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  for Metal Finishing since 1989
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How long can you wait before painting after your phosphate treatment is completed?

We are sending product out to be phosphate treated and they are sending them back so we can paint them them in house. Is there a time frame I should be aware of or any problem that I might run into?

Brad Karie
ComtectEFData - Tempe, Arizona, USA
2006

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2006

Time is dependent on conditions of storage and transport. The main problem that you will encounter if you leave the parts too long before painting is corrosion. Phosphate itself does not offer much in the line of corrosion protection. Some phosphates call up a chromate seal, which improves corrosion resistance, but still does not offer good corrosion protection.

The sooner the parts are painted the better. If there any signs of corrosion then you will need to strip the parts and start again.

It is difficult to give definitive times but I would try to get them painted within 24 hours if possible. If the parts are stored and transported in hermetically sealed plastic bags (polythene is preferable, or maybe I'm just being fussy) then you can probably get away with 48 hours, but you really don't want to be going much longer than that.

Brian Terry
Aerospace - Yeovil, Somerset, UK