What paint gun?

[Suzuki_Don]

PSYGUY,

I am watching this link closely. I need to paint my tank, ducktail and sidecovers. All the info from the guys on spray guns, compressors is very helpful. I will try out my technique on the sidecovers as they are a bit rough and have hand painted badges on them (not by me).

I am waiting to see if there is any tips to be given on paint selection, preparation between coats and adding hardener and other stuff to the paint. Also mixing of paint would be useful to know about as well.

Anyway just watching and waiting.

[Nessism]

Psyguy,

or this mini gun>>>>> http://www.spraygunworld.com/product...-%20AP4020.htm P/n 4020-1 (1.0mm tip) P/n 4020-12 (1.2 mm tip)

That's the one I'd get if you are on a budget.

[rustybronco]

with regards to guns, it seems that cheaper guns don't necesarily differ from the more expensive ones in specs, so i assume the difference would be mainly in the quality of the parts?

any further tips welcome

Psyguy,

They differ greatly in the design and in the machining of the parts.

most "good" knock-offs are just that, ripped off copies of proven designs. spray guns are just another example of you get what you pay for. that's not to say you can't find a good spraying, low buck knock-off, but you will have to wade through all the so-so imitations. it's not an easy thing to do.

put a knock off in the hands of a "good" painter (I didn't say professional) and they will get the most out of it. put a good gun in a amatuers hand and they might be scraping paint off the floor.

all-righty then, on to the main point, tips...

the first thing you need to find out is, what materials are available to you. then find out what tip size the paint supplier recommends to use with those materials. next, see what size compressor you can lay your hands on. then and only then, begin dissecting what gun will fit your requirements.

and, as it was stated before... practice-practice-practice.

http://autobody101.com/download.php

***edit***
the gun I use is an Astro EVO-4014. It doesn't hammer paint on, but it sprays nicely. I have heard they changed the tip design on the EVO series, so I don't know if the newer ones spray as well.

[Macguyver]

Guns, lots of guns.

How convenient, I just got back from a paint training course that touched on sprayguns quite a bit.

IMO, the Devilbiss Finishline is a much better gun than it should be for the money. It comes standard with either a 1.2 or a 1.4 tip depending on the package you buy. Either will do the job of spraying primer or topcoat.
This is the gun I would buy (if I had to buy my spray guns, that is.).
Most painters use it for a primer gun with the 1.4 tip, but it is a very easy gun to use/clean, and gives great results with a little practice.

STAY AWAY FROM THE DEVILBISS PLUS GUNS! They are terrible build quality, poor quality control, and have serious corrosion issues when using with waterborne paint.

BTW after June 18th this year, suppliers will not be able to purchase non-compliant solvent borne materials anymore. They will be able to sell off remaining stock until Dec. 18th 2010, so if you do paint a fair bit and have a favorite solvent borne product, check with your supplier to see if it is V.O.C. compliant.

If it is not, it may be worthwhile to stock up between June and the end of the year, at the very least, check stock of your favorite solvent borne product with your supplier, and maybe reserve some for yourself.

Otherwise, get ready for low-V.O.C. compliant solvent borne, and water borne paint, primers, and clearcoat. I sprayed a fair bit of the new PPG stuff in the last couple of days, and the new "one visit" clear is amazing! EC700 is the stock number for it. Two coats is all that it needs. One medium coat with a 25% overlap, then immediately recoat with a medium-heavy coat, 25% overlap, to make it look how you want it to look when cured. Done. Super easy, polishes beautifully, amazing results.

I also would stay away from knock-off guns since the fan of the spray is almost always non-symetrical, so when you are spraying it is easy to put runs (or flow-indicators) on the paint job because the material is not being applied evenly.

The SATA line of guns are all excellent guns, debatably the best in the market right now. Pricey, and high quality. Stainless internals so it is waterborne ready right out of the box. If I had too much money to spend, I would have a SATA, or a Tekna, which are the main competitor to SATA, but at only 2/3 to half the price of the SATA.

The only reason most pros use two different guns for spraying primer and paint is the tip size. I use a 1.4 tip for primer, and a 1.2 for basecoat/clearcoat with a different air cap. I could use the 1.4 for clear, but I would rather put on a little bit less than a little bit too much in one pass. Just means you need to slow down a bit when doing the pass.

Even if you do get runs in your clearcoat, just wet-sand them out with 800 or 1000 grit, polish, and you are done.

Make sure your compressor is up to snuff, and you are using high-flow couplers. 98% of paint match and application problems are caused by inadequate air equipment. If your compressor is not able to keep up to the gun, then go buy a few $20 portable "air pig" tanks used to fill up flat tires, and daisy chain them together after the compressor, and before you spray gun to buffer the drop in PSI caused by heavy drops in pressure. Should be enough volume, even with a smaller compressor, to get a consistent coat of paint. Just make sure you let the pressure in the tanks get all the way back up between coats.

Hope this helps,

[rustybronco]

I also would stay away from knock-off guns since the fan of the spray is almost always non-symetrical, so when you are spraying it is easy to put runs (or flow-indicators) on the paint job because the material is not being applied evenly.

Hope this helps,

Normally I would agree with you, but there are a few good knock-offs out there that spray well enough for your average back yard painter. http://www.thegsresources.com/_forum...87&postcount=1

[posplayr]

Originally Posted by rustybronco
Psyguy,

or this mini gun>>>>> http://www.spraygunworld.com/product...-%20AP4020.htm P/n 4020-1 (1.0mm tip) P/n 4020-12 (1.2 mm tip)

That's the one I'd get if you are on a budget.

I checked and it is about $100 delivered on sale now. I might grab one while they are on sale.

