Questions relating to finishing processes

Sure any 'finishing process' that cleans oils and soils off the substrate, be it black iron [steel], stainless steel, alloys, aluminum w/conversion[?] can be used...BUT the results desired, that is, a way to make the paint stick to the substrate may not be achieved in the long run. Specific substrate require specific pre-treatments. Generally speaking.

Note that a phosphate applied to stainless steel and some alloys is not going to do much to make paint stick to this substrate. Other pretreatments are better for stainless steel.

Two questions that need to be answered first.

Painting the work [finishing the substrate]...lets say it is black iron [mild steel].

#1~For a 'point-of-purchase' display. You don't care if the paint falls off after the item is sold. After market automotive shock absorbers for example.

#2 Painting the work for a 'warrantied finish'. You warrent the finish to remain on the work sold for X amount of time. Original automotive shock absorbers and home laundry washers and dryers for example.

In other words, "How good is good?" in terms of this;

"Paint does not stick to steel. Phosphate [or conversions] stick to steel and paint sticks to phosphate."

Iron phos provides some adhesion. Maybe 150 mg per sq foot. Zinc phosphate provides more adhesion. Maybe 300 mg per sq foot, simply because the zinc is going to 'suck up' and require more paint to cover the phosphated work. It's my crude and nonscientific explanation but do you understand?

Your turn.

Please tell us more about what your doing. Thank you.

skip.

Last edited by skip (02/04/2010 - 03:14 PM)