sm96785
Mechanical
- Apr 2, 2014
- 4
Hey,
This seems like a relatively simple question.
A product we are having made in China is a A36 Steel Plate that is stamped/formed and then needs a black texture powdercoating.
My drawing just stated "black texture powder coat". The samples I got were good, but the production parts were not nearly as good.
I had really nothing to argue against since my specs were not very defined.
The steel plates bolt onto the inside walls of pickup trucks for additional tie-down points. About 4x4" and 1/8" thick.
They need to be UV resistant and generally should not rust for 10 years. They are not exposed to corrosive elements. They should not easily scratch or chip since they will get knocked into from time to time as you would expect.
I recently added a vibration tumble process before coating to remove sharp edges so that the coating will stick better. Is there a spec callout for vibration? Media size, grit, duration?
I would like to have an e-coat applied before the powder coat. What is the callout for e-coat requirements? Do I have to specify the cleaning process?
Finally, for a black texture powdercoat finish, how do I call that out? How to I specify the thickness, the corrosion resistance, etc. There are different types of powders, which type is best for my application?
The parts are simple and in my opinion the coating does not require extreme resistance. I just dont want it to show signs of color fade or rusting with normal use of say 5-10 years and that it should not easily chip off. Some customers have noted that their parts are rusting within just weeks of installation. Clearly not what I expected.
If you have any advice on what specifications should be called out on the drawing I would greatly appreciate it, I could not find anything online. I used to work for John Deere and I recall they have e-coat / powder coat specs but I think they may have been internal specs.
This seems like a relatively simple question.
A product we are having made in China is a A36 Steel Plate that is stamped/formed and then needs a black texture powdercoating.
My drawing just stated "black texture powder coat". The samples I got were good, but the production parts were not nearly as good.
I had really nothing to argue against since my specs were not very defined.
The steel plates bolt onto the inside walls of pickup trucks for additional tie-down points. About 4x4" and 1/8" thick.
They need to be UV resistant and generally should not rust for 10 years. They are not exposed to corrosive elements. They should not easily scratch or chip since they will get knocked into from time to time as you would expect.
I recently added a vibration tumble process before coating to remove sharp edges so that the coating will stick better. Is there a spec callout for vibration? Media size, grit, duration?
I would like to have an e-coat applied before the powder coat. What is the callout for e-coat requirements? Do I have to specify the cleaning process?
Finally, for a black texture powdercoat finish, how do I call that out? How to I specify the thickness, the corrosion resistance, etc. There are different types of powders, which type is best for my application?
The parts are simple and in my opinion the coating does not require extreme resistance. I just dont want it to show signs of color fade or rusting with normal use of say 5-10 years and that it should not easily chip off. Some customers have noted that their parts are rusting within just weeks of installation. Clearly not what I expected.
If you have any advice on what specifications should be called out on the drawing I would greatly appreciate it, I could not find anything online. I used to work for John Deere and I recall they have e-coat / powder coat specs but I think they may have been internal specs.