Electroplating (zinc)

[Chris Stevens]

Wonder if anyone has experience of BZP plating? Just need to do small bike parts, spindles, nuts and bolts, brake cams etc. Did have a very good place locally that did a good job at the right money, but they dont do BZP any longer, so rather than risk someone else losing things, bought a BZP kit.

Would be interested if anyone is using a basket of some sort to put parts to be plated in, rather than wiring all individually, and whether there is a need to remove original BZP on parts before they are plated again?

Wonder if the following would work ok (parts are all degreased and relatively clean): First electro clean to remove any rust, grease, paint, swill in clean water, acid pickle dip, swill clean water, plating bath, swill clean water, passivate, swill clean water, dry?

Lots of stuff on the net about plating, but difficult to work out whats most effective, and those selling the kits seem more interested in selling small amounts of chemicals at high prices, than providing any info about the best way to go about plating more common items.

 

[Mr shiney]

I have been using one on bike parts and other stuff that I make on the lathe for a few years. Results have been excellent. The quality of the finish is only as good as the quality of the part and the preparation you put in. Cleanliness in critical.

Look up some of my posts as there are quite a few pictures on the forum of stuff I have done.

 

[Chris Stevens]

I have been using one on bike parts and other stuff that I make on the lathe for a few years. Results have been excellent. The quality of the finish is only as good as the quality of the part and the preparation you put in. Cleanliness in critical.

Look up some of my posts as there are quite a few pictures on the forum of stuff I have done.

Thanks................do you think what I have suggested re process in my post will work ok?

 

[Mr shiney]

You can plate over old stuff, just bear in mind the finish will reflect exactly what the surface looked like in the first place. Zinc does not hide a poor finish.

I use alkaline cleaner before a pickle. Cleanliness is next to godliness when it comes to plating. Only touch with gloves during and after cleaning. I rinse in distilled water.

A basket is no good as it creates hot spots on the item and poor electrical contact. Wire it and only do a few items at a time if they are small or single larger items. This is not a bulk system, it's painstaking and time consuming. If you accept this you get amazing results. I can get a well prepped item to look like it's been chromed.

 

[Chris Stevens]

Ok thanks. Electrolytic cleaning no good then? How would I go about removing old zinc?

 

[Mr shiney]

Acid. I have a gallon of the stuff but it takes ages to do and can often damage the source as well. Stuff gets zinc plated for a reason!

 

[Wallace]

Brick acid takes the old plating off, diluted hydrochloric acid.

 

[Chris Stevens]

Thanks

 

[Wallace]

Which kit did you buy? I started out with a Classic Plating kit eventually sourcing better quantities and information from elsewhere. Drum plating is possible at home, this guy has some good info on his website of a small setup. Have you tried black passivate?

 

[Mr shiney]

I use a variety of passivate including the black and the military green. The black needs the item to be clear passivated first and then done in black to stir properly and it's not a true black like you see on impact tools it's quite wishy washy!!

I started with the classic kit as well and now do the same as you and source the chemicals individually as it's cheaper. It was a great introduction to the kit and it's been worth every penny.

 

[Wallace]

Best I ever achieved with the black was a dark brown and one of the first pieces went outside to weather and still looks the same today. I had a long chat with a supplier who was open and honest about the black and would only sell it if you understood how difficult it can be. The olive green has given me the best results for colour with a wear resistant finish. A before and after, the casting was die cast zinc:

(Click to enlarge)


Before......


......After.


Zinc & clear on the steel fixings

 

[Chris Stevens]

Which kit did you buy? I started out with a Classic Plating kit eventually sourcing better quantities and information from elsewhere. Drum plating is possible at home, this guy has some good info on his website of a small setup. Have you tried black passivate?

I have Classic Plating kit, which I guess provides a good but quite costly introduction to home plating? In terms of plating several parts at a time, then maybe a drum made of Ti gauze would make for better electrical contact than plastic and hit or miss contact system?