Rickresource Rickenbacker Forum

I'm working on getting back into re-finishing. I was previously restoring P-basses using rattlecans because of availability of colors, easy setup, etc. I recently obtained an small Bostitch compressor and Campbell/Hausfeld 1qt gun, not really with the intention of spraying paint but to do some home improvement projects. I figured since I had both pieces I'd spray some of the furniture I have for the home improvement projects. I've had decent results but I'm sucking the life out the compressor. So my questions are:
Is this compressor ok for a small time re-finisher? It's a Bostich 2060p.
If so what's the best way to set it up?
Do I need additional valves?
Different gun?
Different compressor?
Thanks.

Hi Mike, and WELCOME TO MY 4700th POST!

The difference between "decent results" and "results I'm truly proud of", comes down to three things:

1. Professional materials
2. Good technique
3. Professional-quality equipment

The first is the easiest. Shop at professional stores. Stew-Mac and ReRanch (to name two) have decent lines of nitro both in spray cans and spray gun packaging, pints and quarts. But be aware that nitro--though highly-promoted by Fender and Gretsch as the more "authentic" finish, better for sound, etc", is really the victim of hype. It is not the state-of-the-art and is not the most durable thing around. As I've said before, I use PPG automotive urethanes (DBC) for everything except necks. I do spray nitro upon request, but only to keep things "historically accurate" on older Fenders and Gretsches.

Good technique is a matter of practice, practice, practice. But it's also paying attention. Just as, when you practice your playing and just drift around undisciplined, you'll learn slowly or not at all, so it is with spraying. Work out what you're doing right and what you're doing wrong, and stick with the positive habits.

Equipment--which is what this response is about, theoretically, at least--makes a major difference. Just as George was more sure of himself when he pitched his Futurama and bought his Duo-Jet, so will you be when you get a decent gun-compressor setup.

The Bostitch compressor is made for nail-guns. It is good for providing short bursts of high-pressure air to smaller nailguns and will do it all day long. One of its greatest advantages is its portability. But it serves very poorly for a spray gun of the size you're using. In compressors, you should look for a unit that puts out at LEAST 8 CFM (cubic feet per minute). Larger is better, you'll spend at least $400.00, and you can find them on eBay and in local ads cheaper, but they go quickly so don't hesitate.

Don't buy a so-called "pancake" compressor or anything that has one or two small tanks on the back--these are nailgun units:

Instead, buy a belt-drive, tank-type compressor, and try for a 10-15 gallon capacity.

There's another rule for compressors: except for nailgun units, many of which are built to be quiet, the smaller the belt-drive compressor, the louder it is. Quieter compressors cost a lot of bucks! Your $400.00 compressor will be loud enough to spoil your concentration if you let it.

Another fact: manufacturers (especially Campbell-Hausfeld) cheat unabashedly on their HP ratings. Forget the HP ratings--they are sales tools and as such are largely meaningless. Look at the CFM!

The second illustration shown above is a vertical-tank direct-drive unit. It's noisy and anemic, though impressive to look at for the uninitiated. Stick with belt-drive!

Spray guns:

Many different types are available. If your C-H gun has a threaded screw-on cup which hangs from the bottom of the gun below the pistol grip, hang it up and start over it's an internal-mix gun and could even be a pressure feed. If your gun hisses all the time when it's plugged in, it's a so-called "bleeder" gun, without an air valve, and it's why your compressor loses its breath. Any compressor would, with one of these:

You need a gravity-feed HVLP gun to spray today's paints, although a siphon-feed is OK, too (Gravity-feed ones are less tiring to use and more efficient.) You can get a Taiwanese-made one at any number of online stores or eBay for $100.00 or less.

Here's what one looks like:

Interesting stuff, Paul. The uninitiated (like me) would more than likely have stayed away from a nail gun compressor for the reason you state, but wouldn't necessarily have thought of the gravity feed gun. Come to think of it, the Badger gun that I use for model spraying uses a gravity feed bowl rather than a jar underneath, like the cheaper models.

The nail gun compressor was purchased to do just that, run 4000 feet of molding. I found out real quick that it just can't handle the volume and speed that I want to spray. The manual says that if the compressor is running more than 30 minutes in a hour then the application is wrong. Given that I kinda knew I needed to do something. Paul can you recommend any specific brand/model for a compressor? I've looked at Sears, Harbor Frieght and Grizzly as well as Evil-bay. Most the stuff around 20 gal is at best 6CFM. I'll probably want to spend around 400-600 bucks but it must be 110v. No room at my house to pull in anymore 220v circuits.
As for a gun the CH is the DE6500. Siphon Feed. It's good for now because I'm spraying some big items. I know I'll be adding a few more guns in the future.

