What paint gun?

[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. :lol:

 

[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.

[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]

[FONT=Verdana, Arial, Helvetica, sans-serif][FONT=Verdana, Arial, Helvetica, sans-serif]Astro Pneumatic[/FONT] - AP4020 - HVLP MINI GRAV-FEED GUN 1.0MM
24-48 hour delivery to most of the US.
Your Cost: ON SPECIAL!
[/FONT]

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[FONT=Verdana, Arial, Helvetica, sans-serif][/FONT][FONT=Verdana, Arial, Helvetica, sans-serif]
[/FONT]
[FONT=Verdana, Arial, Helvetica, sans-serif]? High Volume Low Pressure Detail/Touch-up gun
? Stainless steel needle & fluid tip[/FONT]
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

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[/FONT]​

 

[posplayr]

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.

I have tended to reduce whatever I'm spraying to get to a proper viscosity as well. I'll measure my current tip and see if i cant just match that at it likely the 1.0mm as previously mentioned .

 

[rustybronco]

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

Jim, I've never used that gun. but I have seen the fit, finish and spray qualities of both the HVLPDX3 and EVO's . if you don't like it, I'll buy you out of it.

If you do like it... do you have a spare Tek current probe you'd sell me cheaply?

 

[posplayr]

Jim, I've never used that gun. but I have seen the fit, finish and spray qualities of both the HVLPDX3 and EVO's . if you don't like it, I'll buy you out of it.

If you do like it... do you have a spare Tek current probe you'd sell me cheaply?

I really like my HF gun that I have bought for $10. I have already moderated my expecation to NOT expect 10 times beter performance from a cheap $100 knock off.

I only have the current clamp/probe that goes with the Tek scope.

 

[Guest]

i already have the sealer and the primer on so need the gun for the color and clear.
i now understand (??) that i may need two different tip sizes as the two-pot clear is usually much thicker than color/base or i may be able to get away with just adjusting the viscosity and air pressure.

i already have the paint supplies from PPG so i'll check their data sheets to see what they recommend in terms of the gun tip sizes.

and need to find some good scrap bits to practice on. corrugated iron roofing sheets should do

 

[Suzuki_Don]

Don, it is almost a shame to sand off that vintage "lettering"

Yes Jim, I know it will devalue the bike. But I was thinking that the PO did not like the side covers and that is why he left the bike lying under a tree.

 

[Nessism]

i already have the sealer and the primer on so need the gun for the color and clear.
i now understand (??) that i may need two different tip sizes as the two-pot clear is usually much thicker than color/base or i may be able to get away with just adjusting the viscosity and air pressure.

i already have the paint supplies from PPG so i'll check their data sheets to see what they recommend in terms of the gun tip sizes.

and need to find some good scrap bits to practice on. corrugated iron roofing sheets should do

The factory paint data sheets typically assume a full size gun, compared to the typical touch up sized gun for painting a motorcycle, so you need to reduce the tip size accordingly per discussion in this thread. 1.0 or 1.2 is fine for both base coat and clear if you are using a touch up gun.

 

[ukilme]

This is a good read.

Laws in your country, state or province will dictate which paint you can use. Like mentioned in a previous post, Ontario Canada requires water borne pain as Jan 1-which on a side note gets merimer and clear does not have to be.

If you want a good water borne paint check out autoaircolors.com. But I see that you got PPG already.

For a good web site to read check out http://www.kustomkulturelounge.com/forum/

The site is maintain by Craig Fraser and he is well known in the paint business and airbrush business.

There is also airbrush.com that is a good website to search and learn.

And finally check out hotrodders.com. These guys have a crap load of info on body work.

Now with the guns that I use, I just have a small compressor 5 gallon tank with 5.2 at 40psi and 4 at 90 psi. It is not large but works for small thing like helmets and bike parts. I would not use it for a car or such. When I choose my guns, I kept these rating in mind.

A regulator at the gun is a great idea but I get around this by having a test panel on a wall and checking the spray before spraying.

 

[rustybronco]

And finally check out hotrodders.com. These guys have a crap load of info on body work.

Is Hotrodders still nothing more than a giant mouth piece for SPI products?

 

[Nessism]

One thing I’ve learned by lurking on a paint refinishing forum is that the gun inlet pressure is significantly different that the spray pressure at the cup (what ever that means). For example, if the paint instructions say to use 15 psi “at the cup” for an HVLP gun, you need about 40 psi at the gun inlet. This detail made a pretty noticeable difference with my SATA mini-jet, particularly when spraying thicker paints.

 

[posplayr]

One thing I?ve learned by lurking on a paint refinishing forum is that the gun inlet pressure is significantly different that the spray pressure at the cup (what ever that means). For example, if the paint instructions say to use 15 psi ?at the cup? for an HVLP gun, you need about 40 psi at the gun inlet. This detail made a pretty noticeable difference with my SATA mini-jet, particularly when spraying thicker paints.

How to measure pressure at the Cup?