Powder coating ovens....

Hey guys,

A while back I took delivery of some gas fired industrial cooking ovens specifically for the purpose of using them during my powder coating endevours. After I took delivery, I read somewhere (I don't remember where...) that gas is not acceptable. I'm puzzled as to why. These ovens were designed to be fairly even temperatured throughout, and the flame is not in direct contact with any fumes the process may cause. In fact, the only thing I can find that may not be suitable is the fan that circulates the air around does so at a pretty good clip, so I'll need to slow it down so the coating doesn't blow off while curing.

Can somebody tell me if there is any specific reason why I shouldn't use the gas ovens for powdercoating? I can't find anything on the topic....

TIA

 

Bill: Don't know why--maybe the powder will "gas off" and the oven will go BOOM! Really don't think so though. Many many years ago, during the winter in LA I used to heat "Crinkle" paint in the family oven (Mom complained about the smell) but no harm came from it. As long as it's outside and not in the house, I'd say give it a try.

Good Luck.

 

I've baked many items in my gas oven. Works fine for both drying and paint baking.

Maybe the flue gases will combine with the powder coat? Gas makes water vapor when it burns - maybe the humidity is too high?

 

X2

 

Burn gases/exhaust are not available to the interior of the oven that I can see.

Not like I've got much invested in this set up, it was given to me after all! I'll try something as a test that I'm not worried about and see what happens.....

 

They say never use gas fired ovens,unless used in conjuntion with a heat exchanger to keep the residues out of the curing chamber. Plus temp will vary more

 

You mean residues from the gas flame, right? If so, then I'm not concerned about that, there's no way for the residues from the flame to get into the chamber. And this is an industrial oven, so I would believe that the temps would be more uniform than a convential home oven.

Just gotta get the overly active blower problem fixed...

 

Hydrocarbons make CO2 and water when they burn. Is that what you mean by residue? Natural and bottle gas burn very cleanly, so there's very little else remaining.

 

I've worked with all types of laboratory and industrial ovens and no matter how cleanly it burns and isolated the gas is, it will still affect the product in the oven.

I can see fan speed also being a factor.

Just a side note, several tobacco companies are eliminating fast-cured tobacco (cured with propane heat) due to the fact that the gas residue adds/creates thousands of different compounds to the product. They use old mining caves (controlled environment) and heat lamps in Canada.

I don't know much about powder coating, but is there an electric oven available for the size work you need?

We have a local powder coater who has alot of trouble with his process (mainly in the summer). I used to do body work for an excellent painter around the corner. The problem is that they are in farm country and the painter learned very quickly that he had to work around the crop-duster's schedule. It ruined 2 or 3 auto finishes before he caught on.

gj

 

Thanks GonzoJohn! I'm afraid that the cost of the gas ovens was something I couldn't debate. Free is such a nice word after all! I did have
to plead and beg a bit for them, so I wouldn't feel comfy going back and asking for an electric version. Oh well, I'm not doing parts for NASA or anything, so I'll give it a try and work with what I have.

Thanks for the reply though!

 

YVW. I would think that the majority of exposure would be during placement & removal of the product in the oven. A large exhaust fan in your work area may help.
I learned many moons ago that I get what I pay for & sometimes pay for what I get... NYUKK NYUKK.

gj

 

Just another bit of information to throw into the mix: I was talking with a friend who owns the local auto parts and service center yesterday, and he told me about some trouble he is having with the city getting the ovens certified in his new powder coating business. Seems they don't want him to hook up the GAS lines until he has the OK from the fire marshall. Apparently, it is possible to process powder coating using gas, though maybe they are specialized ovens. BTW - he was telling me about a new powder coating process he'll be using that lays down a candy-apple finish. Almost transparent, glass-smooth and tough as well.