About home nickel plating (to recover wear)

graham-xrf

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First - this is about nickel electroplating with current. Electro-less nickel deposition is a separate thing.

There is a huge available store of knowledge about nickel plating. One only has to trawl the patents.
The usual plating baths use nickel chloride and nickel sulfate with "additives" for all sorts of purposes. Brighteners, buffer solutions, deposition rate regulators, whatever, but the basic transport is the nickel salts. They will be called "proprietary". We send our stuff out to be nickel plated.

So now I see videos on YouTube about "Easy DIY Nickel Plating" using vinegar and salt. You first make the electrolyte to an effective concentration from vinegar and nickel electrodes, using any small wall-wart ex-phone charger, or bench supply. The voltage needs to be low to keep the current below one or two amps. The conductivity is greatly improved by adding some salt. If you use a small battery charger - then less salt. Once you get the green solution, you can just keep using it until you contaminate it.

Actual plating is to put the cleaned steel on the cathode, and clip the positive to the nickel strip, and it starts accepting metal.

I wonder - has anyone in HM tried this and got a plating that adhered well?

Here is the first video I saw. There are many others, some with refinements about pre-treating, cleaning, etc.


I admit that I have messed about some with anodizing using battery acid, but this trick is different.
 
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when i was a youngster in grade school, my teacher had the class electroplate pennies and nickles with vinegar, water, and table salt.
we used 1.5v d cell batteries
first we nickle plated a penny, then we copper plated a nickle.
the process was not refined in any way, but i was impressed how well it worked for only plating for short periods of time
i can't imagine a very thick deposit layer in the method i was shown, but longer (or repeated) soaks should produce thicker plating
 
when i was a youngster in grade school, my teacher had the class electroplate pennies and nickles with vinegar, water, and table salt.
As is the way with me, I usually have a deeper plan. Nickel is about the same hardness as steel.
It also happens to be corrosion resistant, but that is a bonus. I can see a clear wear track on the underside of the lathe tailstock. I can also see the original machining marks on the unworn regions. The insides of the 45° vee that goes over the prism slideways would have taken similar wear.
Suppose..
First, an electrolytic "derusting" in something alkaline (sodium carbonate) AKA washing soda, using carbon electrode, which is self-limiting. It does not chew the metal, nor leave it prone to fresh rust spawning the instant the high area micro-structure sees air. It takes care of all the pores. This applies only to unpainted, unmasked areas. I would use a wax or paint or other resist.

Then, a nickel plating, thick enough to take up the wear, around 0.0015" to 0.002". This plating would also build up the surfaces in the worn vee. The thickness of the plating can be very finely calculated from current x time x the weight of the ions deposited, but easy enough to simply measure at intervals.

Then cut back. Lap it on a flat. Draw filing even, but remove nickel until the machining marks are again seen on the non-worn regions. Alternatively, bring out the 1/10ths micrometer, or in my case, the 0.001mm, and keep checking the lapping cutback.

What happens in the vee is measured by using a ground dowel laid in in it. If the relationship to the unworn surfaces is known, and it is, then using a dowel the correct size to fit the inscribed circle to fit the vees allows the whole thing to be set on a surface plate for measurement. We should be able to rub back, or otherwise correct the plating in the vee, but it is bound to already be close to the correction for the flat. It should not need much adjustment, if any.

A dreamed up plan, maybe just crazy, but I am finding it hard to say it will not work. If the plating can be put on, in a controlled manner, and it will adhere well, I am thinking it may be a way to restore a worn thing back to like new!
 
A word of caution regarding the use of electroplating + back-lapping as described in post #3. Electroplating will fill in the scratches as well as the high spots, so all the surface features will "telegraph" up through the plating. Lapping will then remove the high spots, so the scratches will not appear -- they will disappear.

I know this because of my experience in a type of integrated circuit processing called CMP. It is used to produce metal lines that are co-planar with the insulator around them. It is done by etching grooves in the insulator, putting down a thin "strike" layer of metal and electroplating copper over the whole thing. This fills-in the grooves as well as the high spots. Then the high areas are polished away, leaving the metal in the grooves. This is how IC manufacturers make metal lines that are 14 nano-meters wide.

Regarding scratches in a metal substrate, If the deposited metal is a different color (say, copper or gold) they WILL show up after lapping due to the color contrast but the surface actually will be scratch-free -- other than the ones you make during the lapping process itself.
 
