info on electroplating

How difficult is it to learn to electroplate? I suppose difficult is the wrong word - rather, how much practise will it take to prduce a good quality item? From that question, you can see that I know NOTHING about the subject, but am not too old too learn. I want to plate very small filigree brass castings used in jewelrymaking. Am I on the right track, or is there another process I should look at?

Reply to
Minki
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For small parts, Caswell's "Plug 'n Plate" kits work very well:

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Reply to
David Courtney

Very easy to learn, very hard to learn to do it well. The chemistry is also noxious and hard to obtain - some of it's extremely toxic. You usually need to either buy an expensive kit, or buy in vast industrial-sized quantities.

The acid copper-plating process is simple and easy to obtain the ingredients for (copper sulphate and sulphuric acid) It's certainly the best place to start learning techniques. It doesn't work especially well on steel though, as the acid attacks the steel. OK for practice, not so good for a finished item.

Nickel plating is another easy process to learn with, but you'll have to buy the chemistry from someone like Caswell. It works very well in conjunction with acid copper as a way to make steel items non-rusting. There's also an even simpler electroless nickel process (just chemistry, no electricity - dunk it in a bucket and leave it a while). This is an excellent finish for "model engineering" parts, small tools etc.

Other processes, such as cyanide electrolytes, chrome plating or precious metal plating are outside the scope of almost all home plating and certainly not something to attempt until you've had some experience with the simpler processes.

Good books are the small EMAP / Argus book (any model engineering supplier) "Electroplating" by J Poyner.

This book is quick and simple to read and gives a good grounding as far as it goes. It also covers electroforming. However it completely ignores the old cyanide processes, which are worth knowing about (although rather impractical to use). There's an older edition of a similar book, "Electro-Plating for the Amateur" by L. Warburton (Model & Allied Publications, ISBN 0853440565) which is fairly common on eBay and does cover them.

Also worth tracking down is a commercial plating handbook by "Canning", who supplied the UK plating industries for years. Their recipes are all in the form "Add 4 lbs of Canning Plate-o-matic Powder to a gallon of water" and don't tell you what the chemistry is, but you can learn a lot on techniques from it (especially about anodes).

Couple of old postings of mine, and similr web searching is probably useful

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Most popular supplier of kits is Caswell
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Reply to
Andy Dingley

It is quite easy to do well if you are able to follow simple instructions.

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Caswell's stuff is not cheap, but everything I've tried from Caswell has worked beautifully and his instruction book is excellent. Except for chrome, the chemistry is no more toxic or hazardous than a lot of household stuff and he provides instructions and additional chemicals for safe, ecologically-responsible disposal.

You need not buy the whole kit for each process; just get the chemicals and anodes. You can get everything else at Wal-Mart.

The keys are:

  1. Follow the damned instructions!
  2. Included in the instructions is the repeated admonition that things must be absolutely clean. That's the hardest part to get right. If the work is not absolutely clean, the plating will be lousy.

Use of a DC power supply with variable voltage or variable current is a great help, because there is a "right" current (mA per square inch) for each process. You need not pay big bux for a supply; if you are able to build simple electronic circuitry you can build an excellent current regulator for a few bux that you can use with a battery charger or 12-volt battery. I'd be glad to supply a schematic. A current regulator is nice for two reasons: current is the relevant parameter in plating and anodizing, and it won't blow the fuse in your ammeter when(not if) you inadvertently short things out while hooking up. A $3.95 digital multimeter is quite sufficient.

Based on recent experience, I would strongly recommend eventually having an ultrasonic cleaner as part of your plating kit. I've done a lot of plating without one but it is MUCH easier to get stuff clean with one.

Reply to
Don Foreman

Alkaline copper plates very well directly on to steel, and it accepts nickel well. Zinc also plates steel well, about as easy to do as painting and considerably more resistant to abrasion and metal-to-metal contact. I either zinc-plate or blacken about every small object I make out of steel in the shop, except that I sometimes nickel-plate things like knobs that will be handled a lot.

Electroless nickel is "easy" in that it requires no electricity or anode, but slow because it takes a while to heat up the stuff to working temperature. Also, the electrolyte is depleted with use so it must be maintained and eventually replaced. My electrolytic nickle juice is going on 5 years now and still works fine. I can be done plating something electrolytically in the time it takes the electroless to reach working temp. However, it is very good at getting into holes and even to the roots of internal threads. It will plate anywhere the solution can get.