I'm no expert but for painting a motorcycle, I just don't see needing a gun with much more that 4 oz cup. To spray a set of layers or primer, color or clear 8-12 oz is a whole bunch of paint an probably worth 5 coats for tank, side covers ,fender ...etc. With a 4 oz cup I just check the cup occasionally to make sure I'm not running out and typically only refill once for 8 oz total.

If I want to put alot of paint down, I measure out the amounts in by mixing cup and then divide it into the cup to make sure I space the coats out and don't run out in the middle of my final wet coats.

So for a motorcyle, and not wanting to waste paint a 4 oz cup is a nice size and less work to clean up.

The touch up guns use alot less air and this will be a problem with the larger guns unless you have a good compressor with high volume like one with 3-5 hp. This is typically a 240 compressor and not the 120 variety.

[posplayr]

PSYGUY,

Done it is almost ashame to sand off that vintage "lettering"

[Nessism]

People need to keep in mind that tip size is related to the size of the gun. Touch-up guns are smaller and typically use a narrower fan pattern than a full size gun, so the tip size (which is rated in mm’s) will correspondingly be smaller. A lot of mini guns use a 1.0 tip, which I’ve found is plenty for all but the thickest clears and primers. The same size full size gun would typically use in the 1.4 tip range.

[posplayr]

People need to keep in mind that tip size is related to the size of the gun. Touch-up guns are smaller and typically use a narrower fan pattern than a full size gun, so the tip size (which is rated in mm’s) will correspondingly be smaller. A lot of mini guns use a 1.0 tip, which I’ve found is plenty for all but the thickest clears and primers. The same size full size gun would typically use in the 1.4 tip range.

Ed,Dale
So if I grab one of those Asto Miniguns as Dale suggests, should I go 1.0 or 1.2; I have no idea what the size is for the gun I have been using? I have 4 or the cheapies, so this new one has to be for clear and color.

Is the tip size in mm something I can measure by just looking at the hole size at the outside of the tip?
Jim

[rustybronco]

Jim,
http://www.sjdiscounttools.com/asthvlp6gfs.html <<<<< scratch that, it has a plastic cup.

the only mini I have is a knock-off "Zhipp" with a 0.8mm tip. it's much too small for normal use.
I'm going to have to defer to Ed's comments on tip sizes for a minigun. (but I would fathom a guess that His answer will be to get the 1.0mm tip)

[Nessism]

The answer depends on what kind of material you are going to spray; thick primers and clears need larger tip than base coats and sealers which are thin. This is why the pro's have more than one gun. I’ve gotten by with a 1.0 tip but I’m inclined to recommend a 1.2 since you can always regulate it down. With the 1.0 tip I reduce the mixture until it’s the proper viscosity for my gun. This may not be the best method but it works fine most of the time.

[spyug]

I just wanted to chime in here. It hasn't been mentioned but airpressure is something thats so important to having the gun work right. Also temperature and humidity can affect the quality of the air i.e too humid and air can have water droplettes in it which will spoil the paint.

One of the mistakes a lot of first time spray painters make is not setting the compressor output pressure correctly. They sometimes assume that if the guns working pressure is between say 15 and 40 psi then the compressor out put should be set to that. This is why its important to have a regulator at the gun. Dial up the outlet pressure and control it with the rgulator at the gun.

In a lot of small at home compressors the pressure from the tank can drop dramatically from the tank to gun and setting the compressor output too low is going to make it worse. All fittings need to be tight and teflon tape on threads is key to a good seal as many cheap rigs use cheap and poorly manufactured fittings which could leak further lowering pressure. If the paint starts to splatter or drips from the tip the airpressure is way off.

In humid climates a drier in line with the airsupply out of the tank is another must but paint problems can still occur with excess humidity so keeping an eye on it and not painting with humidity over 40% or so is often recommended.

Just a few more things to think about.

Good luck with it and show us what you can do.

Cheers,
Spyug

[rustybronco]

Note to all that are interested... sign-up, download and read "basics of basics" in the link I previously posted. " it's good reading material "

[posplayr]

It hasn't been mentioned but airpressure is something thats so important to having the gun work right.

Well I think it has been mentioned but I will 3rd that though as I assumed for quite some time that the low flow of my touchup gun made having a regulator at the gun unnessesary and I was able to work around it with moderate success, but it meant having to run back to the compressor all the time from my booth to control the pressure. A cheapy regulator at the end of the hose (right next to my gun) works wonders.

[posplayr]

Jim,
http://www.sjdiscounttools.com/asthvlp6gfs.html <<<<< scratch that, it has a plastic cup.

the only mini I have is a knock-off "Zhipp" with a 0.8mm tip. it's much too small for normal use.
I'm going to have to defer to Ed's comments on tip sizes for a minigun. (but I would fathom a guess that His answer will be to get the 1.0mm tip)

I would go for this one as you previously recommended and seems to be the near identical specs to my HF gun.

Astro Pneumatic - AP4020 - HVLP MINI GRAV-FEED GUN 1.0MM
24-48 hour delivery to most of the US.
Your Cost: ON SPECIAL!

• High Volume Low Pressure Detail/Touch-up gun
• Stainless steel needle & fluid tip
Specifications:
Nozzle tip size: 1.0 mm
Air Pressure (at inlet): 41-44 PSI
Air Pressure (at cap): 10 PSI
Air Inlet thread NPT: 1/4" (male)
Average air consumption: 4 CFM
Required compressor: 1 HP
Weight: 1 lb.
Aluminum cup capacity: 0.130 Liter

AP4020 - HVLP MINI GRAV-FEED GUN 1.0MM