compressor for HVLP

Re: compressor for HVLP

mdclor

>Bill,

Talk with Jeff Jewett at homesteadfinishing.com to see what he suggests. Then let us know what you decide.

Happy shopping!

Merle

Re: compressor for HVLP

billfrommich

>mdclor,

Thanks for the reference to a very interesting and informative website. I am familiar with Jeff's book(s) but didn't know about the site.

Re: compressor for HVLP

Paul Dwight

>Eight gallon tanks will mean the compressor will cycle on very frequently -- on large projects it might run almost continuously. The pump might stand up to it, but it wouldn't be much fun to be in the workshop with the thing running continuously. The noise alone would keep me away from a unit with eight gallon tanks.

If you're willing to stop spraying while the tanks recharge, the 8-gallon machine ought to provide results that are essentially equal to the larger machine. The difference should be convenience (waiting for the pump to catch up) and noise.

The bigger tank of the larger unit might provide enough capacity for other air tools in the future -- sanders and what not.

If you don't need portability, I'd go for the larger unit in a heart beat.

Good luck! -- Paul

Re: compressor for HVLP

billfrommich

>I had discounted the noise issue because I assumed (not from my own experience but from the testimony of others) that compressors with belt drive, induction motors, and oil lubricated pumps are bearable. On second thought I guess I would prefer to paint in a relatively silent environment.

What I don't understand is if and why you would have to stop spraying while the pump is cycling if the pump is capable of supplying the required CFM while operating at (and rated for) a 100% duty cycle. It seems like you could almost go "tankless" - the main purpose of the small tanks would be to provide some buffer against the rapid, pump cycle induced, pressure pulsations in the air line, rather than to provide a reserve capacity because the pump is "falling behind" (which it wouldn't be, if it indeed can supply the required CFM).

Re: compressor for HVLP

Paul Dwight

>I suppose the issue is whether the pump can actually keep up with the CFM requirements of the gun. My single-stage 3HP Porter Cable with a 30-gallon tank doesn't keep up with my gun. If I continue to spray once the pump cycles on, the pressure drops and the gun can't atomize the finish properly.

A two-stage compressor might keep up with an HVLP gun, I guess. I seriously doubt whether any single-stage compressor would keep up.

As a point of reference, if I'm spraying more-or-less continuously my compressor cycles on every 3-4 minutes -- and that's with a 30-gallon tank.

Good luck! -- Paul

Re: compressor for HVLP

NickB

>The other issue, I think, is heat and moisture. As it's compressed, the air gets pretty warm (so it can hold a fair amount of water). If you have a big tank, there is more of a chance for the air to cool and condense out the excess moisture (of course, you'll probably want to have an dryer on your line anyway, but there's not much to be done about the heat). That said, I have a small conversion HVLP gun, which my 12 gal. compressor can just handle (I rarely have to wait for the compressor to catch up, but it does run a fair bit) and spray mostly waterbornes, and haven't had any problem in that department.

My take on this issue in general is that there are 3 kinds of compressors- (1) stationary (60 or 80 gal) that can handle just about anything (at least if they're 2-stage), (2) semi-portable (you can move them, but they're not fun to move up stairs, etc.) that are good for framing and might be able to handle a HVLP conversion gun, and (3) very portable (1 or 2 gal. tank and less than 1 hp) that are great for smaller nailers (15 ga. and smaller). I have types 2 and 3, as they were originally purchased for framing (type 2) and trim work (type 3, after I got tired of schlepping the bigger compressor). But if you're not going to need to move it on a regular basis, go with the big stationary compressor (and remember to drain the water out of the bottom of the tank regularly-cuts down on the risk of tank failure).

Just my $0.02, and worth every bit you paid for it,

Nick