Nickel Plating Brass

If this has been covered before I apologise.

I have a project in brass that I wanted to nickel plate to improve the looks. I bought a bright nickel kit from Gateros and with some trepidation set about experimenting with it.

The kit has excellent notes and contents with it and comes with sufficient material to make up a 5 litre bath with a matching number of nickel anodes. I didn't need a 5 litre size bath so I mixed the full bath quantity and then used this to fill a larger kilner jar into which I dangled two nickel anodes on the platinum wire provided. I made a totally over engineered rig to suspend the anodes and the parts but that is another story.

The kit also contains an acid pickle mix, again for 5 litres worth. I repeated the process and sub filled a kilner.

The excess mixes have gone into storage for later topping up.

I have a 5 litre ultrasonic cleaner with heater and timer. I set the heat to 40 degrees and put the pickle kilner in the tank surrounded by water. I also added a second kilner filled with dilute Cussons Clock Cleaning fluid.

The plating kilner sat separate to the tank connected to my bench power supply. Initially I did have the plating jar in the ultrasonic bath so the fluid was kept warm but the ultrasound vibrations caused erratic connectivity to the copper wire connections to the parts being plated. In the end to maintain a warm temperature in the plating fluid I gave it an occasional ping in the microwave while 'management' weren't watching.

Process : -

Clean the part as best possible and finish with fine wire wool to get a bright finish. Dust off with the air line. Note that screw threads and knurling are impossible to clean but the next stage in the CCCF seems to overcomes this.

Dangle the part in the CCCF using copper wire hooked over the side of the jar. Ultrasound for 5 minutes at 40 degrees (ish).

Rinse well in warm water otherwise condensation appears on the part.

Dangle in the pickle solution for I minute with ultrasound on.

Rinse well once again in warm water and dry on a paper towel.

From this point on do not touch the part with your hands or contamination of the cleanliness achieved will mar your end results.

Dangle the item in plating solution for 20 minutes with the solution warmed to around 30 degrees. The jar is separate to the tank so no ultrasound but an occasional waggle of the part seems useful.

I need to qualify the set up a bit better. My kilner has two anodes, one on each side of the jar which are approx 3" apart. The current limit on the power supply was set to 100 mA for small parts and a bit higher for larger surfaces areas. Note that Gateros recommend 120 mA per square inch. If you overdo this the parts start to bubble and any sharp corners will start to show burning of the plating.

Don't load the bath with parts, up the current and then remove them one by one as the last one to remain gets the full dose and burns. Best to switch off while loading and unloading.

Note also when plating screw threads to move the copper suspension wire along the thread about half way through plating to avoid an annoying mark on the thread.

The results have been remarkably good with a high lustre finish with no distracting defects visible.

If of interest a more detailed blow by blow might be worth a write up in MEW.

Alan

Ideally the parts for Nickel plating should be Copper plated first, this seals up any small pits etc. Then Nickel plate.

A cleaner I have used is called Zonax, Not sure where to get it now though.

Clive

My understanding was that brass already contains copper so why would you pre-plate with copper ?

Because brass is an alloy with zinc - a relatively reactive metal. So a coat of pure, less reactive copper helps.

Cheers, Tim

In the deep and very distant past I remember being toldt,on a school trip around "The Works " at Wolverton that the standards for BR plating was for nickel , copper then nickel , inspection , 2nd Nickel . For Chrome , copper , Nickel , Chrome , inspection, 2nd hrome. Could explain why the handles on 60yr old coaches still have chome on them !

Brian C

2 points.

Copper is very soft so it's very easy to buff to a high lustre, then plate the nickel over for a good finish.

I have nothing but praise for Gateros.