This article was written by Steve Cooper, Journalist, Motorcyclist and active member of the Vintage Japanese Motorcycle Club for inclusion in the  August 2008 issue of CMM.  The words and pictures have not been changed and have been portrayed in the manner intended.  Caswell Europe wish to thank Steve for being allowed to post this article on the web and also to thank Classic Motorcycle Mechanics (Morton's Motorcycle Media) for their joint agreement.

Introduction.

During any restoration there comes a time when parts need refinishing. Most restorers try to do as much spannering as possible, some have the facilities and skills to paint but most of us elect to contract out plating, after all it’s a cheap as chips. If you don’t have a zinc plater locally or have had parts lost or damaged in the past you might want consider doing the job yourself. This month we look at a typical kit from Caswell Europe, a name familiar to some readers. So without further a do its gloves and goggles on, sleeves up and get stuck in!

 

Basic Kit & Sub Units~ The plating kit comes as a primary unit for zinc or copy cad and includes the necessary tank, heater, two part plating salts, zinc anode sheet and an abrasive wheel which is used to mildly abrade cleaned steel to replicate cadmium plating. It's no longer permissible in the UK to plate with cadmium due to its inherent toxicity so this part of the kit allows you to replicate that “olde worlde” cad finish. Also pictured are some of the sub kits that allow complimentary additional finishes. Covering most of the bikes featured in CMM we should be able to replicate zinc, yellow and olive drab passivate along with blacking.

 

 

Additional needs + H&S~ Although not as dangerous as battery acid we are dealing with chemicals here so gloves and safety glasses are the order of the day. Also needed are some insulated wires, a 1.5v battery and holder, copper wire and a conductor for mounting our parts off. Here I’ve used a piece of folded copper sheet and some brass screw connectors but a piece of 15mm copper pipe and some copper wire are fine. Also advisable is an RCD as we’ll be heating up the plating solution. Finally, before we jump in with both feet it’s time for a brew and RTFM (read the flipping manual).

 

Mixing the brew ~ It’s important to remember that the quality of the plating solution is paramount to the finish we’re hoping to achieve. Anything that comes in contact with the plating solution HAS to be clean and that includes everything, heater, tank, components etc. Here I’m stirring the freshly made solution with a piece of clean plastic pipe. Borrowing the wife’s wooden spoon from the kitchen is not an option. When dissolved a few drops of zinc brightener are also added to the tank as we’re looking for a nice sharp, clean zinc finish. If the results are too bling I can dull them off later.

 

 
Removing old plating ~ Before it’s time to play with the plating kit we need to remove the old plating. There are a number of options but realistically chemical or abrasive removals are the only viable way. I prefer to chemically strip the old plating off and here I’m using some “brick acid” or patio cleaner. A 50/50 dilution gets the old zinc off quite quickly but remember to wear gloves and goggles. The same applies if you opt to grit or sand blast. Trying to remove plating with a rotary wire wheel is hard work and often only seems to toughen the zinc to steel bond, not what we’re hoping for, thank you! Once the zinc is off the bare metal is exposed so ensure it doesn’t get damp and starts rusting.

 

 

 (a) Cleaning &………  If the devil is in the detail this is where Beelzebub resides. The best plating in the world won’t overcome poor preparation. The steel really benefits from being cleaned and polished to varying degrees. I’m starting off here with a rotary brass brush in normal drill; a steel brush may be necessary for more badly corroded parts but for these fitting brass is fine. Goggles and good gloves are needed here. Holding small parts can be difficult so invest in few pair of cheap pliers or Mole grips. Once you’ve fired a handful of irreplaceable, pre ISO, float bowl screws around the work shop you’ll understand why!

 

 

(b) ………..& Polishing ~ After a quick whiz on the wire brush it’s time for a buffing session. Here I have a sisal, medium and finishing mop and the relevant compounds. For most fittings on Japanese bikes a sisal and medium mop are all that’s needed. Included in the kit is a nylon brush which is used to mildly scarify the cleaned steel surface and plating over this with zinc  gives a very good facsimile of old fashioned  cadmium plating. After polishing remove any polishing compound and wash the parts with methylated spirits or similar. Realistically all this cleaning and polishing is what you do before handing over your precious parts to a plater as very few will do this for you. If they do clean it’s often only a cursory job,

Ready to plate ~ OK it’s nearly time to play with the kit and see what’s what but before I flick the switches and play Baron Frankenstein I’m checking all is ready. The heater supplied has heated the solution as per the book (read plater’s bible) and I’ve wrapped the tank in some bubble wrap to conserve heat. I’ve secured the anodes in place with plastic clothes pegs stolen from Mrs. Cooper’s laundry logistics department and I’ve checked my wiring and polarity. My trusty multi-meter is on hand to help if I can’t quite work out what I’m doing.

