Printable View
Can powder paint go bad due to age? Have some of the same color,type, brand that are not what they used to be-paint sticks excessively to heated head,dulls in color( transparent colors),and generally have gotten to be a pain in the caboose. My man-cave is air-conditioned,so heat is not the culprit. These powder paints seem to have just gotten old and are dying! Hope my question makes sense.
I have some powder paint that I bought 12 years ago and it's fine. I keep it in the containers it came in. I also have a cup for each color so even some of them have had paint in them for years and no problems!
Skip
I suppose that could happen. Not sure when the paint was purchased but it could be like a lot of other things. Companies really have no way of knowing how long something like that would last because they simple have not existed that long to have tested it.
I am like Skip, I have tons of paint and have not had an issue however Mine usually doesn't last that long when you are painting 3/4 or 1oz jigs in bulk.
I have two particular colors that, for whatever reason, just never work correctly. I have to spend either a ton of time stirring it, or really fine tune my fluid beds for those two colors. They seem to be more powdery than others. I've ordered several cans of it with the same results. I've gotten used to it and have learned to work with it, but I dread a large order of either of those colors!! The rest of mine are good. Never had one "change" color over time. I've had some that change slightly from order to order depending on the amount of pigment the company uses but never one that changes in the jar over time.
Let us know if you find out anything.
Humidity. I have some powders that got exposed to some high humidity and they started doing the same thing you describe. I popped the covers off and set the jars in a dehumidified room for three days, ran the powder thru a really fine sieve and put it back in the original jars and they work fine now.
Some colors are about the texture of dust in the jars while other seem a wee bit coarser. I think it depends on the character of the colors themselves and how well they granulate during manufacture. I don't air bed powder paints but I do keep them stirred real well while using them.
The colors your having trouble with add some clear in and that will thin it without changing the color!Quote:
Originally Posted by wicklundrh
Skip
Never had any powder go bad. Think ctom is on it with the humidity from AC
The AC should remove humidity not add to it! The AC actually removes humidity as it cools. My powder is always in the house so in AC or Heat depending on time of year, but never a problem!
Skip
Not sure if this will make a difference but I remember reading something on some of my fluid bed containers that said to place them in a paper bag when not using them. I don't store my powder in my fluid bed cups that much so I never used the idea. Might be something to it.
I'll try some clear with the two colors in question. CTom is right though, if memory serves me, those two colors are like powdered sugar compared to others that are more granular. I know that I have to turn the fluid bed way down on those colors.
A/C will remove humidity from the air that passes thru it but a home can have areas where the a/c is not doing much for the air present. Most homes will have the cool air going to where people frequent the most. Furnace and laundry or utility rooms can be hotbeds for damp even in air conditioned homes unless a dehumidifier is used. Here in Minnesota coding has houses sealed up so tight that other codes require a constant source of moving air inside the house. This "other" air is brought in from outside initially. During the summer months when humidity is high, the transition to being inside where the air is colder can create a ton of moisture so even homes with great A/C can have moisture issues. If anyone wants to see how ell moisture can get into something, take a powder paint jar that's empty and fill it with salt and set it on a work bench for five months, then open it. Moisture will have made the salt grains stick together and make a crust. Moisture in a home is nothing but the devil at work and it can get into every aspect of our lives even when the A/C is running on high.
The enemy of stored powder paint is heat. Pro-Tec recommends storage below 80 degrees F. I store mine inside the house. It only goes out to the (un-air conditioned) workshop when I'm painting.
Tom
Sounds like your paint is fine and it might be technique. Could be you are overheating your jigs (before you apply paint) or you might have increased your cure temp/time. New oven or heat source?
Usually high humidity will cause your paint to clump.
wicklundh - there are several mediums that can be used for filter material. For the problematic paint you should use a membrane with a larger pore size, maybe 3 micron...