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Jacob Atwell
04-13-2019, 7:34 AM
I have a 26 gallon kobalt compressor that is rated at 45 scfm @ 90 psi, and I am wondering if I could use it to do some light spraying. Painting is my least favorite thing when it comes to projects, and that may be just because I’m so terrible at it. Due to my complete lack of skills I thought I might give hvlp a try. So what do you guys/gals think? Can my compressor handle it? If it can, can you all recommend a gun that won’t break the bank that I could experiment with? Thanks for the help.

Greg Parrish
04-13-2019, 8:08 AM
For a 4.5 scfm flow rate it may be too low but if you want a cheap way to try it go buy one of the harbor freight guns. Google them and you’ll see lots of folks like them and they are only like $10 with a coupon. Would be a cheap way to try it out before buying a nicer sprayer.

Jacob Atwell
04-13-2019, 9:08 AM
Correct me if I’m wrong, but I was assuming the hvlp guns use something substantially lower than 90 psi. If that’s the case, my compressor should have a higher flow rate at the lower pressure. I just don’t know how much more.

Robert Engel
04-13-2019, 9:22 AM
I think HVLP guns run anywhere from 20-50 PSI & CFM's can range from 5-10. That info is easily checked.

I agree with what Greg said. I've used the HF guns and was quite amazed at how well they sprayed.

Another option to consider is a turbine type sprayer. There are entry level sprayers worth looking at.
Advantages include no worries about air quality, you keep your old compressor. I've found it useful to have a dedicated unit I can move to another location.

Greg Parrish
04-13-2019, 10:05 AM
I have a small Quincy horizontal 20 gal compressor that is rated for 7.1 scfm at 100psi. It theoretically produces high enough flow for spraying but the tank volume means the pump runs non stop. Doable for short stints but for lots of spraying it gets super hot and just cooks. I used it last weekend to clean out the air filter for my Oneida dust collector and I thought I had killed it since it was so hot. LOL

long story short, you should get higher scfm at lower psi but at 26 gals that will be your next obstacle for any amount of continuous spraying or air flow. I still say try the purple sprayer at harbor freight and see how it does. They are almost so cheap if you forget to clean it you can just toss and get a new one.

John TenEyck
04-13-2019, 11:15 AM
What finishes do you want to spray? That's really the place to start.

The HF purple gun has a 1.4 mm N/N on it. It sprays shellac, dyes, and some topcoats really well, but you can't spray paint with it w/o serious thinning. Your compressor is not something you would want to use for continuous spraying, but may be OK for small projects paired with a LVLP gun, which the HF gun is not. 4.5 cfm at 90 psi might give you 6 at 40 psi, and you need about that much to run most LVLP guns you would choose for woodworking projects.

But I do agree with the others. The HF gun sprays low viscosity products very well and even your current compressor will drive it for a few seconds so it's worth giving it a try if that will fit your needs or at least give you enough feedback to decide if spraying is something you want to pursue.

Jim Becker
04-13-2019, 11:19 AM
Greg is correct about the downside to a smaller unit...it's not just air flow, but also how often the unit needs to run. That said, HPLV conversion guns all vary slightly with their air requirements and whether or not they have an on-gun regulator or not. The one I've used for many years specified 40psi input with the gun regulator knocking that down to about 15 psi average. I have a new gun now and haven't set it up yet, but I'm guessing it will be a "similar" process. What you are spraying also will affect the air settings, again, depending on the specific gun. There are many folks who use a 20-30 gallon smaller compressor for spraying finishes because it's what they have and they also run on 120v, unlike most larger compressors. As long as you meet the air requirements of the gun you choose and don't mind the compressor running "frequently", it should work fine.

Jacob Atwell
04-13-2019, 11:31 AM
Appreciate all the input. Through my googling I was kind of thinking it might not be enough compressor for paint, but i thought I would ask anyways. I believe I will pick up the harbor freight gun anyways just to try it out. I just can’t seem to get a decent finish using brushes or rollers. Maybe one day I will try out one of the turbine sprayers.

Curt Harms
04-14-2019, 9:58 AM
For a 4.5 scfm flow rate it may be too low but if you want a cheap way to try it go buy one of the harbor freight guns. Google them and you’ll see lots of folks like them and they are only like $10 with a coupon. Would be a cheap way to try it out before buying a nicer sprayer.

That's how I'd go about it. The purple HF guns have a pretty good rep though HF models and sources change with the phases of the moon so it's hard to tell if the new ones are the same as the older ones that have the good reputation. A rule of thumb I remember cut can't cite a source is that consumer type guns have about a 1:3 conversion ratio, IOW they take 1 cubic foot of 24 psi air and convert it into 3 cubic feet of 8 psi air or thereabouts. That's why compressor powered guns are sometimes referred to as conversion guns. I have a Porter Cable PSH1 and run the compressor pressure at around 25 psi. Also keep in mind duty cycle of your compressor, I doubt it's rated for continuous running, probably 50% or less.

John TenEyck
04-14-2019, 3:30 PM
You won't get any better finish with a turbine than a conversion gun. The only benefit from my perspective is portability and it's all packaged together. But if you don't need portability you could buy a 60 gal new or used compressor and pretty good quality spray outfit for no more and likely less than a 4 stage Fuji turbine. With that you could spray everything from water to paint plus have a compressor capable of powering all kinds of other tools.

John

Tom M King
04-15-2019, 8:43 AM
I have a compressor similar to that, as well as some larger commercial ones, and smaller ones just for nail guns. One trouble with those low end compressors is that the regulators that come on them are pretty awful.