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There was some discussion on this on another forum but I don't think the discussion was complete.

I currently spray with a siphon feed gun and got very good results my very first try. I understand that in terms of finish off the gun, siphon feeds do a better job than HVLP conversion guns. I'm thinking of switching because of the amount of overspray that ends up all over the shop in spite of having a fan with filters in my "booth" and a whole shop air cleaner which tends to clog pretty fast when spraying. The questions are:

1) How much "worse" is the finish off the gun from an HVLP conversion gun compared to a $20 siphon feed gun?
2) Am I really going to reduce the amount of finish that ends up in the air?
3) How much extra work is there in leveling an HVLP conversion compared to siphon?
4) Are there any decent HVLP conversion guns in the under $50 range? What about <$100

If it matters, I'm spraying Stew-mac branded target USL. I also spray dye in shellac for color/bursts but could just as easily do it using color in the USL. I imagine that I'd want to stick to the jamb gun for the bursting due to a finer control.

TIA,

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Sipon feed is not the opposite of HVLP. In fact, an HVLP can be sipon feed or gravity feed.

Actually, in terms of atomization, the different style of spray guns are rated as follows, from best to worse:

1) Conversion HVLP
2) True HVLP
3) Traditional high pressure gun

1) How much "worse" is the finish off the gun from an HVLP conversion gun compared to a $20 siphon feed gun?
First you can get conversion siphon feed HVLP guns and truth is in knowing how to use HVLP as compaired to conventioal gun not the fact it is drawing from a siphon vs gravity flow

2) Am I really going to reduce the amount of finish that ends up in the air?
yes you will but more so with a true HVLP turbin system that with a converson gun

3) How much extra work is there in leveling an HVLP conversion compared to siphon?
If you learn to spray with HVLP then none and probably less than you are acustom to now dependent on your skill level. I not sure why you thought there would be more leveling with HVLP.

4) Are there any decent HVLP conversion guns in the under $50 range? What about <$100
I am sure there are but here is a small fact that many people over look. with HVLP you want warm dry air. To get this using a compressor and a conversion gun you need water traps air filter and dryer to get the best result. For less money than all of this you can buy a top shelf 3 or 4 stage turbine HVLP unit with gun that can be either gravity or siphon feed ($500+or-)

This is good - this is the exact kind of input I'm looking for. To clarify a couple things:

I'm currently using an "old school" high pressure (I guess if 40psi-ish is high) siphon feed "door jamb" gun which gives me good results. Everything I've read in the past is that those types of guns leave the smoothest finish "off the gun" so to speak and that HVLPs have the benefit of less overspray at the cost of worse finish i.e. a finish that requires more leveling. It sounds as though perhaps I'm wrong.

At this point with my current output, I simply can't justify spending $500 on a new finishing system. The question becomes will "upgrading" to a low cost HVLP conversion gun (it really doesn't mater give me a lot less mess with little or no additional post-spray finish work? If the only way to achieve that is with the $500 system, I'll stick with the old school gun until economics dictate otherwise (e.g. volume goes up to the point that potential cost savings in finish cost (the cost of the lacquer itself) and clean up time exceed the cost of the HVLP setup).

I do have a cheapie (sears brand I think) water trap on my lines and haven't had any sputtering issues with my current gun.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

It is not always true that HVLP means more orange peel. This is a wise tail that those tht have not become well experienced with HVLP tell. The adjustment technique is not the same. It takes time to get use to the difference. I can lay equally smooth finish with my HVLP system as I can with a conventional HP gun.

On the moisture issue it is not spitting that is the biggest problem with either system caused by moisture. But rather moisture in the air stream mixing with the finish media and causing major blushing. Most of the time a water trap will be fine. But if you are using the gun hours at a time a dryer is needed as well as a moisture trap. Moisture traps collect the moisture that has condensed in the air stream. A dryer dries the air stream removing moisture that has yet condensed.

That is the beauty of a turbine HVLP unit it provides dried air to the gun so that is no need for a trap or a dryer.

-

I assume that you've got an ample compressor. Based on that if you've got $400 to spend get a Sata. If you've got $150 or so get the Sharpe (now Graco, I think) Finex. Pay attention to spray nozzle size. The smaller orifice (1mm as I recall) won't allow heavier materials such as Waterborne finishes to be applied heavily enough for good flow out.
I use a Finex FX3000 for clear coats and a FX1000 for bursts, etc. I spray solvent Nitro.
For the money they're great guns. Not a Sata though...
-C

_________________
Freeborn Guitars
and home of BeauGuard©

Thanks for the info so far guys. The message I'm getting is that until I can justify around a $100 gun, I should stick with the old school gun. I did find three finex dealers nearby, perhaps I can get some detailed guidance or even try out a gun from them.

