On powder coating spring steel

[Mac Thamhais]

Greetings good milords.

I had a question concerning the powder coating process. Is there any heat involved in it, and if so how much? Basically, what I am wondering is whether or not it is safe to powder coat a piece of properly hardened and tempered spring steel. I know that too much heat applied to a heat treated object will take the temper out of it, but I don't know whether or not the powder coating process involves enough heat to do this.

Thoughts, comments?

[Louis de Leon]

Found this page on powder coating.

He says:

Almost any metal part than can be painted, can be powder coated, with a few caveats. In order to use powder, parts must be able to withstand the curing temperatures of powder. This usually means 350°-450°F for 15-30 minutes.

I know that's low enough not to fiddle with the temper for 4130 too much. 400F for a half an hour would probably be ok. You'd probably lose a tiny bit of hardness but I think it would work. If you were really worried about it you could do less secondary heat treatment to prepare for the hardness lost to the powder coating process.

To heat treat 4130 you heat it up to orange, quench it in water, then do a secondary heat. The secondary heat is to make the piece lose some hardness and not be brittle and relax the stresses built up in the piece during the quench. I go 500F for a half an hour. At the end the piece comes out of the oven a nice purple. So if I was going to powder coat something, I'd switch my secondary heat to maybe 500F for 20 minutes. Then powder coat cure at 400F for a half an hour. That'd probably work ok.

Other alloys though like 1050, I don't know much about.

[Johann Lederer]

Not to derail the thread, but I am wondering how brittle the powder coat is once it is on. Do you think it getting hit with clubs or metal would make it chip off?

[Lorenz De Thornham]

That is what I was thinking, also once it cracks, that is the end usually as moisture gets in and it is a great environment for rust.

[The Iron Dwarf]

it would certainly chip and scratch, dont know about flaking due to bending at the edge of dents and it cant be touched up like normal paint can.
electroplating the item first would prevent rust but a chip or scratch can only be repaired with a normal type of paint IMO.
I often get other stuff I make zinc plated and then yellow passivated, also you can get black and a silver finish, here it is not expensive but there is normally a minimum order ( where I go it is about 45 uk pounds )

[Mac Thamhais]

Powder coating may chip or crack on moving parts where there is metal on metal contact (ie - articulated knees and elbows.) On non-moving parts however, it is damn near bullet proof. I sent my helm out and had it powder coated the second I got it from the armorer, and I've worn it ever since. Now my fighting kinda sucks, so I get hit in the head A LOT! The powder coating has never showed even the slightest hint of wear. It doesn't chip, it doesn't crack and your helm is permanently rust proof. All you need do is occasionally wipe off the tape marks left by other peoples weapons. I fully intend to have powder coated every helm I own until the day I die.

[The Iron Dwarf]

over here every event I have been to the battles have always been using metal weapons, I know there are many other types of event here and do not know what sort of fighting you did

[Mac Thamhais]

good point. I have never used my powder coated helm with metal weapons (nor do I intend to )

I admit, that would be a whole nother kettle of fish.

[Steinolf]

The horse had a very good article on doing this at home.

http://www.ironcross.net/back%20issues/number76.htm

[Lienhart Fischer]

a bunch of the guys around here have powder coated helms, i've seen some pretty serious dents and no one has flaked off a piece yet

they seem pretty scratch resistant too,a basket hilt to the head peels off some of the coat but not down to metal