 
 

(a) Plating ~ I’ve wired the components up to the cathode with some copper wire; remnants of used twin and earth domestic cable proving to be ideal. Lower the components into the solution, connect the battery and cry “more power Igor”. OK perhaps not but it’s really satisfying seeing the reaction start. No fizz and you either haven’t completed the circuit, the battery is dead or the component is physically too big for the power available. If you get an Alka-Seltzer reaction there’s too much power or not enough components. You need to balance power against surface area. Check the manual!

 

 

 
(b) Plating ~ Here’s the finished result after a few minutes and fresh out of the plating tank. The actual process took less that ten minutes and I’m very happy with the results. A quick rinse with some deionised water removes the residual solution and I allow this back into the plating tank to minimise losses. Dry the components off with kitchen towel and store or fit as desired. If I’m not ready to use these nice shiny parts I wipe them over with ACF-50 and store them in a plastic Chinese take-away dish. All this renovating and re-use of disposable packaging!
 

Before and after ~ Well here’s the evidence and it looks very convincing for a beginner. The results more than speak for themselves and there’s little doubt the kit works and works well. Whether it’s cost effective depends on your needs, commitment to learn and the rarity of your parts. I have some choke linkages off my 1967 Yamaha YCS1 and these are scarce in the extreme but now I have the resource to refinish them without worrying about whether they’ll get lost or mislaid. On that basis and these results I’m more than happy to use the kit and would say that anyone who can carry out basic maintenance can use this system without any worries.  

Yellow Passivate ~ Many Japanese bikes have components that have an additional level of protection over and above the zinc plate. The classic iridescent yellow finish found on many components from the 70s on can be replicated with one of the sub kits supplied by Caswell Europe. It’s a simple dip process on fresh or cleaned zinc carried out at the proscribed temperature. Here I’ve treated a washer and part treated a bolt so that you see the comparative difference.
Green passivate ~ As costs rose in Japanese manufacturing many suppliers adopted a green passivate process that was quicker and more economical. Again another sub kit can be used to generate this effect. Yamaha LC owners in particular will be pleased to know this finish is available. With time patience and ingenuity it’s quite possible to refinish bottom yokes, break pedal, case screws etc at a fraction of NOS parts (if you can find them!) Initial appearances may be a little on the pale side but a quick wipe over with some ACF-50 brings out the colour quite nicely. Caswell Europe is talking to their USA principles regarding the best they can duplicate this very specific Japanese finish. Not many suppliers in our world are prepared to do that!

Blacking ~ Finally the last of the sub kits evaluated allows an authentic and durable black finish to be obtained. Case screws, hose clips and range of smaller components often have this finish and this kit effects a very good cost effective protective coating to be applied. Using the protective sealer also available for use with the blacking kit I can add a bit of sheen to the blacked fasteners and increase corrosion resistance. I’ll be using this same kit on some unobtainable carb clips for another project soon without any qualms.
 

Conclusion~ Starting off as a novice with no real idea of plating I’ve managed to recreate a range of protective finishes that I’m very happy with. The various kits have performed perfectly and I’m now surprised more people don’t DIY there own plating. Of course cost may put some people off but once a couple of vital components have been lost by a plater you see the value of being in control of your own parts. I’m frankly amazed that with a bit of common sense and some time I can achieve these results but you get what you pay for. The shot of my YCS1 carbs shows just what can be achieved. The manuals supplied by Caswell are first class, their support via phone or e-mail is excellent and the results speak for themselves. I’ve decided to plate as many components as possible with my ongoing projects and have acquired a mains power supply to allow me more flexibility. It’ll be put to good use when I finally get to grips with the 1962 Yamaha step-through and 24,000 mile, barn find, Stinger! My thanks to “Jeep” of Caswell Europe for his unstinting help, support, encouragement and never ending patience in the compilation of this article.