Thanks,

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I use an Asturo gun on my 24 gal compressor. I run 25 feet of hose to a moisture trap then another 25 ft to my gun. I haven't had spitting problems. The setup works very well with the Target lacquer I use. My optimal setup results in a lot of overspray, but the overspray is dry before it hits the ground and is easily swept or vacuumed up. Orange peel is a gun setup/operator issue and is completely avoidable with the correct setup and good technique.

Ken

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http://www.casperguitar.com

Very similar to stringed instruments, with spray guns, you get what you pay for. Not to be redundant, but just supportive of some good advice already given:

First off, technique is key. If you get a Sata and you don't know how to adjust the gun, you'll be frustrated.

Second, and more important that the first (because the first can be learned), is quality.

Personally, most guns under $100, you're probably at a push, quality wise. There seems to be a big gap once you go over, say, $250. In my experience, I bought enough cheap guns before I dumped cash on the Sata, because I was looking for something better. For me, a one time large purchase ($$$) would've cost less than the multiple time smaller purchases. And I STILL ended up with the large dollar purchase.

Just my $.02 (that's all I have left).

I use a gravity-fed SATA MiniJet (HVLP conversion gun). Very smooth finish, perfect control, little overspray, minimal material waste. Much nicer than my standard high pressure gun was.

I bought a Sata too. Just the gravity feed makes a big differance and the control of the Sata is great. I think mine was $300 a year ago( the guy who sold it to me took me in the back and showed me how to adjust it, great custormer service). Figure if you use it for 20 years then that's $15 a year. If you think about it, if they weren't worth the cost then why are pro painters and us here buying them and not the HF $20 guns? Because they are worth it!!!

BTW, like Mattia and Chris, mine is a Sata Minijet 3.

Again, as already stated, you cannot say enough about the difference between a siphon vs. gravity feed, standard (high pressure) vs. HVLP conversion, and low dollar vs. Sata (or other quality guns) - the latter will do you better in the long run.

I have been spraying with the same two conventional guns for 30+ years (Binks model 7 and a DeVilbiss JGA) both set up for heavy bodied enamels. Tried several HVLP conversion and turbine systems but just didn't like them. Sata makes a good gun but still not the same "feel' that I was used to. Joe White turned me onto Iwata guns a few months ago. Joe and I share a similar automotive background so I trusted his judgement and bought one. I couldn't be happier. It uses far less material (lread much much less overspray), completely atomizes the material at 3 psi and lays down a smooth wet coat that flows out as smooth as a conventional gun. They are pricy but you get what you pay for in quality tools.

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tim...
http://www.mcknightguitars.com

Man, I hate you guys. Now I'm actually considering spending the $$ on a decent gun. I was researching the SATA and found the site www.spraygunworld.com and found this: http://www.spraygunworld.com/products/A ... rCase.html which they say compares very favorably to the sata minijet. Seems like a pretty good package and it's designed for water bourn finishes which is what I'm using.

Anyone have any experience with this gun?

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I have no experience on this at all, but thought I would contribute by showing an HVLP that woodcraft has on special.

I was wondering myself the other day if this would be a good one to start off with.

Regularly $99.00 on sale for $74.00

http://www.woodcraft.com/product.aspx?ProductID=147094&FamilyID=5853

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Thanks,
Blain

http://www.ullrichguitar.com

"89.67% of all statistics are made up on the spot."

Andy, My advice for you is to buy an inexpensive spray gun. Astro makes a decent economical gun. The Kobalt (Lowes) guns look decent too. For no more than you are spraying, I don't think that an expensive gun is worth it. There are many guns out there in the $100.00 and under range that will easily do the job for you. I have Binks, Sata, Astro, Devilbis and now my favorite Iwata guns. The Iwata beats the Sata both in performance, weight and price. I was a long time Sata man in automotive but once I gave the Iwata a try, my Satas are collecting dust. I went with the W-400LV which is not a true HVLP but is a "compliant" gun. It uses much less material like the HVLP but still sprays, feels and atomizes like a conventional gun and they are light! For my burst and critical work I use the Iwata LPH80 small detail gun with a 1.0 air and fluid nozzle. This is a true HVLP and sprays great at 9 to 13 psi at the gun. I could actually do all my work with just this little gun I would just have to move a little slower.

