Powder coating is a great finish if, the parts are pretreated (iron phosphate), the metal is perfectly clean, the cure time in the oven is met, and the powder is an exterior powder when used outside.
Doing it at home in your wife�s oven will get you in the doghouse for sure. Just the slightest amount of powder in her oven and it is there forever. Pretreat: in order for powder to stay on the part a pretreat is required. For steel iron phosphate works good. If you skip this part the question is not if the coating will fail but rather when, as it will fail in time. Once it starts to peel there is no stopping it. It is then a real pain to remove for repaint. Generally you will need to media blast, run it through a burn off oven, or chemically strip it to get it off. Cure: in order to cure powder properly time in the oven is very important. Lets say that the powder you use requires 350*f for thirty minutes. Okay, now you have powder on your part and you go into the oven, the cure time does not start when the part goes into the oven. It starts when the metal reaches 350*f. how long does it take to get the part to 350? Depends on the thickness and size of the part. Some parts will come up to temp in as little as five minutes while one that is �� or even 3/8� of an inch thick may need to be in the oven for thirty to forty minutes before the metal is at the temperature where you can begin counting cure time. If you over cure you run the risk of burning the pigment in the coating and it can change colors. Any chromatic color like red�s, yellow�s, and some whites can do this.
We use a data tracker that has a temp probe attached to a discrete area on the part that we can monitor form the outside. Now we know exactly when the part is at temp and we can begin counting cure time. Here again if the cure on the powder is not correct it is not if but when the coating will fail. Durability: powders are very durable if the above are all met along with the proper choice. I have seen many times where someone will apply a powder the is not meant to be outside and then it goes out. After only a few months it starts to fade, peel, and get chalky because the particular powder does not contain any UV package to keep the sun from beating it up. If you can meet the requirements for prep, cure, and choice of powder you will like the end result. If you cannot you are better off going liquid as it is much more forgiving. Can�t comment on the powder coating machine you mentioned. Most of the small hobby type coaters work fairly well as long as they are not pushed beyond their intended limits.
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