Dumb spraying questions....

[dbhost]

To start off with, some disclosure. My only spraying experience is from a rattle can, a Wagner Power Painter, or access to my BIL's body shop with their monster compressor that would take up most of my shop... I am wanting to do something a bit more reasonable...

I have some projects where spraying finishes, particularly to get the finish into corners and such, is an extremely appealing option, however I know little to nothing about spraying requirements and the guns themselves...

What I see with most guns I come across is that the CFM required is well beyond my 8 gallon compressor, and even beyond most 30 gallon compressors I see on the market. Now I will admit I am cheap sometimes, primarily out of necessity, however I am less concerned with the prospect of upgrading to a bigger compressor for cost, as I am for impact to space consumption in the shop. The 8 gallon wheels very nicely under the stand for the dust collector, and thus takes up little overall real estate in the shop, and I like that. I've seen others with tanks up to 30 gallon that dimensions wise will fit, but would be a pain to pull in and out for use...

I would assume however, that the CFM usage rating on the guns is constant spraying, which I would never get anywhere near doing. So with that in mind, I am thinking that CFM requirement might not be as critical as it initially appears

The finishes I am interested in spraying would run a very wide range from oils, to latex paints for painted projects, and even automotive type finishes for refinishing parts for the truck. (Specifically my Delta Toolbox that I need to finish a project on soon... I need a welder!)

Now that you know that. I will get to the question...

What would be the best gun, or guns for use, that are reasonably priced, and how do I thin the products in question prior to spraying? Likewise, how do I clean the guns afterwards?

I am considering compressor driven guns, as well as the turbine setups from HF, Rockler, and possibly the Graco unit from Lowes... I need versatility, good finish, and a small format...

[jking]

A few years ago i bought the HF HVLP sprayer. The one that has the turbine included, not a spray gun for a compressor. I have only used it for painting some shelves for the kitchen and seemed to work well. I thinned the paint with water (even though the can said not to thin), I also added some Floetrol. I don't remember how much, I followed the recommendations on the can. I sprayed water based paint, so, for cleanup I ran water through the gun several times & then took the needle out & washed everything with hot soap & water.

I have not used it on any other finishes. For the water based paint, it worked quite well.

[Lonnie in Orlando]

I'm a dufuss at spraying, but I've been pleased with my setup and results. I haven't sprayed clear finishes, but I have spayed enamel on wood and metal, 2K auto paint, and auto epoxy primer. Auto paint on small parts only - not an entire vehicle. I just finished two days of spraying parts for my '54 pickup.

I use a HF 21gal compressor and a HF HVLP gun. Both of which have been discontinued. I let the compressor catch up when painting large projects. Here is my equipment and the closest HF equipment available:

> COMPRESSOR:
HF #94667 compressoor - discontinued
21gal, 120v, 3HP, 14.3 A, 7 SCFM at 40 PSI, 4.9 SCFM at 90 PSI

closest available:
HF #67847
21gal, 120v, 2.5HP, 14A, 5.8 SCFM @ 40 PSI, 4.7 SCFM @ 90 PSI
http://www.harborfreight.com/25-hp-2...sor-67847.html

> HVLP SPRAY GUN
HF #90977 HVLP gun (discontinued) 5.9 CFM 29 PSI/ 50 PSI

closest available:
HF 66222 12 SCFM @ 45 PSI 15-45 PSI
http://www.harborfreight.com/high-vo...gun-66222.html

Also available - lower stated CFM requirements, but does not have a regulator on the gun. Quality unknown.
HF #47016 8 CFM @ 40 PSI 20-50 PSI Low price.
http://www.harborfreight.com/20-oz-h...gun-47016.html
Buy a regulator to attach to the gun - see REGULATOR below.

> DRYER / FILTER / REGULATOR
HF 1118 Filter and Regulator.

closest available:
HF 68247 filter and regulator
http://www.harborfreight.com/industr...tor-68247.html

> FILTER AT GUN
Motor Guard D-12
http://www.motorguard.com/air_3_3.html

> AIR BRUSH
HF #47791 Airbursh similar to one I have
http://www.harborfreight.com/airbrush-kit-47791.html
(Good for very small jobs and tight places. I've used the airbrush to paint wall switch plates with latex paint thinned with flotrol and water )

> REGULATOR
HF #68231 125 PSI Air Flow Regulator with Gauge
http://www.harborfreight.com/125-psi...uge-68231.html
Similar to one I have for air brush and for cheap no-gauge gun - HF number unknown.

I set the compressor to 90#. 25' of hose to the Dryer/Filter/Regulator. Set the dryer/fil/reg at 50#. 25' of hose to the gun. Set the regulator on the gun at 29#. Adjust the air to the nozzle with air adjusting knob on the gun.

I thin enamel about 50% with paint thinner. Thin auto paint as instructed on can. I clean gun with paint thinner w/enamel; with laquer thinner w/ auto paint.

