flash copper

[fullthrottle24]

Iam still having a problem with the flash copper, now my problem is plating the alum , i zincated the part, then tried to flash copper the part for about 20 minutes, some parts of the piece were fine the other parts were flaking off, some spots were almost black like it was burnt, and also when plating plating alum, what is the best steps? flash copper, nickel, then chrome?? or do i need to flash, then bright copper, nickel, then chrome?

[ashcroft01]

fullthrottle24,

From my experience, nickel will plate directly to a zincated piece of aluminum without the need for a copper strike coat. Copper could be used for filling in slight imperfections in the base metal, but a mirror polished piece of aluminum properly cleaned should take nickel and chrome beautifully. Caswell's suggests that you Zincate first, then Nickel, Acid Copper, Nickel again and Finally Chrome for a true triple chrome plate finish.

It sounds as if the black deposits you were experiencing may have been surface contamination on the aluminum. I restore a lot of antique silver plated pieces and some of the base metals I deal with (Pewter, Britannia Metal, White Metal, Pot Metal, Aluminum, etc.) will streak and flake from time to time in the Flash Copper. Sometimes it is impossible to get the surface clinically free of corrosion the very first time. It takes a lot of media blasting, polishing and de-greasing to make it all stick.

Best of luck,

Curtis

[lcaswell]

It's actually best to Zincate, Flash Copper, Nickel, Chrome. If you plate zincated parts directly with Nickel, your nickel tank will eventually get contaminated with zinc, and you'll need to dummy plate it out.

If you Flash Copper is peeling or flaking, the part wasn't clean enough. If it's burning, you're likely hitting it with too much current.

Without more details on your part and current used, we can't help much more than that.