Reply to
Don Foreman

What do you mean by "alkaline copper" here? Presumably not a cyanide process, for DIY?

Reply to
Andy Dingley

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Not cyanide, but I have no idea what the chemistry might be. I just use the stuff. Works fine on steel. I have also occasionally had trouble getting brass to "start" in electroless nickel, but a flash of copper solves that problem.

Reply to
Don Foreman

Don, Andy, THANKS!

What I forgot to mention, is that although the items I want to do are small, I need todo a LOT of them. I know I'm going to have to buy some commercial equipment, but I want to first play and practice. As my mother always said, before you start yet another project you know nothing about, read and ask questions. So, that is the stage I'm at. Can u use a basket or plate in the botom of a bath that you charge instead of having to string all these small items on a wire to dip? Does that question REALY show my ignorance? Do you tumble the items afterwards to get a smooth finish? Also, buying kits r not easy for me, cause I live in the back of beyond in South Africa, and have to find importers as hazmats can't be shipped overseas. Oh how I envy you your craft shops and Walmarts! Thanks for the info guys, and I will now take my time to get the recommended reading material. Any other pointers will be greatly appreciated

Reply to
Minki

Commercial plating has a lot to recommend it (in the UK anyway) as it's a foul process, corrodes everything around it, and the disposal of wastes afterwards is a pain. It's still pretty lo-tech though. If you _can_ farm it out to a commercial plater, it's often a good plan to do so.

For lots of items then you'll probably want a "basket plater". This is an especially common process for nickel, either electrolytic or electroless. The parts are tumbled in a slowly rotating basket immersed in the plating solution. The basket is part of the circuit and the intermittent contact is sufficient.

Not necessarily. _Equipment_ can usually be improvised, it's the chemistry that has to be bought as ready-made kits. A good controllable PSU with current limiting is worth having, as electronics is sophisticated these days and easy control makes life easier. Cheap digital instruments like weighing scales, thermometers and pH meters make things easier too. As to the tanks, then some basic engineering and improvisation around rubber buckets or roofing lead can achieve a lot.

This is where a Canning's handbook is useful, just to see how the real kit works and then to copy it at home.

No. The tanks develop a sludge layer at the bottom and you want to stay well clear of this. It's also characteristic of plating solutions that old solutions work better than new. They have to be continually refreshed as you use them, but an old solution is well known to "stabilise" in service and often isn't considered ready for commercial use until a couple of days dummy plating, or even well-behaved until it's in use for a month. Certainly try to set up a plating rig and leave it in service undisturbed.

You might, depending on the shape, but most are wheel polished by hand. It's common to plate a thick layer of something soft and polishable to hide defects ansd scratches, then return to another plating bath to put on a different metal for show. Copper chrome is an example of this.

Tumbling in sawdust (tapered octagonal wooden barrels) is often used to dry parts after washing.

AFAIK (from practical experience of South Africans) it's easier to obtain the necessary chemistry in South Africa than in the UK -- even cyanide solutions for case hardening.

Whereabouts are you BTW? I'm off to Durban in July for a wedding.

I bought the last plating rig from a farmer's supply shop. Copper sulphate treats fungal diseases in sheep's hooves. Conc 96% sulphuric acid is commercial drain cleaner. Copper electrodes are scrap plumbing. Calf feeding buckets are conveniently smaller (less solution) and stronger rubber than domestic buckets. Milking parlour fittings are stainless steel and can supply parts for suspension bars. My S hooks for hanging things came from a shopfitter's display rack.

And Walmart is the spawn of evil anyway!

Reply to
Andy Dingley

The last comment first - anywhere that does not stock Festool or thinks a Dremel is something that you might find in the laundry section to me is the spawn of evil! Now, if hardware shops will only open a food section ......

Howcome everyone in SA gets married in Durban? Even I did. I am in the Limpopo province, about 4hrs drive north of Jhb, which makes getting hold of stuff that little bit more difficult - hence wanting to electroplate my own stuff, and once the quality is there, do it commercially. At the moment, I import this stuff, cast in brass, and have it plated in the states before it comes in, but I will get a lot of tax breaks if I bring it in raw and process it myself Now, this basket plater sounds like what I'm looking for, as the items I want to do are TINY - the little bead caps and fancy ends used in jewelry - go look at your wife's stuff. I thought of buying a kit or two to play with and get a better feel for what I'm letting myself in for, but shipping hazmats are prohibitively expensive, and exhaustive searching on the net have not produced a supplier in SA yet.

