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In need of advice on cleaning

I have just started a small powdercoating business, a 30x30 shop with an 8' x 5' x 6' single phase walk in oven and a 6' x 12' x 7' powder booth also single stage,and a new pro series powder gun. I also have a 200 lb pressure blaster and a 2 stage 80 gal. air compressor [adv: air compressors on eBay or Amazon [affil links] . Now my question is this ... I do all the prepping work on parts such as media blasting and then spraying very vigorously with acetone ⇦this on eBay or Amazon [affil links] Warning! highly Flammable! until run off is clear.I then place in oven at a temp as if I was curing the part already for 20-30 min.then remove and spray again with acetone ⇦this on eBay or Amazon [affil links] Warning! highly Flammable! .I may do this process 2 to 4 times until no debris is noticed. I then powder coat and after the cure has taken place, I pull out after cool down cycle and dag gone it, I have gassing out bubbles present ... What am I doing wrong? Please help...this is getting very costly on my part ... Thanks,

Rocky Lane Honeycutt
POWDERCOATING & BLASTING - Woodleaf, North Carolina
2005

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Dear Sir,

Do not worry about the out gassing as it will not cause you much trouble for much longer - WHO suggested Acetone as a cleaner? Acetone is one of the most dangerous solvents you could hap-hazardously spray around your spray shop. Acetone has a very low flash point (highly, Highly flammable) so if you and your business wish to be around for the New Year STOP RIGHT NOW! :<(
Now here is the right way if you are still sound in body and mind - contact a US company who will supply the right cleaner. After cleaning, heat the article to 80 °C (to remove entrapped air)- before the article goes cold apply powder & then bake at the recommended time/temperature 12-15mins @ 180-200 C. Let me know if this improves things.

May I wish you an early Merry Xmas and A Happy New Year just in case :>)

Terry Hickling
Birmingham, United Kingdom
2005

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2005

I agree that acetone is very dangerous. And solvents are expensive, not to mention the fact that the state will eventually come to see you because of the volume of solvent you use.

To clean the parts, first decide which works best for you economically:

1. Media blasting is a very good prep for powder. It is labor intensive and expensive.

2. Install a dip tank that you can heat with gas or electric heat and contact a chemical supplier to obtain the proper chemicals for cleaning. Some suppliers have a dip or spray process which combines cleaning and phosphate coating, which improves coating adhesion. You can find a supplier by looking in an industrial directory. Most of the major suppliers can be found by doing a web search for Powder coating pretreatment. You probably have to rinse and dry the parts after the cleaner. You can dry in your oven. Follow the advise of your supplier. Also check local and state laws regarding disposal of spent solutions and rinse water.

3. Purchase a manual spray washer system. Many of these can re-cycle the pretreat chemicals and save significantly disposal costs.

Please, please, please stop cleaning with solvent!

Rocky, with regard to the out-gassing, what type of metal are you trying to coat, and what powder chemistry (epoxy, Hybrid etc.) are you using?

Daryl Spindler, CEF
decorative nickel-chrome plating - Greenbrier, Tennessee