So my question is based around using ball bearings inside extractors as a conductor for removing energy from the center of a column or inside a “chiller” stack. Carbon steel is a much better conductor than stainless but I think adding iron oxide in any amount will start to mess with pH in weird ways. So the easy answer is chrome plating, but I could only find minimal info (one study) about chrome shaving being used to remediate waste water from tanneries. Also, I’m an idiot who could have completely misunderstood the nerdy and academic language used therein.
Not food safe
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Well now I feel dumb for not looking at it from that angle to begin with, lol. Is the same true for carbon steel? Or is there another plating metal, like rhodium, that is food safe? 
I’m asking this but also going back to Google immediately. Now that you helped me get my keywords on point. FML, lol.
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Answers a big old nope for plating carbon steel with pretty much anything, but carbon steel itself is food safe. So I’m thinking I’ll have to live with lower conductivity which means I’ll have to use more ball bearing to achieve the same cooling effect.
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Look for 304 or 316 stainless
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Sanitary steel is much better & not as porous material, much cleaner extract & doesn’t degrade due to weaker structure.
Copper is conductive.
and food safe.
All the research I found indicated copper was only considered food safe if coated. They use it on the bottom of lots of stainless cookware for sure, but even the classic copper cup traditionally used in serving moscow mules comes lined with stainless. And raw copper oxidizes in really weird ways. I actually took a whole college course on metal patinas and metallic finishes as it would apply to historical restoration of buildings, so we didn’t really cover any chemistry:sob:
, but I learned bunches about putting chemicals on copper to turn it blue.
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Also, there’s a bunch of papers available from the petroleum industry about hydrocarbons and stainless interactions but they are brain meltingly boring and mostly to do with crazy chemicals in petroleum distillation.
And copper is way more conductive than carbon steel and way way way more than stainless. It’s the benchmark actually, at 100, only thing more conductive is silver if I remember intro to DC circuitry at all. Silver >copper> gold> aluminum though I may have gold and aluminum mixed up.
Nickel actually is a lot better conductor than both.
One of the only metals that heats & cools within that same time frame of its thermal transfer.
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By sanitary do you mean stainless? Stainless is virtually nonporous, clearly everything is mostly empty space at the quantum level, but otherwise it’s considered nonporous as a physical material.
I’m just trying to clarify, for myself, what you are saying, as I believe I’m misunderstanding your point.
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I say sanitary as in 316 stainless steel, not just typical stainless. It has a much better hold up & won’t corrode from hydrocarbons overtime & other acidic compounds that are within extraction or some conversions in most cases. Also a reason that I would never use copper on any setup as it would be subject to corrosion much faster than any other material currently used on market by trusted manufacturers for equipment.
Thanks for clarifying, yeah I totally agree with all that, especially the copper bit.
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300 or 400 series stainless will both work fine from a corrosion standpoint.
Stainless steel ball bearings would more likely be a 400 series stainless than a 300 series, which is too soft to use as a bearing. They would have a K value of about 19, with carbon steel around twice that.
Silver would be perfect around K-400 or gold at about K-300 but for the price, so consider compromising with Nickle shot like they use in investment casting foundries, with a K-90.
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https://images.app.goo.gl/p9Gk3nb5e6tZptXw8
Still no idea how to take a screenshot on my phone after 2 years owning it
Great link, nothing comes close to silver and copper, I love lists.
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Did a quick cost analysis stainless to silver. A 7mm sterling silver bead is 73 cents. Maybe my calculations are wrong but I believe it would take 1300 beads to fill one vertical inch of a 6 inch tube… So basically a grand. Not impossible but stainless is like 1/100 the cost.
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Exactly
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