Nickel rusted after getting wet

[FOMOCO78]

I plated some bolts for my truck using the electroless nickel kit some time ago. I noticed after they got wet that some of them had flash rust on them. Prior to plating i cleaned them on bench wire brush then polished and cleaned them with laquer thinner pior to plating. Should i have soaked them in a pickle solution first? After plating them the plate looked OK and polished up nicely. I also think I may have contaminated the batch by using metal tag wire instead of cotton string. And lastly can I use electroless chrome over the nickel after I redo them in nickel. ?

[mcaswell]

Difficult to say exactly what caused the rusting.

1. Insufficient surface prep.
2. If you acid etched, then insufficient rinsing
3. Not plated for long enough time (I'd bet this one)
4. Parts to large for volume of solution. Watch maximum loads

Give us some more data, please.

Yes, you can use E Krome over, but etch in battery acid to activate the nickel first.

The steel wire wouldn't have caused the problem.

[FOMOCO78]

More info

OK the bolts were rusty, I power wire brushed them on a bench wheel. DID NOT ACID TREAT. Used a soft tagging wire that Ironworkers use to tie rebar, I noticed that these bolts came out much darker than the ones I used string on, Also shortly after i replenished the mix becasme a milky color but seemed to plate OK other than I had to polish them a little more, I figure I either depleted the mix or contaminated it with what ever that wire has in it. Definitely had them in the mix long enough and added distilled water as it depleted. Your input is appreciated. Thanks!