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Acetone wipe test for Anodize

2003

I have a customer who requires an acetone [on eBay or Amazon] wipe down test on the products that they have anodized to MIL-A-8625 / MIL-PRF-8625 [on DLA],Type III, Class 1, Teflon Impregnate , Black. They take a cloth or paper towel and cover it and the part in acetone, they when wipe down the part to see if any color comes off on the cloth or paper towel. My question is, if a part is anodized to this spec will it pass the acetone test each time or does the spec allow some color to be wiped off?

Thanks,

Allen Leath
medical equipment supplier - Lynchburg, Virginia, US

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Hello,

The spec. you're asked to perform is incorrect. MIL-A-8625 / MIL-PRF-8625 [on DLA] Type III class I is a non-dyed, Hard anodize. Class II would be colored. If what your customer needs is a Class I coating with a thickness in the range of 2 mils. They should expect the part to be near black due to the effect the coating has on the substrate in the formation of the anodic coating. In this case it should pass the before mentioned test due to the fact that no dye has been introduced.

But, if they really desire a dyed (class II) coating then the parts should be sealed (Teflon® is not a seal) after dye if you want it to pass this test. Keep in mind that sealing a hard anodic coating lowers the abrasion resistance by as much as 30%. Further more I would think rubbing the parts may remove some of the Teflon®?

good luck!

Bill Grayson
metal finishing - Santa Cruz, California
2003

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The fishing reels that I anodize used to be Type II but to 2 mil thickness. I clean them down after sealing with acetone [on eBay or Amazon] all the time and the colour never comes off. Yours shouldn't either if the parts are sealed correctly. If it's not sealed properly, then it sometimes has a 'tacky' feeling about it. If this is the case, send it back and let them re-seal the parts. Just for info, my parts are not etched when being anodized.

Michael Georgiadis
- Durban, South Africa
2003