Painting Question(s)

Has anyone kept a record or know of an ideal humidity level for the painting area? By keeping the humidity level at a certain point do you have to add retarder because of the reduced humidity/faster drying? If so what percent retarder? ( Brodak Paint )

Heat, not the lack of humidity, would be the reason for adding retarder. But be careful with it. If you add too much you will experience meltdown where the top layers will eat into the bottom layers. If your shop is air conditioned, you won't have the heat to worry about and may not have a humidity problem, either. Then leave the retarder in the can.

The shop is air conditioned and I added humidity reducing equipment. The guage showed 80 % humidity before turning it on at 73 degrees. I left things running and on my return it was still 73 degrees and 60 % humidity. There was no blushing at this point but the paint seemed to dry a lot faster with not as much leveling.

Brodak'a dope dries extremely fast anyway. One of its good points. Did you thin it sufficiently? You need to thin it about 50-50 even if brushing, more if spraying. Thick stuff. You are buying dope, not thinner.

A temperature of "around" 70 degrees and a humidity of "around" 50% or less should be adequate to paint in dope with no retarder. As I say, don't go overboard if you use it. It may look nice at first, but do strange things later on if the under layers don't cure (dry) sufficiently fast enough.

Until I added an airconditioner to my shop, I used up to 25% retarder. Don't do this. Later on the paint under all the surface paint will craze and the final paint looks like it has some type of skin problem (in fact it does :_0)
I now never use more than 10% retarder, but Brodak dope must be thinned over 50% from the can/jar in order to spray paint. Retarder helps slow down the drying time in wet air or hot dry air and lets the dope flow out to a smooth surface (asuming the base is smooth too). Do NOT use any other thinner with Brodak dope. I don't care what anyone else says, this is asking for trouble. OK for cleaning the gun or brushes, but not for painting and don't even ask how I know this.

Retarder does just that, retards the drying time. It prevents (or at least lessens substantially) blushing because it gives the solvents (and any water present) an opportunity to gas off before the paint flashes. Blushing occurs in hot and humid conditions. Not so much if it's just hot, but the humidity is low. We used to paint outside (clearcoats) in Idaho in the summer. Well over 100 degrees, but humidity so low it sucked the water right out of your body. Never had any trouble at all with blushing. Ever. We did have to use retarder a bit so the paint was allowed to dry long enough for it to level a bit. Without at least a little retarder, the stuff would dry between the gun and the plane.