Recommended Spray Gun

[Wayne Copeland]

Good morning fellow woodworkers. I am somewhat new to the site and have a question in which I hope you finishing experts can help me with. I have a white oak dining room table, white oak coffee table and two large cherry wood interior doors I need to finish in the next few weeks. I usually apply shellac and/or varnish as a final finish with a brush, however, I am about to start building a spray booth in a portable building and want to know what kind of spray gun you all recommend for these and other water bourne type finishes. I looked on the site menu and could not find a thread to this question, so please excuse the redundency if it is posted somewhere else. Thanks for your thoughts on this matter.

[John TenEyck]

There are several choices you need to sort through, but most folks either go with a compressor driven HVLP conversion gun or a turbine unit. Each does a good job when matched with the finish you plan to spray. If you already own a large compressor, a conversion gun is usually cheaper. If you don't, or you need portability, you might prefer a turbine unit. I use low cost HVLP conversion guns; none of them cost more than $40 and am very happy with the results I get. Even the HF gun I bought on sale for $10 sprays shellac and low viscosity finishes beautifully. You can spend a lot on a spray outfit, but it's not required to get good results. You, the operator, are the most important piece of the puzzle.

In order to spray both low and high viscosity finishes you need more than one gun, or a gun which you can change the needle and orifice. With my HVLP conversion guns, I use a gun with a 1.4 mm tip to spray shellac, and another gun with a 1.8 mm tip to spray most water borne finishes. Most paints require an even larger orifice. There are many good sources for reading how to match the gun type and required orifice size vs. product viscosity, and a quick Google search will give you several free references.

You mentioned varnish as something you'd like to spray. If you meant solvent based varnish, I would highly recommend against that. First, you would need a spray booth designed to handle solvent products, including an explosion proof fan and lighting. Just as important, when you spray a solvent based varnish the droplets do not dry very quickly, and they will form a sticky, crusty mess on whatever they fall on. The good news is, there's no reason to spray those products; there are many fine water borne products that can handle just about any application you need.

John

[Jim Becker]

John has offered some good advice. I personally use a Wagner HPLV conversion gun with a compressor. (I actually have two of them; one with on-gun cup and one with a remote cup) Regardless of what you choose, if you opt for a conversion gun to be used with a compressor, be sure to note what the required SCFM is ... you do not want your compressor running constantly to keep up with the air requirements of the gun. You'll also want a regulator to step down the input pressure to about 40 psi...the regulator on the gun then gets set to a lower value. Mine is running at 15 psi which works well for my particular gun.

And yea...just say no to spraying oil based varnish...sticky, sticky mess!

[Kent A Bathurst]

J-10 & Jim - just as a point of reference for the uninitiated.........

On the compressor to run the conversion gun:

1. What compressor are you using today?
2. Assume blank piece of paper; You are going to buy a new compressor to drive your spray activities only. What would you buy?

I am not asking for a specific recommendation on brands, per se - I just want to get an idea of what thie critter looks like: "X cfm; Y psi; looks like the I-R Z-hp with the Q-gal tank".


Thanks

Kent

[John TenEyck]

Kent, I have a 60 gal single stage compressor. It puts out about 7 CFM at 90 psi and around 10 CFM at 40 psi. That will run all but very large spray guns. I paid $300 for it used and have been using it for 5 years now with no problems. Start with the gun and see how many CFM it requires. Then find a compressor with at least that much output plus a safety margin of 25% or more. As with many things, bigger IS better.

John

[Jim Becker]

Kent, I wouldn't go out and purchase any compressor for use with an HVLP conversion gun that was less than the capability of at least the IR Garage Mate. (25 gallon) You can very often use a lesser compressor, but for best results you want something capable of delivering air with at least the required SCFM and the larger the tank, the less it's going to be running during the spraying. I personally use an IR 60 gallon 3hp compressor in my shop. I don't say this to discourage folks from anything, but it's part of the "do I buy a turbine system with a gun or an HVLP conversion gun to use with a compressor, either one I already have or one I'm willing to buy that's up to the task". Small compressors that many folks have are great for pneumatic tools like nailers, but some tools, like spray guns and pneumatic sanders have stiffer requirements. This is all related to why setups like the very attractively priced Earlex turbines have gotten pretty popular...