Spray gun info:

Fine Woodworking Jul/Aug 2010 pp68-73
Wood Mag Apr/May 2008 p78-81
Pop WW Dec 2005 p98
Pop WW Feb 2006 pp98-99
American WW Jul 2003 pp28-38

http://www.purplesagetradingpost.com...Pspraygun.html
http://www.woodcentral.com/russ/finish11.shtml
http://www.spraygunworld.com/Informa...odworking3.htm

Good luck,

- Lonnie

[cabinetman]

There are a few steps you can take to get the most out of a small compressor in a small space. I suggest not to install a filter at the compressor. Rather, run piping (or airline) uphill, for a short run and then back down. Install a drain valve where the line diverts uphill, and when when the downpipe ends. Off to the side of the airline mount your filter, and regulator (see drawing below). Run your hose off of that regulator to the gun. On the gun, install a small regulator and disposable ball filter.

Filters right on the compressor are not efficient. Air pressure blows moisture by. Running the up-pipe to the remote filter allows moisture in the line to get trapped and gives the airflow a chance to cool.

For spray guns, many HVLP's require less CFM's than pressure feed. With a small compressor, that isn't all that important, as your spraying will have to accommodate the compressor. I would suggest a conventional style gun (not gravity feed). What will make for successful spraying with any gun is practice, and familiarity with the gun. Technique is what it takes. Learning the correct air/fluid mix, pressure to the gun, pattern shape, distance from the subject, speed of movement all play in getting good results.

You can practice with spraying water at cardboard. Use plenty of light, so you can see how wet your application gets.

.

[dbhost]

Thanks Lonnie...

The compressor I have, is the now discontinued 40400, which has the same specs as the #67501
4.5 SCFM @ 90 PSI, 5.5 SCFM @ 40 PSI

It looks to use the same motor / compressor components, just a different handle, flipped around motor / compressor, and 2 front legs instead of one. It's okay at best.

Cabinetman's drawing of the air line rig is what I had in mind... Problem is, funding to pipe it... :-(

I don't know if they still have the rapidair knockoff at HF, but that would be a good solution. But yeah, come out, go up and over, then drop down to the filter AFTER a regulator to pull the pressure down, then filter, and finally to the gun... (or nailer, or impact wrench or...)

I drain my compressor after every use, so water in the lines should be a non issue... However I am not allergic to when I hard plumb it in, putting ball valves at the lower corners of the lines to blow those out as well...

I will have to look into the guns. Yeah, a suction feed would be easier in the regard that you can set it down. But then again, a gun stand is no big deal...

[cabinetman]

Cabinetman's drawing of the air line rig is what I had in mind... Problem is, funding to pipe it... :-(

I don't know if they still have the rapidair knockoff at HF, but that would be a good solution. But yeah, come out, go up and over, then drop down to the filter AFTER a regulator to pull the pressure down, then filter, and finally to the gun... (or nailer, or impact wrench or...)

I drain my compressor after every use, so water in the lines should be a non issue... However I am not allergic to when I hard plumb it in, putting ball valves at the lower corners of the lines to blow those out as well...

I will have to look into the guns. Yeah, a suction feed would be easier in the regard that you can set it down. But then again, a gun stand is no big deal...

You could get away with diverting the airline with hose instead of hard piping. Instead of using ball valves, as they are pricey you can use brass drain taps, AKA "petcock".

.

[LCHIEN]

Have you ever looked at the Critter sprayer - its a low CFM, inexpensive sprayer that uses mason jars for feed allowing you to save your finishes in an inexpensive, readily available air-tight sealable container. Works well with a pancake compressor. Overspray may be a little higher than with a more expensive sprayer. But generally got great reviews for bang for the buck esp. with smaller compressors.

It has gotten great reviews and costs about $40 at Amazon.
http://www.amazon.com/Critter-Spray-...8028001&sr=8-2

if you do a search here at BT3central for "Critter sprayer" you'll get a lot of hits,
http://www.bt3central.com/search.php?searchid=1831474
, but i haven't heard it talked about in the last couple of years.

This is one of the later ones:
http://www.bt3central.com/showthread...ritter+sprayer

[cabinetman]

Have you ever looked at the Critter sprayer - its a low CFM, inexpensive sprayer that uses mason jars for feed allowing you to save your finishes in an inexpensive, readily available air-tight sealable container. Works well with a pancake compressor. Overspray may be a little higher than with a more expensive sprayer. But generally got great reviews for bang for the buck esp. with smaller compressors.

I don't know if you have one and have tried it, but I give it a thumbs down. I got one as a gift about a couple of years ago. It's more of a toy as far as I'm concerned. If a small spray gun is what's wanted, a detail type gun like this has accurate fluid/air mix control, and pattern adjustment. I've run this type of gun on a 1/2hp, 7 gal tank for on the job spraying.

.