Since you are looking for a "do all" gun, I would consider a cheaper gun with a 1.0 to 1.2 ( preferably 1.0) air cap and fluid nozzle. This is the critical part of a spray gun and will make or break the finish. For the materials that you have mentioned that you are using, the 1.0 would be more than enough for the job since you can spray with such a thin material. Remember, The magic in most finish work is not the application of the finish (with the exception of colors/bursts) The true magic is in the leveling and buffing.

For no more than you are using the spray gun, go middle road ($75.00 to $125.00) , small air cap (1.0-1.2) standard or small "detail" size are both fine, practice a bunch on scrap and keep it very clean. Find an automotive paint supply store local to you, there are likely several. Quite often if you go in and talk with them, they will have demo guns there that you can take home and try or try there at their store.

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jw ( o)===:::

cheap Plastic gun, really poor tip sets, week turbine pore air flow control. It will work in a pich but not very well. Do not buy in my opinion. Save 4 times that and get a Fuji Mini-Might 3 or 4 stage with a top notch gun included!

Thanks for the excellent input everyone. I just sprayed a couple of coats of shellac to seal things up on the guit I'm building to see how things look - I had forgotten just how ridiculous the "fog" in the shop was after spraying. I brought SWMBO down and after one look she said go ahead and buy the new gun.

Right now I'm leaning toward that kit here: http://www.spraygunworld.com/products/A ... rCase.html because it seems to come with a lot of stuff that I'd need anyway and has gotten good reviews and is Stainless. The other thought is that I've found a finex dealer nearby too and could actually go and talk to someone.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I'd spend the extra $80 and go for the Iwata LPH80 or get a Sata 90. Joe's got me interested in giving that Iwata a look.

Chris,

I'm very tempted but there is a cost issue too. The Asturo kit comes with 3 tip sizes and a regulator for $230. I have a lousy regulator but the adjustment is so coarse that I doubt it would work with an HVLP. Adding that alone is another $40. That and the Asturo has some very good reviews. If I decide to go for it, I'll definitely take some pics off the gun and do a review

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Seems like you have the idea....if you are going for a low CFM HVLP setup for guitars go with gravity feed...a pressure pot is surely nice, but there are of course issues with the finish product being in the hose (need to mix more than you need to avoid sputtering as you run out, and then recover what is in the line) and of course some pressure from the compressor is required. A siphon feed uses a LOT of pressure/CFM and you would need a very powerful compressor ($) to go that route.

Properly set up and HVLP will shoot almost as good as a properly set up high pressure gun. Since we are talking guitars (which get leveled and polished) there should be no real difference. Its when HVLPs are used for products that don't get polished that the difference can be seen. I can attest to the fact that HVLP will shoot as good if not better a finish than a high pressure gun where the pressure is too high...remember, you want to find the lowest atomization pressure.

I used a few HVLP conversion guns and was never happy with the finish so I moved to the Sata true HVLP guns.
They run between $350.00 and $450.00 ad are the very best guns I've used....and I've tried all of the major high end
brands in both HVLP and HVLP conversion formats.

I have the HVLP 2000 and 3000 model guns and both work really nicely and have SATA's air micrometer that allows
you to finely dial in the atomization of the material for very smooth application and minimum overspray and material
waste. They lay the material on the surface better than any conventional gun that I've ever used, but you really need to
get familiar with them and throw yourself into a fresh learning curve with the HVLP application and technology in mind.
It's a completely different set of conditions than in the compressor pushed gun world, but once you get your rig dialed
in, you wish you'd switched a long time ago.

Cheap guns are cheap for a reason. You pay for what you get when you're buying pro level spray gear or any other
tools for that matter. Buy right and buy once....buy wrong and be forever buying.

Regards,
Kevin Gallagher/Omega Guitars

I've decided to pull the trigger on that Asturo kit I've been mentioning. Last question is the tip sets to buy.

Joe recommended a 1.0mm tip. The choices for the kits are:

"wood master" at 1.0, 1.2, 1.5
industrial thin at 0.8, 1.0, 1.2.
(there's a couple other choices on the website but these seem to be the most interesting)

I'm thinking it might be best to go with the industrial thin with the 0.8mm tip as I often spray my color in a 1lb cut of shellac. Does this sound like the rite choice or will 1lb shellac spray fine from 1.0mm? If it can, I'll go with the wood master sizes as it has some larger sizes too.

TIA

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Andy, if you want the gun to be able to handle bursts, the finer the atomization, the better. If you normally spray the rest of your products thin, the 1.0 will be able to handle that as well.

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jw ( o)===:::