I will be painting my '64 coupe soon. I will be using PPG Acrylic Urethane DCC and spraying Ermine White. I have a Sata 3000rp gun with a 1.2mm tip. The tech sheet from PPG says to use a 1.3mm tip. What would be the down side of using the 1.2mm tip with this non-metalic paint or should I buy the bigger tip? Your advice is always appreciated.

 

Dave,
For what it is worth. To a point. The tip (needle size) of a gun really does not matter. Not you do not want to use a 2.0mm tip when one is "supposed" to be 1.3mm...but even if you had one. You can cut back on the fluid to the point that when testing the paint on a test panel you could find that even with a 2.0mm tip...it would work. NOW...it may cause for travel speed and distance from the panel to change...but none the less...it would work.

With your very slightly smaller tip...you may find that you would slightly open up the fluid setting to compensate for this minor difference.

The main thing here is to TEST BEFORE YOU SPRAY THE CAR. Once you find that with the correct choice in reducer and thinning ratio...and gun adjustment...it should work out fine.

You have to understand that many of these "recommendations" are just that...recommendations from the paint manufacturer(s). They can be adjusted/altered a bit to make the product work for a particular situation...and does not mean that if you alter something that the product will not work. BUT...it may require added flash time and added coats of the product IF the changing of these prescribed mixtures and "what-have-you" are too far from the "standard".

It is all in the testing and choice of reducer for your situation. And just because "they" say to use a particular reducer for the current temperature that you are spraying at...it may require a grade slower instead. Sometimes using a slower than recommended reducer allows you to have better control of the paint and not have to "fight" it to get it on without a lot of orange peel.

Viscosity of the paint, distance from the panel, air pressure being shot at, and volume control on the gun (along with fan pattern) and overlap all make a difference. YOU MUST act like a robot when painting and keep things consistent.

Just my opinion...naturally.

"DUB"