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And OMGaaaaah this is the most confusing thing I've gone through in a long time. I've heard people mention that they get good results with the Harbor Freight El Cheapo HPLV guns so I was looking at those. But I was also looking at some more expense Fuji and Devilbliss guns.

The problem is the hose for my turbine is 3/4in and all the guns seem to have a 1/4in inlet and there apparently is no adapter to make the connection. So I'm guessing you plain and simply cannot use a gun like this on a turbine system?



Then I researched "turbine spray guns" and found this one: https://kebco.co/en/m-model/1957-7002g- ... 7002g.html

Which has the same inlet to connect to my turbine hose. So is that the key then? Are turbine spray guns just totally different than HPLV spray guns? I have not been ably to find a Turbine gun that looks like it could do any detail work like touchups or bursts and I'd like to have that control. The turbine guns seem to be for spraying large things like cars or even walls with paint. But I have read up on many luthiers who use them to spray Nitro or water base finishes. Is there a gun that fits a trubine hose out there that is luthier recommended and not $600 bucks?

Hi, the terminology can be confusing. A turbine system is the turbine, the hose and the gun. The turbine system is HVLP (high volume low pressure). The gun in the image is also HVLP but made for an air compressor driven system, not a turbine. Two different technologies, with different hoses, guns and pressure sources.

If at all possible, go in person to a vendor of hvlp systems and see where that conversation goes. We who respond are doing so with little-to-no information and our scatter of well-intentioned comments may make your head spin. at best and misinform you at worst.

A whole lot of time and cash can be wasted using piecemeal comments and opinions.

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Peter Havriluk

The best shortcut to solving this problem would be to talk to or correspond with Jeff Jewitt at Homestead Finishing. He is the expert on spray systems and stocks and sells the equipment you will need. He gave me good advice and sold me the gun I am using now. I was prepared to buy the top of the line high dollar Fuji system. Based on my experiences, he recommended that I stay with the compressor and just replace my gun. He was right and I am getting very good results.

What turbine do you have?

I have a Fuji T-series gun and a Fuji turbine and have been happy with its performance spraying nitro. Needle size is important.


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It's a Harbor Freight turbine. Avanti? I think something like that. the gun that came with it has a 1.3 needle. I sprayed a panel last night and it actually came out quite well but the spray pattern is huge and doesn't have much control for burst or touch up. Does the Fuji gun have spray pattern control? Like you can spray a 4in swath?

Talk to Jeff Jewitt of Homestead Finishes, I got my gun from him.

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HVLP is high volume/low pressure... these guns push a very high volume of air at very low pressure (2-10 psi), with that low pressure air source either a turbine (think gloried vacuum cleaner with intake and exhaust reversed) or by converting the high pressure (40-90 psi) air flow from a compressor to a lower pressure, higher volume flow.

The terms in common use are:

1) Conventional spray gun (one with low transfer efficiency of what you are spraying, and usually using a compressor for high pressure air source)

2) HVLP turbine gun (a higher transfer efficiency spray gun connected to an air turbine with a 3/4" low pressure line), and

3) HVLP conversion gun (a spray gun designed to take high pressure air from a compressor and convert it to lower pressure/higher volume for increased transfer efficiency

Bottom line on compatibility: A conventional gun and an HVLP conversion gun work with compressors, while the turbine needs a turbine.

For decades, turbine guns were specialty tools for handling low viscosity, clear finishes like shellac, lacquer, etc. without the need for a large, heavy compressor, long hoses, and air flow dryers (a turbine ALWAYS provides clean, dry, hot air; a compressor provides cold to at best warm, damp, and relatively dirty air, so needs a refrigerate or desiccant dryer as well as a good filtration system). The downside to turbine systems was the gun - usually la clunky cup system with at best rudimentary air and material controls. That changed with Big Brother high and low-VOC coating transfer mandates and the trend towards taking the tool to the job site versus making the customer bring the job to the shop.

Fuji (a Toronto, Canada based designer/importer of turbine and conversion systems) began offering 4 and 5 stage systems which could handle higher viscosity coatings as well as offered gravity and cup guns with the fan shaping capability of conventional and HVLP conversion guns. The T-75G is the current iteration of the gravity gun and is the one Greenridge still runs 3-4 of at any given time. A few things:

- Any dedicated turbine gun will run off anyone else's turbine air source, so a 3, 4, or 5 stage turbine (each stage provides 1.5 to 2 psi at the spray tip... higher tip pressure means more capability to properly atomize thicker finishes) will handle most guitar shop finishing chores. Stay away from cheap two-stage systems - they can barely atomize thinned finishes like 1.5 lb cut shellace, and would have never handled the 70-30 thinned lacquer mixes we used for top-coats reliably.