[mpc]

I have the HF HVLP turbine & sprayer; I've used it for a few items and it's worked well each time. The last job was spraying regular house paint onto new furnace registers; I thinned the paint just a little bit and got excellent results - smooth, no brush marks, and good coverage into the various nooks & crannies of the vent slots. I read somewhere (probably this site) that the Rockler unit is the same as the HF unit in a different box. They certainly eyeball the same to me.

I also used it to spray some polyurethane eons ago and that went well too.

I find using it is sortof like using a food processor - it does its job quickly... but clean-up often takes longer.

As for using a regular paint sprayer on your existing compressor... a few things to consider:
1: tank size mostly determines how long you can use higher CFMs than your compressor is rated for; a large tank doesn't always go with higher CFMs. CFM capacity is set by the physical size of the compressor pistons/rotors.

2: most "home shop" air compressors come with regulators that absolutely stink at flowing high CFMs. In fact, many regulators can't flow enough air to meet the CFM rating of the compressor! Don't be surprised if you have to replace the stock 1/4 or 3/8 inch regulator with something designed for 1/2 inch piping. My Sears Craftsman compressor, many years old now, is rated at 6.3 CFM @ 90 psi but I could never power air tools like a grinder (continuous flow, not short burst flow like nail guns or impact wrenches) because the stock regulator couldn't satisfy the CFM needs of the tool. I ended up adding my own piping, including a ballcock valve ahead of the regulator, for such tools. Later I found (at Sears no less) a better regulator with a small glass moisture separator too. That one flows well.

3: To go with the high-flow regulator you'll probably want high-flow air hoses: that means something larger than the typical hose. I use half inch hoses now. Same for the quick-disconnects and other unions.

If you make similar mods to your existing compressor you might find the 8 gallon tank will let you spray for several minutes at a time before you have to take a break and let the motor+pistons catch back up. Note too that most compressor motors are not designed to run continuously - they have a "duty cycle" limit of typically 50%. So that means you want the compressor motor running no more than 50% of the time. Another option are the "secondary" tanks for compressors - basically another high pressure bottle that'll add gallons of space. Often these are sold as ways to use air tools remotely from the compressor - your compressor fills them, then you take the tank to the job and run the tools off the tank for a while. Many have "in" and "out" ports so you can stick them in series with your compressor making it act like one big tank; those with only one port will require a "T" fitting to tie into the existing tank piping.

mike c.

[JimD]

I used to use a Wagner Conversion gun - a HVLP that works off a compressor. I managed to finish some things with it including a bunch of plantation shutters. But it was a struggle. I don't know how much of my difficulty was my compressor (it's smaller than yours) and how much was the gun and how much was me. It seemed awfully hard to get it adjusted. But when it was adjusted well it was fine.

I now use a Fuji Mini-Mite 3. It is hugely better. No thinning of water based clear finishes. Patterns as small as you want up to a foot or more. Easy adjustments. It costs more than the guns you are looking at but I would have saved money by just buying it first. You can get needles (as you can for the Wagner) for thinner and thicker finishes.

Jim

[wardprobst]

I've got a bunch of stuff, like Jim D I have and like a Fuji, customer support is great. I see them on the forums used occasionally. If you go with a compressor, I'd get a good quality HVLP gravity feed, I've got CAT Jaguar which may be out of reach price wise but is a fabulous gun. In Houston, I'd go with the Fuji, it will dry the air a bit as it goes through the turbine. Be sure to protect your self and your projects from over spray.
Best,
DP

[jabe]

I like cman's diagram for the air compressor set up. Having the drain valves are important to keep moisture out of the lines.
Anyway, I've sprayed with air compressor, HVLP turbine systems and airless system, all work well when set up right. I have 3 types of spraying systems, air compressor (craftsman), Fujii HVLP turbine and Graco airless sprayer. For small projects & cabinets, I like using my Fujii HVLP system it uses less spraying material so it saves $$$ and it's quiet. It's small and easy to take to the job site and little over spray. Why I went with the Fujii spray system was when I had questions on their product, the owner of the company would reply, now that's customer service. Of course my GRACO airless sprayer is used only for spraying homes, it works really well. I hardly use my air compressor for spraying anymore, too noisy.

[wbsettle]

No personal experience, but this unit gets high marks in the DIY projection screen section at AVSforum, suggesting it'll lay down a very smooth finish. Supposedly it's the Graco HV2900 without the labels. Only $49.

-Brent

[pelligrini]

Not sure what the budget is like, but I saw that Peachtree has an Earlex on sale:
http://www.ptreeusa.com/edirect_101111.htm

[dbhost]

Not sure what the budget is like, but I saw that Peachtree has an Earlex on sale:
http://www.ptreeusa.com/edirect_101111.htm

That Earlex is a nice system for sure, but no, that price tag is more than double what I had in mind... My upper limit would be $150.00. I am not making a living with this, or even intend to. My intention is to make certain jobs easier is all...