Thanks for the comments guys, IW ,i have a small blast cabinet which removes the rust or existing zinc plating, i then wash the item and acid dip for a minute
Here are some tips which i posted on another site
Hi all i have had lots of questions regarding zinc plating and if there are any tips i can give for doing it at home
So here are my tips based on my experiences, please bear in mind i am not an expert , i just enjoy restoring these bits myself, infact if you go to the right places with a job lot of parts to plate it can work out cheaper than doing it yourself, however for me its all about the enjoyment of doing as much as possible myself on the bike restoring , and the convenience of being able to do random parts when ever i want
First thing is to buy a zinc plating kit, i buy all my stuff from gateros plating,
http://www.gaterosplating.co.uk/ they are in my opinion the best out there, i will give you an example, i bought a kit from them set it all up , and started plating, i had some really bad results and asked them by email for some tips as to what i was doing wrong, Dan at gateros plating responded to my emails really quickly and talked me through step by step what i should be doing, and also asked me exactly what i had done so he could pin point what was causing my problems, anyway he established that i had contamination in my chemical bath, i have no idea if it was down to me or not but without me even asking he kindly sent me some new chemicals so i could renew the plating bath, and also some new zinc anodes all free of charge, now i have to say in this day and age that is top notch customer service, and for that reason i will always use and recommend them.
OK when you get your kit ( i use the Zinc/ Nickel kit as it gives better protection) read all the instructions, then read them again and try and get a good understanding of the process, follow it all by the letter don't cut any corners,
Here are the things I recommend you get which are not in the kit, an Amp meter and a box of 100 latex gloves, and several large new clean buckets
Get set up on a decent stable work surface with plenty of room, set everything up as instructed then add your amp meter into the electrical circuit so you can monitor the amps going into the process, this is critical if you ask me as to many amps in relation to the size of the piece to be plated will burn out the brighteners in the solution, and use up the zinc really fast, it also turns the zinc a sooty black colour which has to be cleaned off,
Work out the area of the item to be plated, don't guess, measure it , if for example you are doing a long engine bolt get the length, then wrap a piece of string round the circumference and measure that sting to get width, then x length by width to give your area, i am getting good results at between 80 and 100 milliamps per square inch, i would not recommend going over 100ma per inch
There are many very important things to get right in the process another one is cleanliness, be prepared to use up lots of disposable gloves, as contamination of the various chemicals and parts is easily done, example if you have the same gloves on that you have just passivated a plated item with and you proceed on to plating another piece you will find just touching the newly plated part with your passivate contaminated gloves will give horrible black marks to the zinc which set you right back, have rinse buckets of fresh water available, use a different bucket for each dip, example, when you rinse the freshly plated item and then passivate, use a different rinse bucket to rinse of the passivate, you have to eliminate all potential cross contamination, ideally have a dedicated sink for rinsing, if not several buckets of clean water and change them after each session
The temperature is also very important , this applies to the plating solution and the passivates, keep them to the recommended temperature, using fish tank heaters
Agitation is very important, some of the kits come with a fish tank air pump which you can use to keep the solution agitated, or you can stand over it gently moving the solution, whatever the method don't ignore this as it all plays a part in getting good results
Keeping the solution clean, again this a must, some kits come with a fish tank filter, but they awkward , and get in the way, what i do now is use an old coffee jug and paper filters, and after every session i filter the solution and return it to my storage tank all clean & ready for its next use.
Keeping the Anodes clean, this also needs to be done , wash them thoroughly and hang them up to air dry , or dry them quick with a hot air gun, the connection from your wire to the anode often gets all firred up and so you could potentially be hanging an anode in the solution which is not making an electrical connection, soldering them is an option or just making sure by that the wire and anode is bright metal and getting a good connection
Properly preparing the item to be plated is of up most importance, you will not get good results unless you do the prep right, ideally you should blast the items in a blast cabinet, but whatever your method it will need to be rust and grease free, degrease as detailed in the kits instructions , don't cut corners here or you will regret it
Time in the solution, i plate between 20 Min's and 1 hour depending on the item, if it is say an item that is going to be down there by the wheels and getting lots of road salt then i give it anything up to an hour, other bits 20 Min's is enough and probably equal to the factory finish
Have plenty of new clean copper wire, and when you reuse the old wire, rinse it off ,get a scotchbrite cloth brighten up the wire again, i have a reel of old twin and earth i just strip the plastic from it and have a big supply of fresh copper wire , you will find you get through loads
Work in a ventilated area, if you are doing it in your shed or garage, beware that any items of chrome you have might get marks on, IE don't do it next to your pride and joy restored bikes or items as the fumes in the air seem to mark chrome, this is just my experience , and a painfully learned lesson
To recap above
Buy kit
get additional items , gloves , buckets or sink, blast cabinet, coffee filters, amp meter, additional tank heaters, copper wire
Follow instructions with the kit to the letter
Keep everything clean, rinsing, washing anodes, filtering solution etc
Accurately work out the area to be plated
Control the amps, between 80and a 100 ma per square inch
Use different gloves for different stages
Work in a ventilated area, and wash your hands as often as possible
One last tip, the best results are in spring summer when the outside temperatures are 15 +, i find good results harder to get in the winter months regardless of heaters, it takes allot more messing around in the cold, good results are still possible just harder
Hope this of help to anyone thinking of doing it
Pete