[Kent A Bathurst]

Guys - got it; thanks. Requirements are clear. Conscise, on-point repiles are always welcomed.

OTOH - you fell a bit short of a stand-alone "plausible excuse" for the venrable I-R T30, so from that angle I am a bit disappointed in the responses, but they were accurate and helpful..

I guess if I throw the Mirka sander into the equation, I will come closer to excuse-ing my way there, no? And, there are always incomprehensible nuggets from the woodworking shop lexicon that I can drag out to salt the mine.

Or, I can discard a fool's dream and just follow the Stones: "You can't always get what you want, but if you try, sometimes you'll get what you need".

[Jim Becker]

A pneumatic sander brings you into a whole different world when it comes to compressors as compared to spray finishes. For the latter, the bigger compressor tank mostly brings less run time as long as the SCFM requirements meet the gun's minimum. For the former...you need a TON of air period just to run the tool! So yea...having that Mirka pneumatic sander "accidentally fall into your tool box is a great excuse to getting that compressor you REALLY want. LOL

[Wayne Copeland]

Thanks for all the responses and the great information. After doing a considerable amount of research on various spray guns, I had pretty much made my mind up on the Wagner conversion gun. I have a 2hp comp that is rated at 6.5 cfm @40 psi. I finally found some internet product information on the Wagner and it stated the Wagner conversion gun required 15 cfm. I called Gleem and spoke with Micheal, who incidently seemed to be not too interested in talking to me about the Wagner, but did state the Wagner required 1.5 hp compressor with 6 gallon tank. When I told him about the information I had discovered elsewhere, he said it was "old information" and my 20 gallon 2hp comp. would be more than adequate. This left me a little less than satisfied with him, his "expert" opinion and with Gleem in particular. Are there other brands of guns you would recommend that are not air hogs? I do not want to spend the extra money for a turbine unit, nor do I want to invest in a larger compressor due to space constraints. Other than a couple of foreign made HVLP guns I found costing substantially more than the Wagner, most others I reviewed also have high cfm air requirements. Thanks again for your time and comments. Wayne

[John TenEyck]

You may find it hard to believe but the low cost Harbor Freight HVLP gun will spray very well with 6.5 CFM at 40 psi. http://www.harborfreight.com/20-oz-h...tor-69705.html It comes with a 1.4 mm orifice and it sprays shellac and other < 45 second #4 Ford viscosity finishes beautifully. I have never needed more than 35 psi and usually run below 30 psi; for shellac it's more like 20 psi. That gun costs $30 with a mini-regulator, and it's often on sale or you can use a 20% off coupon. Go buy one. You won't regret it. It will get you into the game and you can always buy a higher quality gun later and use the HF one for stains, etc. The HF box will say that you need 45 psi or something like that. You don't. It runs great under the conditions I stated above. It does not have stainless internals but I've had no trouble with it for 2 years of spraying shellac and water borne finishes. I just clean it out and the end of the day and spray out any residual water.

John

[Mike Henderson]

Regarding how big of a compressor you need, a lot depends on how big a project you're going to spray. If you do small jobs, or if you can break the job down into small sections, you can use a small compressor. I have a 1HP compressor - don't remember how big the tank is - and I can do furniture jobs easily.

I've even done a built in cabinet top in place with a pancake compressor. You just have to go slow and let the compressor catch up (and put that noisy thing outside).

Mike

[Jim Becker]

Mike is correct...the SCFM insures that your compressor can produce enough air, but the tank is what governs how long you can spray before the compressor has to kick back on and run. If your projects are such that you're not spraying constantly for a long time, you can get away with a smaller compressor system than you would find pleasing if you were spraying large projects and pushing a lot of finish out in a short period of time.

[Dave Rose]

Wayne, take a look at the C.A.Technologies guns. I've been using the 'X-LOW AIR' version of the Lynx 100H for a few years now and I'm very happy with the finish that it can produce compared to my $600 Sata.

[Wayne Copeland]

Thank you all for your suggestions. I appreciate the time and effort you took to provide me with this information.