- More stages means greater ability to spray finishes without significant thinning, but means more cost and more noise (pay for the quieter version of the turbine - money well spent)

- Most cup and gravity turbine guns now sold - even the cheapies - offer fan control and at least inline ball valve air volume control

- You cannot use a turbine gun with a conventional compressor, and the low pressure feed from a turbine will not work well with a a conversion or conventional gun. If the hoses do not mate, consider it a sign from the heavens that things were not meant to be.

My experience: we used all three guns and both air sources at Greenridge, and I have a four stage turbine system from Fuji at present. With a 7.5 hp Quincy four cylinder compressor in the shop with cleaner/dryers inline, we used everything from high-end Japanese conversion and conventional guns (2k and 3k finishes) to cheap Harbor Freight $10 throw-aways (primers/waterbased) and $15 jam guns (gold-top and other metal-in-lacquer jobs). The compressor system was a) very expensive, b) relatively maintenance-intensive, c) subject to some strict humidity and temp limits, and d) anything but portable (with compressor weighing in at something like 350 lbs and requiring a truck or large SUV to transport). The turbine system was a) small, b) light, c) ultra-reliable, d) happy to provide warm, dry, clean air to allow spraying in higher humidity and lower temp conditions.

Re: guns: A good gun costs, with the Fuji T-75G about half of what the SATA conversion guns ran, but still 5x-15x what a serviceable Harbor Freight conversion gun might run. In the time I was at Greenridge on a regular basis, we retired one of the T-75G guns due to excessive wear... the gun was from the first production run and could not be economically repaired. During the same time period, we rebuilt all of the SATA and Iwata guns at least once, despite usage limited to perhaps 5% of all finishing chores.

Finally summary: suck it up and buy a Fuji T-75G if you want turbine technology. For conversions systems, get a minimum 5 hp/60 gallon compressor, good filter system, and run at least one desiccant dryer inline.

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Woodie just said all there is to say! I have the T75G too and find it very good and control over both fan pattern/size and fluid volume is good and you can shut it way down for sneaking up on things when bursting, or let ‘er rip and paint a barn door.

I only use mine for nitro and shellac and find it behaves well with a 1.0mm needle.

As Woodie pointed out too, and critically for my climate, the warm air from the turbine plus 10% retarder let’s me spray nitro above 65% RH without blushing which makes it really the only fit-for-purpose system for this part of the world.

Thanks for clearing that up Woodie, much obliged.

Here is another article that explains some of the differences between "conventional" spray guns and HVLP types:
https://www.ehow.com/info_8098555_diffe ... -guns.html

I still use a small conventional high pressure gun. Since it is a small "jamb gun" it doesn't take a lot of air and for spraying small items (guitars and such) it can be used with a small portable pancake compressor. You can reduce the pressure to reduce the overspray with a reduction in the atomization, or increase it and get finer droplets, more overspray, and less finish where you want it. A better gun will cost more, give you a smoother finish (less orange peel) and waste less finish. Because I spray things laying flat I can use a cheap jamb gun (similar to this one: https://www.ebay.com/itm/374985880705?h ... BMnLXasedi ) , spray a heavy coat at a lower pressure (less overspray - better transfer rate) and have it flow out reasonably well. Since I am sanding and buffing the finish some orange peel can be tolerated. I'm spraying solvent based lacquer which is a low viscosity finish.
I have the inexpensive HF turbine gun - it's great for spraying deck furniture and sealer on decks. It puts out a lot of material in a short amount of time. They do have more expensive models, but I have no experience using them.

I no longer use my fuji's I like divilbiss with the D cup but will agree they are good guns. Pittsburgh spray equipment is a good supplier. They are not cheap but good guns aren't. Fuji are designed for being easy to maintain and parts are easy to find.

https://pittsburghsprayequip.com/pages/ ... pray%20gun

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I ended up going with a Fuji gun, thanks for all the tips.




What compressor is that? It looks like the Craftsman pancake compressor that I have but I would not have thought that was good enough for spraying Nitro. Do you use a regulator at the air inlet?

I'm no spray finishing expert (I'm the opposite), but from my limited experience, I know you can use a small compressor if you pair it with a gun that requires very little air. The Iwata lph80 is an example. However, you may need to also separately dry and clean the air produced by the small compressor. I had to. I lucked into a refrigerated air dryer at a decent price, and I use a decent oil/water filter in the line, too. None of this is cheap. But, I have clean, dry air for finishing.