Any idea who makes a basket plater? And do you have an opinion as to which would be better - a magnetic finisher, a vibratory tumbler or a rotary tumbler? Items r too small for spindle polishing. And then I suppose before i start anything, it has to go in a pickle for cleaning?

Thanks again for putting up with all my questions

Reply to
Minki

With my cynical hat on, probably no-one does. The last one was made in the '50s and since then plating (in the West at least) has been in terminal decline. There's so much around on the scrap market that no-one makes new stuff any more. W. Canning Materials Ltd of Birmingham, UK made all of it in the first place and they're still in business at least. On the other hadn, if Harbor Freight can start importing an English Wheel, anything is possible.

You really do need to get hold of a copy of the "Canning Handbook on Electroplating" though -- it's _the_ book on doing plating commercially. No doubt the jewellery trade have something similar for their small-scale preciousses. Oppi Untracht's huge and worthwhile book probably covers plating too (although I don't have it to hand).

No idea, as it's out of my size range for my limited experience.

Cleaning is important, but there's a whole range of these cleaners and pickles. Some are so powerful that exposure is timed to the second, others are themselves electrolytic.

To be honest, I think you might need to have this stuff done commercially if it's for jewellery. You have to be careful to avoid _any_ nickel (legally careful, with preserved records and everything) and the plating baths for precious metals have high set-up costs.

Reply to
Andy Dingley

You want to accomplish your polishing before final plating. Objects are sometimes copper plated and then polished because copper is easy to polish and takes a mirror finish. Then they must be cleaned (again) before final plating. An ultrasonic cleaner might be excellent for the small objects you describe. I've found that work that is bright before plating is bright after plating. Decorative plating is typically quite thin (microns)so it won't permit much polishing.

I don't think chemistry for nickel plating is hazmat.

It might be useful to explore things a bit with Caswell, at least to get started. They say they do supply to small commercial operations. I don't know if they ship to Africa or have an affiliate there.

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They might be willing to anwer a lot of your questions. I think their clientele is comprised mostly of hobby platers like myself, and small commercial platers like auto restorers, gunsmiths, jewellers, etc.

Good luck!

Reply to
Don Foreman

replying to Minki, J wrote: Its an old post so I am only posting in case others tread this path - after all I came in from Google.

Firstly the OP did not state what metal he wants to plate onto brass.

You can get way with acid copper plating process on brass - it is true that the acid will attack the zinc in the brass but reasonable plating can be done in this case assuming that your copper acid bath contains the appropriate additives ( levellers and so on ).

In general plating is not a great idea for the amateur its usually cheaper and less disapointing if you go to a professional.

The level of cleaning to produce a good long lasting finish is beyond the amateur in most cases - a plating that looks good today may peel blister or display stains at a much later time otherwise - if you intend to sell how are you going to know you will not get returns in a year's time. Commercial outfits use things like vaour solvent cleaning ( heat up really nasty solvents so that they turn to gas in a sealed chamber and effectively "steam clean" only the "steam" is not water but some really nasty solvent that would do you significant damage if you inhaled ).

Plated surfaces require protection fron tarnishing in most cases and spray on lacquer from your DIY supplier is not going to give reliable protection for commercial application ( again if you are selling products ) particularly if it is to be worn, getting the right kind of protection for use and the choice of metal really is a specialist field in itself.

FInally many plating processses ( for different metals ) involve really nasty chemicals - copper sulphate is not too bad although toxic to marine life but from there on it tends to get nasty - nickel salts are not great for the environment and if you are plating in any kind of commercial situation ( you are selling your products) you could quickly get fined if you do not deal with disposal, guard against container failuire ( see bunding ) you could be fined by the authorities - water treatment plants monitor spikes in heavy metals and will quickly follow up any releases that they detect, commercial platers tend to dread this as they then have to undertake a chemical audit.

Many amateurs get very shirty or irritated when told all of this - they feel its the nanny state or others are dumping on their freedom to experiment but just ask yourself what is the chance of someone buying a plating kit actually disposing of the chemicals responsibly - what is the chance they even understand the chemistry well enough to know how to safely handle the chemicals.

Really when you factor in the quality of the plating - its longevity, quality and the expense you will spend getting it right it really is better to go to a professional and focus on other areas of your work that you can do yourself.

Reply to
J

Reply to
Novo Precision

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