Powdercoating stock A-arms. Pappy?

[wilkin250r]

This isn't the normal "Can I do it, what would happen?" thread. I've heard about a procedure that uses infrared light to bake the powdercoat, rather than an oven.

With infrared light, you can selectively heat certain areas, while leaving other areas alone. It would seem that you could mask off the ball joints, and only bake the powdered areas, leaving the ball joints relatively cool, and thus leave them undamaged from the heat.

Pappy, as our resident PC expert, can you shed some 'light' on this? (pardon the pun)

[quadrcr161]

im not pappy and i could be wrong, but the powder had to hit 350 degrees to cure, and what ever touches the part being heated will also get hot, such as the pall joints. another thing when i powder coated a valve cover for my car, i thought i had all the oil and greese off but it still smokes some and put some blems in the PC. i think it would heat up too much, mess up the greese and rubber boot and not cure on the piece right.

[wilkin250r]

True, metal is a pretty good conductor of heat. But it doesn't happen instantly. If you can heat the powder and surface quickly enough, you can prevent the ball joint from overheating.

I know doing oven reflow in electronics manufacturing, there is often as much as 100 degrees difference between the surface of the part and the inside of the part, because it is exposed to very high heat for a brief period of time.

[quadrcr161]

there might be a way to do it, but im not sure. i know a guy doing the frame of my old 300ex put the lamp to close and burnt the powder, and it didnt cure right by useing the lamp. it would flake off like paint.

[Out_Sider]

pappy says it is not possible to pc stock arms because of the ball joints

[zephead400ex]

I believe (and do not mean to undermine) what Wilkins is saying is that it is possible to heat only the arm, not the ball joints, therefore allowing pc to be applied without heating the ball joints. Maybe using something like a hand held too instead of an oven.

Maybe something like the tools that DDS use to cure the apoxy used to fill cavities. It uses infrared light at a specific temperature to only heat what needs to be heated. In this case it would only be the metal, not the ball joint.

[wilkin250r]

Originally posted by zephead400ex
I believe (and do not mean to undermine) what Wilkins is saying is that it is possible to heat only the arm, not the ball joints, therefore allowing pc to be applied without heating the ball joints. Maybe using something like a hand held too instead of an oven.

Maybe something like the tools that DDS use to cure the apoxy used to fill cavities. It uses infrared light at a specific temperature to only heat what needs to be heated. In this case it would only be the metal, not the ball joint.

Exactly. By using infrared light, instead of an oven, you can selectively apply heat to ONLY those areas that are powdercoated. Sure, the ball joints will get warm, because the metal will conduct heat, but they may not reach the full 350 degrees, and thus not be damaged from excessive heat.

[Out_Sider]

hmm, you have a point there, i guess pappy was jsut tellin me about doin it in an oven, i talked to him a month or 2 ago about it, but then i got my aftermarket arms.

[K_Fulk]

The powder has to be at 400 for 15 minutes ( temp and time varies to diffrent powder? Being at that temp for that long its gonna absorb into the balljoint.

The average infared lamp dosent work that great either. Parts usually still get undercured anyway.

If it was me I would either paint them, or do like ugly mother did to his stock 400 a-arms, and add some removalbe ball joints.

[250rAL]

How about hanging the arm in front of the lamp with the ball joint in a container of water?

[FoxRacing81]

Hmm...strange...because my friend had his stock a arms on his z400 powdercoated so theyd match his frame.

[Pappy]

its not an issue of "can it be done" but rather "should it be done"

the stock ball joints use a nylon/polymer locator/cushion and if properly cured it will melt and when cooled it becomes brittle.

using a heat source of any type to bring the metal (not just the powder) to a cure temp of 330 to 400 degrees for a cure time of 15 to 30 minutes will harm the ball joint.

i have tried them, i have seen them done with both success and failure. i personally have never heard of a ball joint failing due to the arm being coated but just knowing its a possiblity is enough for me to turn the other way when someone wants them done.