Obviously electroplating requires some specialist chemicals as well as a variety of pieces of equipment, some of which are essential and others optional. The easiest way to get started is to go for one of the plating kits which are available online from a number of sources. I picked up my plating kit from www.classic-plating.co.uk. This was what they call the ‘professional plating kit‘ which simply means it’s a little larger and slightly more comprehensive, including among other things, a tank heater, an air bubbler and a tank filter. Whilst in theory it would be possible to plate parts with just this kit alone, I think it would be difficult to get anything like decent results so in my opinion you should look to buy some extra equipment as I shall explain…
\Below are the contents of the kit I purchased…
· Plating chemicals (enough to make 15 litres of electrolyte)
· Starter and brightener chemicals
· Zinc anodes
· Alkaline degreaser
· Pre-plating acid pickle
· Air pump, air stone and tubing
· Tank filter
· Tank heater
· 3 x 10 litre tanks
· Yellow/Gold passivate (makes up to 9 litres)
· Blue/Clear passivate (makes up to 9 litres)
· Connection kit comprising; red & black wire, stainless steel wire, copper wire and crocodile clips
· Safety equipment comprising; gloves, safety goggles and dust mask
· Variable current controller for use with 12v supply (car battery etc)
· User guide
Right away I realised that the three tanks (in this case white 10 litre plastic buckets with lids) supplied in the plating kit was not going to be enough. You are supposed to rinse the items between each stage of the process so clearly you are going to need more than three tanks. The basic process would be as follows… 1) Degrease, 2) Rinse, 3) Acid dip, 4) Rinse, 5) Plating, 6) Rinse, 7) Passivate, 8) Final rinse. So as you can see, three tanks isn’t even enough for the components of the plating process let alone the rinsing as well! Fortunately, these white plastic buckets are readily available and not too expensive. I bought ten more complete with lids via eBay for £27 including delivery.
You might also want to consider buying some shallow plastic trays like I did as it will help to contain drips and minor spills. I bought these locally for £1 each. They are big enough to place two tanks on each one. They are also handy for sorting small fasteners and help prevent them from falling off the table.
The kit did contain the necessary chemicals for the plating process (I’ll cover exactly what they are in the next part) and for preparing parts, however I think when you are starting with the kind of rusty, oily parts you are likely to have from a restoration project, it is asking a lot of the two chemicals provided (alkaline degreaser and acid pickle) to get them cleaned back to perfect bare metal… and even if you could, the two tanks would become contaminated and dirty very quickly. So, I elected to create a pre-treatment process of my own and for that I turned to Bilt Hamber and their excellent range of products. For degreasing, their Surfex HD is hard to beat and for removing rust Deox-C does the job better than anything else I have tried. These two products are easier and cheaper to replace once fully used up and with them you can get parts virtually ready to plate before even going into the alkaline cleaner. If you can get the parts to be plated cleaned to a high standard before you get to the alkaline degreaser process, then that and the acid pickle just become the final prep prior to plating without them having to do any heavy cleaning.
Of course this will require another four tanks, two for the chemicals and two for rinsing, bringing us to a total of twelve tanks… but wait… also, as you have two kinds of passivate available to use (yellow and blue), you will also need an extra tank for one of those so ultimately you will want a total of thirteen tanks, which brings me neatly to my next subject…
You are going to need quite a bit of space for this whole operation. I had a spare room I could use and three folding tables measuring 1525mm x 760mm (5′ x 2’6″)… and I needed all of that space! It’s helpful if you can layout the tanks in the process order with enough space where needed for sorting parts and wiring them ready for plating etc. It’s also wise to label the tanks clearly. I used an old Dymo embossing label maker for this. Also, you will need to make sure you have enough space to hang plated parts up to dry, store your de-ionised water and any used chemicals or waste and, if needed, supply some heating to the room if it has none. The plating process does not work well in a cold environment!
One thing you do not get in your kit but one which is vital is water, or more accurately de-ionised water. For all of your electroplating, pre-treatment, passivation and rinse tanks, you will need pure de-ionised water of the sort used to top up lead-acid batteries. You can buy this from any decent motor factor or accessory shop but you will need to buy it in large quatities so make sure they can supply it in 25 litre drums. You are going to need at least 90 litres just to get started! The Deox-C and Surfex HD tanks don’t really require it but once you are past that pre-treatment process, I think it’s wise to use de-ionised water to prevent contamination of the plating tanks. For the plating and passivation (and rinses) it is absolutely essential. I managed to get the cost down to £11 for a 25 litre drum locally so budget another £40-£50 for water. Also bear in mind that your rinse tanks will become contaminated over time so will need refreshing from time to time with clean de-ionised water. Contaminated rinse water can still be used to top of the relevant process tank when needed (top up the plating tank with the plating tank rinse, the acid pickle tank with the acid rinse and so on). With this in mind it’s a good idea to try to negotiate a big bulk discount from your supplier. The empty water drums can be used to store used chemicals too but be sure to label them clearly so you know what is stored in them!
