HVLP Touch Up Guns

[Ferrino]

I've been looking at some touch-up/detail guns for painting smaller parts and notice that, not only is the cup smaller, but the tips are smaller than regular-sized guns too. I am seeing tips in the range of 0.8-1.0mm. To get these to work with the same paints that you are shooting with, say a 1.4mm tip on a regular gun, is it simply a case of adding more reducer to get it to flow?

Would it be possible to spray something like epoxy primer with a tip as small as 0.8mm? For example, when spraying smaller parts with lots of different angles, like an engine fan.

Thanks!

[Doug_B_928]

^^^^Really good question to which I'd also like to know the answer.

[962porsche]

if your spraying top coats (bases, clear's , single stage then you should not have to reduce the products any more then with a full size gun .
the same is pretty much the same for your sealers with the reduction rates mixing to the manufacturers spec's .. but i have found some of the filler primers that you can also use and mix as a sealer will need just a splash more reducer .
when it comes to primers most will take just a little more reducer to get it out of the gun and to lay down flat on the substrate .
the amount will very for different primers and the mil build they offer .
do a test spray out 1st just mixing the manufacturers spec's see how it sprays and lays out .
if need be add reducer as needed . most times just a little is needed and try picking a primer that can be reduced or offers a reduction option for it and use there recommended reducer some thing like U-pol's primer sealer .
if your spraying a high metallic flaked color it will change the shade of the color just a little at time if you have no way to tint the color your self your kind of screwed with this .
most of the time you will still not see a shade difference in the color but if you do you can adjust the air pressure some to adjust the shade the same . a lower pressure will tend to darken a high metallic color .

[Ferrino]

Thanks for the reply - I will give it a go! I was initially thinking of testing it with an epoxy primer. The brand I have says it can be reduced up to 20% with a urethane-grade reducer (which I have from the same company). An example part would be the tail light housings I recently blasted. I want to epoxy prime these and then shoot the bulb housings with a white paint.

[Doug_B_928]

How did you make out spraying epoxy with the touch up gun?

[Ferrino]

Originally Posted by Doug_B_928

How did you make out spraying epoxy with the touch up gun?

Life got in the way and I haven't had a chance to try it out yet! Part of the problem is that I've needed to upgrade my compressed air system to control moisture, so I've put together an aftercooler that sits between the compressor and the tank to cool the air: works incredibly well. I just completed the plumbing, so I should be able to blast and paint some parts soon...

[Doug_B_928]

I look forward to hearing how it goes. If it works for you I might try it with an LVLP touch up gun (.8mm).

Your aftercooler setup sounds interesting. If so inclined, you could document that on this forum. I'd certainly like to see it.

[Ferrino]

Originally Posted by Doug_B_928

I look forward to hearing how it goes. If it works for you I might try it with an LVLP touch up gun (.8mm).

Your aftercooler setup sounds interesting. If so inclined, you could document that on this forum. I'd certainly like to see it.

Sure, I will start a thread on the aftercooler once I've tested it a little more, including all the parts I used. I picked up a 0.8mm Harbor Freight detail gun for testing the epoxy - I read that someone had good success shooting SPI epoxy with a 0.8 by using 10-15% reducer. Now just need to find some time!