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Hi Guys,

I'm looking at spray equipment. I have no prior experience with the equipment and wonder if I could get some recommendations. I tried to do a search to find a similar thread and if it's there, I didn't find it.
I have limited space, so I don't want a large tank, but from what I'm reading, you may not get good continuous flow with a tank under 20 - 30 gallons.
I also looked at reviews of paint sprayers like the Earlex 5500 hvlp....would that atomize sufficiently and give a good finish?
As always, I appreciate the advise! Thanks, Beth

Hi Beth - I use a Wagner HVLP conversion sprayer with a 2hp 4 gallon tank. I haven't used it for a guitar, but this is the set-up that I use for staining and finishing kitchen cabinets, so there would be no problem spraying a guitar.

Alex

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Beth,

I have the Earlex 5500 and find it to be a wonderful machine. it is easy to use and lays down a good finish. But keep my recommendation in perspective, this is the only sprayer I have used since high school shop back in the days LONG before there even was such a thing as HPLV sprayers.

I started this thread a couple of months ago

viewtopic.php?f=10101&t=32762

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

There are so many spray units . You need to find an informed person as this is all about matching nozzles to spray material you are using . I have an HVLP unit that runs off an air compressor . You can also get turbine units. AC units will need a good water separator to avoid contaminating your material .
HVLP units are good but work differently from pressure units . I have a sata unit and this one that surpised me . It worked better than I thought it should .
http://www.grizzly.com/products/Profess ... -4mm/H7669
I spray Nitro and vinyl sealer with this. If you use water you may need another nozzle for different material .

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
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Hi Beth
I have the Earlex and finish my guitars with EM6000.
The results are excellent and I wouldn't hesitate to recommend it.
Mat

Thanks for the responses, all. Kevin, I read your linked thread .....guess I used the wrong key words in my search
I think I will go with a turbine. I have a hobby compressor, and won't use a big compressor for anything but spraying instruments. My initial practice, though is going to be refinishing the kitchen cabinets, so I can make my mistakes on something I care less about
Happy Sunday! Beth

So, after all your helpful input, I have decided to go with the Earlex hv 5500, and use Target coatings sealer and EM 6000 (by the way, Target no longer offers their Blonde WB Shellac...just Amber, Garnet and Red Oak).
I have heard discussion of the final thickness of the finish in the neighborhood of 4 mils. Those of you who have or do measure this, do you use a wet mil gauge? Do the impressions go away on their own?
Thanks, Beth

Beth,

What finish are you planning on spraying? If you're thinking nitro, equally important to the question of the sprayer is the spark - proof exhaust, a very good respirator, etc. Water based doesn't need a spark-proof exhaust but you still need a good respirator, etc.

How many guitars will you finish, where will you be spraying, etc. That might give some more detail so that the experts here ( I don't consider myself in that category ) can provide guidance.

Corky,
I will spray Target's waterborne products (sealer and lacquer). I will definitely wear a respirator and eye shield. I won't spray Nitro because I don't have a safe setup for it.

I am planning a future cocobolo build....do I have to worry about using a waterborne finish on oily wood? I read that you should rub the surfaces to be glued with acetone right before gluing. Does the wood need to be treated in any way before applying the sanding sealer (or do I need to use another sealer like shellac instead)?

I have been zpoxy porefilling ala Todd Stock...can I continue this under the Target products, or do I need to change fillers?

Thanks again!

Fair enough, Beth. I'm also a waterborne guy. Have been using KTM 9 but will use Target EM6000 on the next due to availability issues with the KTM.

As for spray setup, I've got a compressor and an HVLP gun, both from Home Depot. Not particularly fancy stuff. And they both work OK, although I've had to think the KTM9 with a bit of DA to get it to flow properly. Probably user error as much as anything.

I don't think the acetone is a good idea, especially on a wood like coco that bleeds. Others, (Todd, perhaps) have suggested that as long as you glue those oily woods soon after planing or sanding, you'll have no problem. I don't think you'll have any problem with the waterborne finish, expecially if you use the epxy as pore finisher, etc. Some use sanding sealer in between. I generally use a coat of shellac in between.

I haven't worked with coco but there are a lot of discussions on the topic of Coco bleeding, so it's worth a look on those. I seem to remember some talking about sealing the bindings with shellac prior to prevent bleeding.

I don't use waterbase because I have never found any that satisfied me. It's either nitro or 2K poly...

I bought a Taiwanese clone of the Iwata Y-101 spray gun last year for a les paul custom restoration, really liked it because it sprays quite nicely and wasn't so difficult to use like the cheaper Chinese clones. The seller offered 5 different tip sizes (1.0, 1.2, 1.3, 1.5, 1.8) and I took 1.3 to allow me to spray lacquer and bursts. It does both quite well. It was only about 50 dollars.

I had bought a cheap spray gun from ebay a while ago and had to throw it out after a few projects because the body was coated in a paint that would be dissolved by the lacquer, leading to red stuff in the paint. The paint also affected its fit and finish because the inside was also coated in this paint, leading to leaks.

You don't have to buy the best spray gun in the world, but you do need to make sure they're solidly constructed so that it would last, like stainless steel cup (rather than plastic that can't stand up to repeated use of solvent based paint), bare metal body, good tolerance, etc.

Test your spray pattern before spraying anything critical like bursts. For lacquer spray pattern isn't as critical but to avoid orange peel, it's still important.

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A wet mil gauge may be useful, but.........it's not the whole picture. The impressions won't usually go away, so use one on scrap, to determine how much you're spraying. The solids content of the finish will determine how much it shrinks, so 3 wet mils would end up being alot less than 3 mils. I don't use waterbornes, but I've read about people using a BUNCH of coats. (like 15?) It doesn't seem like that would be necessary for a thin finish, even it if does shrink alot, but I don't use it. Joe White recommended spraying test panels of glass to determine how thick a finish builds. I also measure the thickness of the top, and a specified location inside the sound hole. This allows me to monitor how much finish I'm applying, as well as how much I'm sanding off. You need to be consistant with the applicaiton of the finish, over the entire body, as well as when sanding. You can't sand a bunch in one spot, just like you can't spray a bunch of finish in one spot.

Personally, I believe a finish over 5 mils is going to start hurting the tone. I also believe a finish under 3 mils probably isn't going to offer enough protection.............so my target final film thickness is 4 mils.

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Todd, I reviewed the XPC mini mite 3 and it appears there are two options...one with siphon feed and the other a gravity gun. Their specs appear otherwise the same. Do you have a preference? I have small hands, and wonder if a gravity feed would be easier to hold, but don't know if that is true or if the type of gun makes a functional difference.

Woody, thanks for the thickness clarification.

Have a great weekend , guys! Beth

That's great info, Todd. I was going to spray waterborne lacquer because I don't have a spray booth, and also wanted to avoid the added toxicity of nitro for me and for the environment. Perhaps that's an eye-roller for those of you more in the know about finishing, because I may be misinformed. If so, please set me straight.
I am definitely concerned about the learning curve in spraying. I also make ukes and those get TruOil which looks great on that instrument. I really wanted a more "professional" looking finish for the guitars. French polish is beautiful, but I don't enjoy doing it and it isn't very durable. But I have a lot of patience, and am willing to do a lot of test panels before I go live on a GSO.
Thanks again! Beth