Electroplating

[Matt]

This is a pretty different idea I've been thinking of, let me know what you think.

You could make a boiler out of aluminum foil, put it in some plastic container. Fill the inside of the boiler with copper (II) sulphate solution, and the area outside with water so as not to stress the delicate aluminum. Connect the aluminum to the negative terminal of a power supply. Suspend copper connected to the positive terminal of the power supply in the centre of the boiler, and plate copper onto the inside. Then you sand off the aluminum on the outside.

Copper (II) sulphate is sold in pet stores in solid or solution for use as an aquarium algacide.

[Aidas]

I know nothing about these things, though it sounds interesting.

Instead of sanding off the aluminum, why not plate the outside after you've plated the inside?

Aidas

[stoker]

that sounds crazy. I think you'll never get a solid boiler, the layer will never be thick enough nor smooth

[possum]

I rather agree with stoker.

[hornedrhodent]

that sounds crazy. I think you'll never get a solid boiler, the layer will never be thick enough nor smooth

Electro-forming is used to make stuff out of copper when it is very difficult to make using conventional methods. I have some rectangular curves where the internal cross section of the tube is critical. (microwave guides) These were electro-formed and are about 2mm thick.

In terms of a boiler I'd plate the outside of the aluminium if you want a smooth inside surface. The surface you plate on to determines the finish. The other surface does tend to be rougher depending on current density and electrolyte movement. Sharp corners and edges tend to plate more heavily than uniform surfaces. The aluminium could be dissolved later with acid - I'd avoid caustic soda with copper.

That being said - it takes a lot of electricity - I've misplaced my little science data book so I'm guessing here - 1 mole of copper is 32 gm and takes 2 mole of electrons to produce from Cu++. I think I worked out (years ago) that one mole of electrons is about 11 Ah. That would be a lot of car batteries worth to make the kilograms of boiler you'd need.

It would be possible to do it but much easier to solder one up out of copper sheet.

[Matt]

Less than one volt is required. Current densities around 100A/m2 are well below the point at which surface roughness will occur. According to my calculations, using very conservative numbers for efficiency, 100A/m2 would yield a deposition rate of 2.2 mm /weak. An old spot welder transformer could be used, and most welding shops will have rectifiers of required capacity.

This is how all electrical grade copper is refined. Copper used for plumbing is not refined in this way. Electrorefining removes nasties like lead, mercury, arsenic, and zinc.

If all it takes is time... well if you're fermenting and distilling your own spirits you clearly have enough time for a little do-it-yourselfing.

[mtnwalker2]

Interesting concept.

What would happen if one submerged a SS keg into a plastic container of the copper sulphate?

[Husker]

Interesting concept.

What would happen if one submerged a SS keg into a plastic container of the copper sulphate?

I would think it better to try to coat the inside with copper, and possibly the bottom of the keg (better heat conductivity of copper).

Interesting idea, however, if it would actually "work".

H.

[Matt]

Interesting concept.

What would happen if one submerged a SS keg into a plastic container of the copper sulphate?

You would plate the outside with copper, which will give you the look. If you want to reduce sulphurous nasties you would need to plate the inside.

You can plate anything you want really, as long as is conducts electricity.

If some areas are getting overplated you can move the source copper around, or mask the areas with beeswax.

[mtnwalker2]

I was actually thinking both, inside and out. I think it would make for a really neat look and help with cleaner distillation some.

[Husker]

Take a heck of a big plating vat to do a 15.5g keg in though. A lot more than I would have access to.

However, I wonder if you could fill the keg, and simply plate the inside of it?

H.

[msrorysdad]

I'd like to do the inside of my keg. If one of you brain trusts think of and use a method, I'd like to see it so I can copy.

[mtnwalker2]

I'm sure that would work. I was thinking though of a cheap plastic garbage can. Just happen to have one. But it probably would need 2 independent processes anyhow. Meybe a silver plate on the outside?
It would be a one of a kind. Meybe, I'll have to check out my wifes jewelry.

[Husker]

I think the only 2 reasons to plate the outside, are:

1. better thermal transfer (only meaningful on the bottom, or bottom 1/3 if doing double boiler).

2. better looking.

Since I dont give a crap about the look of my still, and only worry about the final product, a pretty still is not something I care about. If this was a commercial operation (which I may do, since the laws here in NE are may be changing to allow micro distilleries within eating establishments), then looks "might" matter. However, being that this is in the garage, or back shed, who gives a flip what it looks like. I and my friends like the end results, so that is what I strive for.

However, plating the inside of a keg would be a nice (novel) thing. It might help a little. However, it would have to be pretty smooth, so that the boiler could be cleaned up well. But it would be nice to have a "100%" copper contact still.

H.

[mtnwalker2]

Thanks Husker,

Actually useing lead or plastic would be safer than using what very little jewelry I was ever able to give her. I think though ( the inside copper treatment would be worth a try.) Nothing ventured, nothing ....! I will try it on my quarter keg to see.

Pintoshine has been working on plans for a large SS pot still, and I was thinking of makeing a simular one with copper cut offs, and end runs of copper roofing, 22" wide by however long, at scrap metal prices and with a jug or 2 for incentive. However, this sounds much cheaper, and easier. Still, I would like an all copper 50 gal pot still, like he is makeing. An extra jug or 2 at the end of a job, might not cost me anything.

Heck, on a rainy day, and since they are much more experianced than I am, I could submit the plans, supply the solder and flux, and walk out with a very quality boiler. They also use a heavy gauge 3" downspout that would make an awsome column.