Priming in cold weather

[AndyWAUS]

I did not find any temperature restrictions in the SW P60G2 manual, so wanted to ask the collective mind. Should I be concerned about applying the primer when it’s cold outside, say 32F? Is it better to wait for a warmer day? Should I add extra reducer? Thanks in advance for any tips.

[lr172]

Originally Posted by AndyWAUS

I did not find any temperature restrictions in the SW P60G2 manual, so wanted to ask the collective mind. Should I be concerned about applying the primer when it’s cold outside, say 32F? Is it better to wait for a warmer day? Should I add extra reducer? Thanks in advance for any tips.

Don't know anything about that paint. However, Most 2K PU paints and primers cannot be spayed if either the paint or the sprayed surface are below 60-65* F Check the data sheet. Some epoxy primers must also be held at 60* for a period of time to avoid it from going dormant.

Larry

[burrm]

In my experience it's not necessarily the ambient temperature that's the problem, but rather the temperature of the primer/reducer itself and the parts. It tends to get a bit thick and "stringy" when cold and doesn't seem to adhere as well to cold parts.

What I usually do is mix the primer/reducer inside at room temperature and warm the parts up to normal room temperature (if they aren't already), then take it all outside at the last possible minute right before shooting and then bring them back inside after to dry.

[Jetmart]

Originally Posted by burrm

In my experience it's not necessarily the ambient temperature that's the problem, but rather the temperature of the primer/reducer itself and the parts. It tends to get a bit thick and "stringy" when cold and doesn't seem to adhere as well to cold parts.

What I usually do is mix the primer/reducer inside at room temperature and warm the parts up to normal room temperature (if they aren't already), then take it all outside at the last possible minute right before shooting and then bring them back inside after to dry.

I found that the temperature o the compressed air was really important as well as the parts themselves. I have a large compressor which held enough air for the entire batch of what I was priming. I put the parts in the spray booth along with the compressor and used a space heater to heat overnight. Then removed heater for spraying. Had the paint in the house along with the reducer overnight. I sprayed this way well into the teens. I had the paint booth, the parts, the primer, and the compressed air well above 70. I found the air was very important to be warm.

[AndyWAUS]

Thank you all for your advice. Reporting back my results.

I preheated the parts, tools, primer/reducer to room temperature. I also put a heater directly in front of the air intake of the compressor. My compressor has a small tank, so it had to run while I was working.

It sprayed fine. The result is not great, but I think is acceptable. The main problem is there is a pattern of little tiny dots of paint as opposed to uniform layer. The result is more pronounced the further away I held the spray gun from the parts. If the gun is really close to a part, the paint applies uniformly, as it is liquid enough to smooth out the pattern. When the gun is held further away, as I had to do with really light parts such as elevator rib halves, there is this pattern of dots. I assume the atomized paint hardens too much while flying through cold air before it hits the parts.
It doesn’t bother me too much, and I still get the parts fully covered with paint. It just looks kind of like a corroded piece of aluminum, so I wonder if it will be harder to detect actual corrosion if any develops.

[wirejock]

Originally Posted by burrm

In my experience it's not necessarily the ambient temperature that's the problem, but rather the temperature of the primer/reducer itself and the parts. It tends to get a bit thick and "stringy" when cold and doesn't seem to adhere as well to cold parts.

What I usually do is mix the primer/reducer inside at room temperature and warm the parts up to normal room temperature (if they aren't already), then take it all outside at the last possible minute right before shooting and then bring them back inside after to dry.

What he ^ said. I sprayed at least 1/2 my interior parts in the dead of Winter that way.
When it was way below freezing, I set up a temporary shower curtain booth in the garage.
Lots of pics on my blog.
P60G2 was always mixed 1 part paint to 2 parts catalyst.
Paints were usually reduced more than manufacturer recomendation because I prefer thinner paint.

[lr172]

Originally Posted by AndyWAUS

The main problem is there is a pattern of little tiny dots of paint as opposed to uniform layer. The result is more pronounced the further away I held the spray gun from the parts. If the gun is really close to a part, the paint applies uniformly, as it is liquid enough to smooth out the pattern.

This is normal, even in warm weather. Each gun is different, but most need to be 6"away to avoid dry spray (what you described). As long as the paint and part are warm, air temp shouldn't be a big factor. Be advised that reducers are temp based. THere shouild be around 4 different versions/drying speeds (fast, slow, very slow, medium), depending upon the temp of the paint and parts. In colder weather, you need faster reducers.

Larry

[AndyWAUS]

I have a further update for those who are interested. I called Sherwin Williams support phone and left a voice mail. They called me back today and provided this recommendation: "we would typically want to see a temperature of no less than say 58 to 60 degrees ambient in order for the product to set up and dry properly especially with it being such a thin filmed product".

Like I said, I've already applied it and it looked fine. Another thing I noticed after the primer fully dried - the tint looks lighter in color, almost grayish instead of the usual green. It was green before it dried.

[Anon455]

What is P60G2 used for?

I read the product sheet and saw these:

• P60G2 is not intended for use over adequate chemical treatments on steel, galvanized steel, or aluminum. Using P60G2 over these chemical treatments may result in loss of adhesion.

• Does not provide significant corrosion protection.

[wirejock]

Originally Posted by DARV8

What is P60G2 used for?

I read the product sheet and saw these:

• P60G2 is not intended for use over adequate chemical treatments on steel, galvanized steel, or aluminum. Using P60G2 over these chemical treatments may result in loss of adhesion.

• Does not provide significant corrosion protection.

P60G2 is the wash primer Vans has been spraying on QBs for a very long time.
Ask SW and they will tell you it's not intended as a stand alone primer.
Search and you may find Vans test piece has been outside exposed for close to 15 years with no sign of corrosion.
I sprayed it inside and also sprayed it under Jet Flex. Gorilla Tape test has yet to rip any off. In fact, the one time I needed to remove it, it took scotchbrite and lacquer thinner and a lot of elbow grease.
Personally, I believe it's all about surface prep. Feel free to read my blog.