A word of caution regarding the use of electroplating + back-lapping as described in post #3. Electroplating will fill in the scratches as well as the high spots, so all the surface features will "telegraph" up through the plating. Lapping will then remove the high spots, so the scratches will not appear -- they will disappear.

I know this because of my experience in a type of integrated circuit processing called CMP. It is used to produce metal lines that are co-planar with the insulator around them. It is done by etching grooves in the insulator, putting down a thin "strike" layer of metal and electroplating copper over the whole thing. This fills-in the grooves as well as the high spots. Then the high areas are polished away, leaving the metal in the grooves. This is how IC manufacturers make metal lines that are 14 nano-meters wide.

Regarding scratches in a metal substrate, If the deposited metal is a different color (say, copper or gold) they WILL show up after lapping due to the color contrast but the surface actually will be scratch-free -- other than the ones you make during the lapping process itself.
My thanks to you @homebrewed. Clearly an expert! I suppose what I am contemplating is just a bigger, (and somewhat rougher) version of chemical metal planarization.

I still have to do more homework on electroplating, but I love the idea of leaving a visible metal "tracer" on the original surface machining surface and in the marks, to signal the cutback has gone far enough. I am, of course, just experimenting with it at my leisure. Unless one is in a determined hurry, there is not much to lose here. If it "goes wrong", it can be fixed. I have taken the precaution of measuring at multiple points, from the opposite side surface.

The picture is of the tailstock base underside worn and unworn regions measured from the "semi reference topside". The condition is "washed a bit", but still unclean. To come is paint strip + electrolytic de-rust + whatever else I can think of. The scratches and pits will be clean, but I take care not to etch away metal.
Tailstock Base Measure2a.png
The silly variance is because the top "semi-reference" is not extremely "flat". It did not need to be. I have since taken off the high spots, but left the original machining marks.

The nickel anodes have been purchased from eBay, and this is definitely going to be tried out. I confess that here there is a growing store of little boxes, bags and tubs of basically "fun with chemistry stuff - grown up version" + a cheap, (though not the rock bottom Chinese pits), pH meter.

The "homework" is a bit more involved than the casual finding of a bit of YouTube knowledge. There are 31 patents about nickel electroplating I thought useful, and 14 on electro-less nickel deposition from solution I found interesting. Then some on copper, silver, chrome, and gold (don't ask)!

Nickel is the almost default material to get the "first strike", for many other metals that might follow.
I will definitely play with the vinegar, but I think there has to be a reason modern plating shops use nickel salts instead.
Thanks again for the cool idea! :)
 
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Yes. I followed a similar YouTube video and plated several bolts on a drill press I redid. This is the only pic I have on my phone I wanted to keep them from rusting again 64D44C04-D899-40F3-B8BE-F1B7E0B1871D.jpeg
 
I hadn't thought of using a contrasting metal as a kind of "end point" indicator -- thanks for the idea!
 
Yes. I followed a similar YouTube video and plated several bolts on a drill press I redid.
@Rootpass: You have great pictures, and I am convinced. I also hate rust. Somehow I feel that if we spent all that fossil energy tearing the stuff from it's ore, we should not so easily allow nature to claim it back. That is a waste!
The bolts on my kit are going to be treated.

Just in passing - it is the vinegar + salt method you used, is it not?
and..
If you had any experiences or comments about what you did to follow the YouTube videos, do tell.

Nice bolt heads!
 
I hadn't thought of using a contrasting metal as a kind of "end point" indicator -- thanks for the idea!
Eh? You may have been thinking in terms of the other context (CMP) at the time, and not quite realized it, but the idea is entirely yours, actually set out in full in the last paragraph of post #4.

I read it in terms of what I wanted - a tracer to let me know I had reached the un-worn surfaces, yet leaving a load of nickel buildup in the "wear trough".

I would draw the line at ending up with every pit, scratch and other blemish from pre-nickel recovery being proudly displayed as "inlaid in gold"! There should be tasteful limits to MPBS (Machine Poser Bling Syndrome)!

But.. it is not such a crazy idea, because you can lay down less than 500 to 1000 atoms thickness with a small wipe of cotton wool soaked in gold plating solution. This would highlight the pits and cracks and a bottle good for a much as ever you need for this job is $20 to $35 (a tiny bottle). If you use a small voltage, and be holding the swab in forceps, it goes on in about a minute. Enough gold to actually fill the scratches to the top is out of order OTT!
BTW - don't touch the toxic stuff!

I think copper will do just as well. We want to fill the whole pit or scratch.
 
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