your chances of doing a top notch job go Way down. Add to that a compressor that is being overworked, and it's no fun.

[Carroll Courtney]

Always wanted to try one of these which comes in several models.And there is a few Youtubes on these.

[John TenEyck]

I have a cheap gun very similar to that one that I use for spraying epoxy primer. I don't know what you're wanting to spray latex on, but my first choice is an airless sprayer. With that gun in the link, and a 6.8 at 40 compressor, you might be able to spray one cabinet door with it, and then wait for it to pump back up. The trouble with a compressor like that is that it won't provide usable air very well once the pressure in the tank has dropped below what the regulator is set at, and then tries to play catch up while giving you less, and less air to work with.

If you have to thin latex at all to spray it, your chances of doing a top notch job go Way down. Add to that a compressor that is being overworked, and it's no fun.

Tom, respectfully, you've got it wrong. If his compressor can output 6.8 cfm at 40 psi it has more than enough capacity to run that gun w/o compromise for as long as he wants to hold the trigger back. The compressor will likely die an earlier death but it will meet the needs of that gun.

John

[Mike Henderson]

I've sprayed latex with an HVLP gun with a 2.0 tip. I thinned the latex a small amount - maybe 5%. It went on great and finished smooth. I was very satisfied with the results. I don't remember the brand of latex but it was probably Dunn Edwards, which is my local paint supplier.

Mike

[Tom M King]

Tom, respectfully, you've got it wrong. If his compressor can output 6.8 cfm at 40 psi it has more than enough capacity to run that gun w/o compromise for as long as he wants to hold the trigger back. The compressor will likely die an earlier death but it will meet the needs of that gun.

John

I know it falls within the stated specs, but I would be surprised. The trouble I've found with those small compressors is that the air flow is just not consistent. I have a couple of them, and also a couple of two-stage compressors, and have never been satisfied trying to finish spray anything with one of the small compressors. I even changed the stock regulator on one of them, and it didn't help much.

I bought a gun that looks very similar to that, to spray some cast aluminum gutter brackets using epoxy primer because I didn't want to run it through one of the good guns. The gun I bought liked a lot of air. I admit to not remembering the specs of the gun though.

edited to add: I went to my purchases list, and the gun I bought is the exact same gun this thread was started about. I would never put that gun in the hands of someone who has read about spraying latex, with a small compressor, and place any kind of bet on getting good results. I've sprayed paint for over 40 years now, and don't think I could.

[Tom M King]

Always wanted to try one of these which comes in several models.And there is a few Youtubes on these.

I have a battery powered version of that gun. It does okay, but is a lot of trouble to clean. You really need a sink with running water, so you can take it all apart. We only use it if it's a small job, like one side of a house door, and don't want to bother with the big airless rig, and then it takes longer to clean the gun than what we use it for. It's not a terrible job, but still a bit aggravating to take several minutes to clean up behind 30 seconds of spraying.

[Wayne Lomman]

I agree with Tom on this. Small compressors are rated on theoretical capacity, not deliverable air. That being said, if you are patient, you aren't on the clock, and the weather is not too hot, the job will get done. I use a 2.0 tip for everything, no exceptions. I find that a 2.5 tip delivers more material but at the cost of finish quality.

In summary, a 2.0 tip will work for a wide range of materials. Read the tech data sheet for the product you buy and thin as required using the recommended solvent. Wiper fluid (whatever that is) and distilled water? Kind of weirdly unnecessary. Cheers

[John TenEyck]

I know it falls within the stated specs, but I would be surprised. The trouble I've found with those small compressors is that the air flow is just not consistent. I have a couple of them, and also a couple of two-stage compressors, and have never been satisfied trying to finish spray anything with one of the small compressors. I even changed the stock regulator on one of them, and it didn't help much.

I bought a gun that looks very similar to that, to spray some cast aluminum gutter brackets using epoxy primer because I didn't want to run it through one of the good guns. The gun I bought liked a lot of air. I admit to not remembering the specs of the gun though.

edited to add: I went to my purchases list, and the gun I bought is the exact same gun this thread was started about. I would never put that gun in the hands of someone who has read about spraying latex, with a small compressor, and place any kind of bet on getting good results. I've sprayed paint for over 40 years now, and don't think I could.

Tom, I will defer to your experience, since you have me by about 30 years as far as spraying goes.

To the OP, if you want color think beyond paint. There are several WB lacquers available, from TC, SW's, Lenmark (BM), etc. that have viscosities below 100 seconds, and they will be easier to spray than most products classified as paint. I've sprayed a couple of gallons of Lenmark's Duralaq, available at BM. It's a clearcoat finish but can be tinted to any of BM's 6000 colors. TC offers the same with their EM-6500 (I think).