The kit provides a fish-tank type heater for using with the electroplating tank. The plating process needs to be heated but I found that it’s highly beneficial to heat the passivate as well. I had some issues initially with the passivate coming off but heating the passivate tank seems to remedy it. This also means that the post-plating rinse and final rinse will also need to be heated otherwise you will be taking the metal components from hot to cold to hot again. Fortunately, fish-tank heaters can be bought for about £5 each online. You will only need to heat around 10 litres with each one so they don’t need to be big heaters. Also, as your tanks are not deep, be sure to buy the shortest heaters you can find as you do not want them sticking up out of the liquid or they may overheat and fail.
As I alluded to earlier, it also helps to make sure that the space you are working in is warm. I use a small oil filled electric radiator for this. It’s also good for helping to dry finished parts.
One more thing that benefits from heating is Deox-C. If you use a fish-tank heater to heat the Deox-C tank you will find it strips rust very quickly… in fact many times faster than if it is cold. DO NOT leave the heater on when not in use though as I found it makes the Deox-C crystallize to the sides of the tank! The same goes for the other tanks… turn the heaters off when not in use and fit the lids to prevent evaporation.
The Plating Tank
Now we come to the heart of the process, the plating tank itself. The instructions in the kit suggested simply twisting together the zinc anode plates together with copper wire and dangling them over the side of the tank. This didn’t sound like a very good idea so I drilled the tank to fit M6 stainless steel bolts which were secured with plain washers and nyloc nuts though the sides of the tank and connected together with wires around the outside. The plates were drilled to fit onto the ends of the bolts and secured with M6 wing-nuts. This makes them quick and simple to remove and refit as well as making sure they stay securely in place. This is useful as you must remove the plates from the electrolyte when it’s not in use or they will dissolve, contaminating the the electrolyte in the process.
The fish-tank heater comes with sucker mounts but I found that they didn’t stay attached to the side of the tank for long so I recommend smearing them with some silicon sealer before sticking them in place. Likewise, the air stone and tubing supplied to provide agitation in the tank tends to float due to being full of air when in operation so it benefits from being stuck down to the bottom of the tank with silicon sealer too. A filter was also supplied but I found it to be useless so in the end I didn’t use it. Some kind of filtration would be good but as yet I haven’t looked at alternative methods. Sticking the heater mounts down with silicon applies to the other heated tanks too but be sure to let it dry properly before filling the tanks.
The kit comes with a rather rudimentary power controller designed for use primarily with a car battery. I did have a brief go with this and found it quite unsatisfactory. It also gets extremely hot which doesn’t seem particularly safe! Fortunately, I found a variable 12 volt DC power supply at a car boot sale for £5 which seems to do the job. This power supply is only just man enough for the job as it run consistently with it’s cooling fan going and it’s ‘overload’ light illuminated but as yet it hasn’t cut-out or failed. These kind of power supplies are plentiful on eBay so I would recommend getting one. They have the advantage of giving you greater control over the plating current. You can also monitor the plating current using the multi-meter provided in the kit.
Of course, you can use the controller provided and a car battery or possibly even a battery charger but however you choose to do it, you need to be able to control the power as it really effects the plating quality and the time it takes to plate items.
Something else not catered for by the kit at all is the need to support parts to be plated in the tanks. The instructions for the kit suggests using a bar to suspend parts from on wires but I found the best way was to wire the parts together using copper or stainless steel wire then hang them from some small wire mesh squares. These are actually little racks for cooling freshly baked cakes on! I bought them locally for about £1 each. These happen to be exactly the right size for sitting on top of the 10 litre tanks and allow you to suspend several sets of parts evenly spaced out in the tank. In this way I can plate about eighty fasteners or more at a time or you can suspend one or two large objects from them instead. It’s best to have a few of these on hand as you will find you have parts in various parts of the process at the same time as well as plated parts drying on them. I’d suggest having at least four to six of these.