Grizzly shows an H4519 3HP that puts out about 10 psi, which is about the smallest I'd recommend for serious finishing work. It goes for $240.00 plus shipping. It's a good unit, especially considering that Home Depot stocks nothing even remotely to its spec for even $100.00 more.

Harbor Freight has a couple of vertical units at reasonable prices. Their 55222-0VGA puts out 14.5 CFM and sells for only $330.00. Definitely a good buy.

Remember, you need a minimum of 8 CFM, and 10 is better still.

Now all you need is a good gun and you're ready to start.

Aitch, your Badger is fine for models, but won't spray enough volume of paint to do a good guitar finish, and won't even atomize the heavy clearcoat that I recommend.

Paul,you have mail.

Exactly right, Paul. It's fine for model ships and such like, but I'd never consider doing a refinish with it. I'd leave that to those who know what they are doing and have the right equipment.

Paul,

I've looked at the models you've recommended and basically I'd have to upgrade the electrical service to my house to deal with either one of those. So in a nutshell, no 220v for me. What are my trade-offs for less CFM, say around 6.8 with a 25 gallon tank? When you say serious refinisher, what does that mean? I'm using spray cans and a gun with a pancake compressor at this point so anything is going to be an upgrade. My goal is to refinish instruments and furniture for myself at this point with no timeframe to complete a project in mind. So I guess you can call me a semi-serious refinisher! Your thoughts on this model? Here is what I'm looking at - http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00919541000&tab=spe#tab

Thanks - Mike

Huh?

220V compressors draw half the amperage of a 110V compressor with identical motors. In the case of a compressor like the upright I showed above, startup amperage draw (when the motor works hardest) is nominally 15A@110V, realistically 11-12 most of the time. At 220V it'll draw 5.5-7.0A. That's peanuts for any house circuit. You may have to run an outlet for the compressor (your house will have three wires coming into the panel or (God forbid) fusebox. Two are HOT and one is RETURN. There will also be a ground wire. If you tap two of the hots, you'll get 220V single phase. If you tap one hot and the return, you'll get 110V single phase.

Any competent electrician can give you a 220V outlet for your compressor for low bucks.

Or, if you have a spare 20A circuit in the panel and don't want to run another outlet, most 220V motors are in fact dual voltage, with a diagram inside the terminal box to rewire them to "low voltage" in about 5 minutes, but you'll also have to change the line cord to a 110V, 20A type, which takes about ten minutes.

The Sears unit you've linked is typical of the "compressor wars" stuff that everybody produces. Note that the first figure they quote is "150PSI". Nice high number, Means NOTHING or possibly less. Spraying requires 35PSI at the most. Inflating a car tire requires 40. Now, truck tires--there you'll use 150 PSI. But how many truck tire repairmen buy their compressors from Sears?

The next figure is 6 HP. It used to be that a 6HP motor (odd number, that) was built on a substantial NEMA frame. Nema is the organization that was set up years ago to standardize the jillions of types of motors and make some sense out of claims made by manufacturers. I have owned 5 horsepower motors--TRUE 5 HP motors--that took two men to lift.

Sow how can a 6 HP motor be so small that you can't even see it in the photo? Answer: it can't, unless you find a way (for marketing and advertising purposes) to pull 6 HP out of a much smaller, 1 or 2 HP motor. They do it by quoting HP at stall, when torque is zero. Motors never operate this way, but the numbers look nice in an ad campaign. To keep these tiny motors putting out, they wind them to run hot:

One thing I always look for is motor speed, NEVER quoted by retailers. If the motor is running at 3450 RPM, l look elsewhere for my compressor. Sadly, these days, 90% of them run at 3450 RPM. This makes a simple and inexpensive piston-type compressor such as the one you're contemplating, sound like a JACKHAMMER. It'll drive you nutz.

What to do? Look for a nice used one that runs at 1725 RPM, and puts out 8 or more PSI.

Don't use an internal-mix "bleeder" gun.

Try to isolate your compressor from your spraying area (a good idea anyway, since very few cheaper compressors have explosion-proof motors--a BIG black mark to the manufacturers!

So, buy the Sears unit if you must, but put it outdoors when you're spraying, or in another room, or something. And spend a couple hun' on a decent gun...

Or you can learn how to French Polish...

Thanks for electrical explanation. I looks like I need to spend the time to find a competent electrician before moving on. My panel is full and I thought adding a 220 circuit would draw MORE current that what is there today. If it draws less then I'm sure I can move into the 220v and get a better compressor not to mention upgrading my table saw to 220v as well.