Couple Copy Cad questions

[aermakov@rogers.com]

Hi. I am a proud owner of your Copy Cad kit, very happy with it BTW. Have a few questions.
1. Commercially obtained fasteners are usually zinc plated and then clear chromated. Is there an effective CHEMICAL way to remove the the factory chromate finish in order to replate an then Yellow or Black chromate these nuts and bolts. Re-plating as is produces very dull and rough finish, glass beading solves it, but is very time consuming for a large number of small new parts.
2. Is it safe to use Muriatic acid for rust removal, prior to plating, on parts that have metal and rubber components, brake hoses for example. I am concerned with rubber portion of the part how is it affected. Burst brake hose could be unpleasant.
3. What are the signs of aging Yellow chromate? Lately, I am still getting the color required, but few minutes in hot water (to stop chromating process) wash off almost entire yellow color.

[mcaswell]

1. Dipping in an acid pickle will remove the existing zinc plate. See the section in the manual on acid pickles.

2. It depends what the metal is. If it's die cast, then NO. The acid will attack the part.

3. It should last a very long time. Try plating a thicker layer of zinc.