So finally we come to the bit that most people don’t read… Safety. This process involves some dangerous chemicals, heat and electricity so it has plenty of potential for causing personal harm, so be aware of this and prepare for it. The kit provides some gloves, goggles and a mask, none of which are much use in my opinion. The gloves are decent enough and chemical proof but I found the are no long enough to allow you to put your hand into the tank to retrieve a dropped part from the bottom. I bought a pair of full length (above the elbow… see pic) chemical gloves which make things safer. I also have disposable nitrile chemical resistant gloves which I wear all the time whilst using this process. I even wear a pair under the full length gloves for some extra protection. It’s worth paying a little extra to get good quality acid resistant ones rather than the thin sort you get from motor factors.
You definitely need to protect your eyes from splashes so goggles are essential but I would go one futher and buy yourself a full face shield to wear as well. I just used the one I keep in my workshop for use when grinding. With this you can’t even get a splash on your face. Remember, you are dealing with some VERY caustic chemicals which you DO NOT want on your skin under any circumstances!
The dust mask is not very useful in my opinion. It’s okay for preventing inhilation of dust when mixing up the solutions but after that you are dealing with vapour instead. This process does create some fumes although not a lot, but none of them will be stopped by a paper dust mask. Keep the area well ventilated and if you want, get a mask that will deal with the kind of vapours you may encounter. It’s best to seek advice on this one as I cannot make any suggestions. Workspace ventilation is important though so it’s advisable to make sure that you can have a window open when plating.
I would also advise wearing a water or chemical proof apron of some sort so you are safe against spills onto your clothing. Keep plenty of paper towel and cloths handy to clean up spills and dry your gloves on and make sure you have a waste bin to put stuff in.
Be methodical in everything and not only will you get better plating results but you are also much less likely to have any accidents. Do-it-yourself plating is a pretty satisfying endeavour but it is also not without risk, albeit small. Know the risks and work safely. The user guide supplied with the plating kit contains more safety information as well as data sheets for the chemicals involved.
One extra which whilst not essential is very useful is an ultrasonic cleaner. Having previously owned a tiny ultrasonic cleaner of the type used for cleaning jewelry, I thought it would be a good thing for cleaning parts for plating too so I bought a larger three litre capacity unit from eBay for just under £100. This is very helpful for cleaning parts and speeds the process up somewhat over just soaking parts. Although this represents a significant investment if purchased just for plating, it fortunately has plenty of other workshop uses. One of the best is cleaning carburettors, in which it excels, as it has the ability to loosen deposits blocking the small drillings in a carb body. It is a handy thing for cleaning any intricate or delicate part that is hard to do by hand. All I use in it is water with a little detergent like washing up liquid or similar. You soon realise how effective it is when you see how quickly the water gets dirty!
Second extra worth having is some timers. Some of the processes need to be timed fairly accurately, especially passivation which effects the final colour of the parts. It’s wise to have some kind of device to time things by. A stop watch or even your mobile phone could be used but far better it to buy some small digital kitchen timers. These are very cheap and can be pre-set with a time measured in seconds or minutes. Getting one for each timed process and pre-setting it to the required time makes things much simpler as you don’t need to keep adjusting the pre-set… just press start and it’ll count down and sound and alarm when done. Reset and it’s ready to go again.
The level of rinse tank contamination can be monitored by measuring the pH level of the water. This can be achieved with some litmus papers which are available very cheaply on eBay. Obviously, rinse water should be pH neutral but if it starts to become acidic or alkali then it’s time to change it. Likewise, you can monitor the pH level of other solutions to see if they remain constant. It’s helpful to have an infra-red laser thermometer for checking the temperature of the heated tanks too.
So, in summary you can see that whilst a plating kit is an essential purchase, it really only provides half of the equipment needed for DIY plating. Clearly the extras add to the cost significantly so this should be a consideration when deciding if you want to have a go at this yourself. To recap, the extras you would need to set things up the way I have include the following…
· 10 x 10 litre buckets
· 10 x plastic trays
· 90 litres of de-ionised water
· M6 Stainless bolts, nyloc nuts and washers
· Some extra copper or stainless steel wire
· 4 x metal cake cooling racks
· Bilt Hamber Deox-C
· Bilt Hamber Surfex HD
· Adjustable Power Supply
· 5 x fish-tank heaters
· 3 x Digital timers*
· Ultrasomic cleaner*
· Infrared laser thermometer*
· Litmus papers*
· Long, chemical resistant gloves
· Safety face shield
In the next part, I’ll go though the set-up and the process itself step-by-step and highlight some of the potential problems which you might come up against.