Another air compressor question

[wens]

Hi all, I have read the previous posts that I could find. I've got a Harbor Freight HVLP spray gun (this one), and am planning on getting a small air compressor, probably this one. I know it's kind of underpowered but I think it will be OK for spraying some raku patinas or terra sig, based on reviews. I don't want to make a huge investment in something I may not use that much. I am trying to figure out the hose and fittings needs. The sprayer recommends a hose of 1/2 " internal diameter, but it looks like I need to get a 3/8" hose with 1/4 inch fittings? Does anyone have advice on hose diameter? How long a hose do you use? I can plug the compressor in my kiln shed and spray outside, but don't want to get too long a hose. I can call Harbor Freight to ask about the fittings, but it's confusing. Something like this with a 3/8" hose?

TIA, Robin

[JohnnyK]

Welcome to the forum, Robin...All of what you have listed here will be more than adequate for what you plan to do. 4+ cfm @ 90 PSI of air pressure with 150 PSI max pressure with 100 feet of 3/8" hose will easily handle your requirements. I've run roofing guns with more hose and less pressure, and sprayed finishing lacquer on cabinets at around 35 psi... With the HVLP gun, you are only going to run it at about 20 PSI for the glaze or terra sig. Make your purchase and have fun!

[Min]

That small a compressor is probably going to be running pretty much non stop to keep up with spraying glazes, depending on how long you plan on spraying each minute. A possible workaround with a smaller compressor, if needed, is to use a air pig / secondary air tank. Air sprayers use a lot of cubic feet per minute of air therefore shorter bursts are fine but for continual use it's going to struggle. I use a vertical Atlas Copco compressor, stands close to 6' overall, it still comes on about every 10-15 minutes or so when I'm spraying.

3/8" hose would be best, the 1/2" inside diameter in the gun specs is misleading, most hoses are either 3/8 or 1/4". Just ask HF for couplers / adapters as necessary that fit the hose you are buying and the gun. You want to get a flexible hose if you can, cheaper hoses are stiff and can fight you. As well as wearing a P100 mask I'ld strongly suggest wearing some good hearing protection while spraying glazes.

[Mark C.]

A few notes -I really like the non oil models which yours is. But thats only for the smaller types. Larger needs oil. As to the couplers there are two styles-harbor frieght sells one style (the cheapest) and the other is at hardware /big box and they do not couple together so know this going in.

I have a small 2 gallon tank model that is super quiet and love it. I'm not a fan of some of Harbor Frieght tools-so check on the reviews-there are many brands in this price range

I would get a brand with good reviews 

[liambesaw]

I have a compressor that size for my hvlp gravity feed sprayer.  And yes, it's running the whole time, is very loud, and gets very hot, so I have to let it rest every 15 minutes or so to avoid thermal shutoff.  

It works but it's not ideal.

[wens]

Thanks all! I didn't want to shell out for a large compressor that may get little use, so am fine with it running constantly and waiting for it to catch up. I'm such a slow potter and don't finish that many pieces, and I'll need to practice with the sprayer and see if I like the effects.  It should be more noticeable for terra sig, where I can't keep track of the number of times I've brushed over a section of the pot.  If it turns out I do a lot more glaze spraying, I'll think about getting a more expensive compressor then, but the oil-free ones do seem nicer, if loud.

[CactusPots]

As for using the compressor,  I'm a big fan of blasting every pot before glazing.  It's a dusty environment between the clay dust and the natural place I live.