John

[Carl Beckett]

I dont have the years of experience with HVLP, but used to paint autobody with traditional spray guns before HVLP was popular. Then for house projects tried thinning and spraying with HPLV (with a decent compressor), tried the small handheld Wagner sprayers, and finally the airless type (both a larger one which i painted my house and shed and treehouse and a couple interior rooms with it, then recently picked up the Graco handheld airless that was shown in the previous post).

I did not have good luck with thinning (it has to be just right. Helps, but still doesnt make it go smoothly)

I felt the Wagner vibrating head type hand held was a complete waste of money, took it to the dump and put it on the swap table give away

I did a couple projects with the HVLP, large compressor, and thinning (I have three.. one primer with a 2.0 tip, a finish gun (1.3 to 1.5 tip) and a small detail gun. Dont forget to accommodate for pressure drops in the air hose. I dont think smaller compressors are going to work very well. This 'worked', but was a pretty big hassle and doesnt cover as well

My best results by far are with the large airless. It works great I have to say. Yes cleanup is a pain, and dont forget to leave something in it besides water else the piston will rust in place.

I havent tried the handheld version. (picked it off CL for a good price so hoping it does ok for smaller projects and is easier than cleanup on the large one) Do not yet know. Am hoping it works well - I MUCH prefer a sprayed finish over a brush or roller, even if cleanup is longer than the spraying, the total job time might be less.

Not an expert/professional painter. But have went down the path you are on and ended up with the airless approach as the only one I will consider in the future when spraying latex. Yep, will just have to suffer through cleanup. (I still spray auto type finishes with the HPLC, including solvent based/thin finishes for woodworking)

[Rob Young]

A lot depends upon which paints you plan to spray. If you use something like General Finishes Enduro White Poly, which has a viscosity of around 100 seconds through a #4 Ford cup, then the 2.0 mm N/N set should work fine with only minimal thinning. But if you want to spray something like SW's ProClassic, which has a viscosity of more like 500 seconds, then the 2.5 mm N/N set would be a much better choice. If you buy a gun with a range of N/N sets then you'll have a lot more flexibility. If you want to buy only one, pick the one with the N/N set that best fits the highest viscosity product you want to spray. And buy a Ford #4 viscosity cup to measure and adjust the viscosity of the products you spray.

" ...people are using wiper fluid and distilled water to thin latex …" Really? Never heard of that. I use GF's Extender when I need to thin WB products; a few percent has a dramatic effect.

John

I think the wiper fluid would work because it (some?) contain stuff like glycol, which one I'm not sure right now. And since it is mostly water anyway... However, who knows what it does to the qualities of paint in the long run.

I've been using water to thin the acrylic latex paints I've sprayed and a dash of Floetrol to help it flow out. Seems to work just fine for me and a few pieces of patio furniture have had full west sun exposure for 1 and 2 years now with no ill effects (maybe a little fading).

Just for the halibut, looked up the MSDS of Floetrol and its two primary ingredients are.... wait for it...

water
2-propenoic acid, butyl ester, polymer with ethenyl acetate which they give the common name "vinyl acrylic latex"

[Carroll Courtney]

Dang,scratch that ideal off my list.But it just looks like its the answer to painting.

I have a battery powered version of that gun. It does okay, but is a lot of trouble to clean. You really need a sink with running water, so you can take it all apart. We only use it if it's a small job, like one side of a house door, and don't want to bother with the big airless rig, and then it takes longer to clean the gun than what we use it for. It's not a terrible job, but still a bit aggravating to take several minutes to clean up behind 30 seconds of spraying.

[Tom M King]

If you always have a sink available, with hot running water, it's not too bad. It's not as easy to do a really good job with as a high end spray rig though, anyway. It's easy to do a factory finish with good equipment, but this doesn't quite fit in that category.

[Curt Harms]

I think the wiper fluid would work because it (some?) contain stuff like glycol, which one I'm not sure right now. And since it is mostly water anyway... However, who knows what it does to the qualities of paint in the long run.

I've been using water to thin the acrylic latex paints I've sprayed and a dash of Floetrol to help it flow out. Seems to work just fine for me and a few pieces of patio furniture have had full west sun exposure for 1 and 2 years now with no ill effects (maybe a little fading).

Just for the halibut, looked up the MSDS of Floetrol and its two primary ingredients are.... wait for it...

water
2-propenoic acid, butyl ester, polymer with ethenyl acetate which they give the common name "vinyl acrylic latex"

I've used the Floetrol/distilled water combo and it worked with old "latex" wall paint. It didn't produce a furniture grade finish but then I didn't expect it to, I just wanted white. If I wanted a furniture grade finish, I'd use furniture grade material, something like John TenEyck mentioned in his post. One thing that did help with the "latex" was to apply a coat of shellac sanding sealer first and sand it, sanding sealer sands pretty easily. Then apply the paint. I guess it has to do with no grain raising but it made for a surprisingly smooth coat considering it was latex wall paint. I also strained the paint after thinning.