Spray gun questions

[Brookside]

I've been sitting here for a couple of weeks, not finishing my mandolin because I don't know squat about spray guns. Seems like a simple enough matter. A fella needs a spay gun, he buys one, and finishes his mando.

I was planning on applying the stain by hand and spraying on the laquer. I see one stinking spray gun for sale at Stew-mac. (cept for a little airbrush thingy) I've searched the forums here and found someone saying it's not a bad one. Another builder says Sata is the only way to go. I see that Sata makes about a hunnerd different spray guns. And maybe I should be looking at little airbrush thingies too since I'm reading that hand applying stain can be tricky for an amateur.

My only questions are, what spray gun do you use for applying laquer? What would you recommend for an amateur?
Same questions for the little airbrush do-hicky. (if you use them at all)

Thanks everyone.

[mandoJeremy]

Get the Sata Mini-Jet. You will not regret it at all.

[John Bertotti]

I emailed a paint shop on the net, gleem paint, and asked for their recommendations. I see they carry wagner equipment they recommened the HVLP conversion gun. It will run on a 2hp compressor but an article I read said for continuous spaying something with a bigger tank would be better. The man who wrote the article used a 2hp 6 gallon pan cake compressor. I still haven't had a chance to find one and try it. Maybe someone here has. John

[sunburst]

I use an old Sharp model 90. You can't get them anymore. They were sold for painting cars and were medium priced. They were sort of like Sure SM57 and 58 microphones. Got the job done, little trouble, tough, but not fancy.
I've used two or three different HVLP systems and two different Binks conventional type guns. None was clearly any better than another.

I recomend any fairly small and comfortable spray gun that is meant for cars. Get one that feels comfortable and you'll do a better job with it. Any of them will do a good job, with the possible exception of the real cheapies, so go for comfort, parts availability, and someone knowlegable to buy it from. It's not important if it's gravity feed or siphon feed, so don't let the salesperson pull your leg. Presure feed is my favorite, but it's not too practicle for a limited budget small shop.

HVLP will not necessarily give you a better finish than conventional, finish quality is dependant on a good tip/nozzel combination, and unless you're spraying several gallons per week you'll never pay for the difference in cost with material savings.

As for air brushes, I only use them for touch-up, repair, some staining, and finishing small parts. I've only used two brands, Badger and Pasch. Of the two I prefer the Pasch. Here again, get one thats comfortable. They all work, with the possible exception of the real cheapies.

By the way, I sprayed instruments 2 or 3 times a week for over 6 years, so this is more practical knowledge than scientific knowledge. Hope it helps.

[Bluemando]

I did get the smaller airbrush from stew-mac, and I like it a lot. It came in very handy on #1. I did, however, come to regret my decision to but a cheap gun from wally world to spray my clear. I think for #2 I will definately break down and buy the bigger badger from stew-mac.

[mandoJeremy]

I was only recommending the Sata Mini-Jet because it is smaller, not because it is HPLV. #I can attest to the fact you don't use as much material with them and you will get a slicker finish before buffing with one of them. #I actually prefer the Jet 90 but it is a full size spray gun. #I worked in paint stores and then body shops for years and the Sata is THE standard. #I do have an email from Hans Brentrup thanking me for the advice on the Sata's and he had noticed a difference on the first one he sprayed with it. #Just ask him for advice about them.

[John Bertotti]

I just checked out the sata on the web. Man they do look nice. I will have to try one of them to. John

[Luthier]

I would like to chime in here, if I may. #Finishing is as much an art of building as the construction is. #A finish will make or break an instrument. #I would suggest practicing on a few scraps of wood before your final undertaking of the mandolin itself. #I have seen instruments that were wonderfu in sound but the poor finish took away from the total appeal. # # # Don(Enter key problems again)

[Hans]

Sata Mini-jet...yes indeed! You can find them on the web for about $200.

[Lynn Dudenbostel]

Sata, DeVilbiss, Sharp.... all good guns. But one thing you absolutely want to make sure of, is to get the proper air cap and needle assembly for the viscosity you are spraying. Ideally, a viscosity cup should be used to determine the proper thinning of your lacquer, but if you find a really knowlegable saleperson, tell them what you are spraying, they should be able to match up an air cap and needle to give you really good results. The spray gun is only part of it..... proper components for the spray gun make it or break it!

Lynn

[Jim Hilburn]

I use conventional guns, an old Binks model 15 for stain and a Sharpe 975 for lacquer. It's never really a problem, but even here in dry Colorado, the compressor gets moisture in it, and even though I have some big traps on the air line, I do detect some moisture in the air sometimes.
My question to those with HPLV equipment. Do you still have moisture problems?

[mandoJeremy]

On most clearcoats I would suggest a 1.4mm needle.

[sunburst]

My question to those with HPLV equipment. Do you still have moisture problems?
I don't know about the conversion systems, but the ones I used heated the air as I sprayed. This kept any liquid water from getting to the tip, but also required that I adjust to changing viscosity as I continued to spray.
A good air drier will help much. They aren't terribly expensive and if you're spraying a lot with a conventional compressor you need one.

I don't recomend against viscosity meters and such scientific stuff, I'm sure they help and I could learn from them, but I just watch the material run and drip off of my stir stick. I can tell when it's about right. If it's a little different from time to time, I have no trouble adjusting my technique. This is ability aquired through experience, I suppose, and if I had really known what I was doing when I started I would have, and probably should have used gadgets to develop my intuition.

[Brookside]

This is a great wealth of information on the subject. It still amazes me that I can get advice from my heros in mandolin building. Thanks to all who took the time to respond. I'm back on track.

[John Bertotti]

Does sata have a set up hvlp system? What size compressor do you need for the mini jet? It is incredible to see, day after day, the diverse wealth of info in the members here. John

[Hans]

The nice thing about HVLP guns is that you don't need much pressure. Sata recommends no more than 37# at the gun. You need a pressure guage at the gun. I find that I'm shooting at about 18 #. A #while back I bought an Iwata airbrush for about $150. #Excellent airbrush. BTW, I was told that turbine HVLP systems require very good air filtration, something that the cheaper ones don't have.

[John Bertotti]

Thanks for the info I should have been more specific. I was wondering not about the pressuer but the cfm airflow.I am looking at the craftsman compressors. either the 2hp 6gallon, the 3hp 15 gallon or the 6hp 30gallon. The pancake will run my paasche or vega just fine but a larger gun may not be as forgiving. I love those Iwata airbrushes, about five years ago I was adding a dual action to my set up and looks at the Iwata but wound up buying a Vega. It has been a great little air brush but I wish I had the Iwata. At the time the vega responded to my untraind fingers better. My first brush was only single action and it was a bit of a change. Iwata had some nice gravity feed guns do they compare with the Sata? Thanks All, Brookside nice thread to start. John

[Jim Hilburn]

I have a 5hp 20 gal.,but I used to use a much smaller one.For mandolins and guitars, this is plenty. It's when you try to paint the old Plymouth that you'd get into trouble.

[John Bertotti]

I found the sata mini jet info on their site. It claims 3cfm and 29psi air consumption. John