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Electrolytic rust removal question
I've been reading through web pages and old posts about electrolytic rust removal, and apparently using stainless as an electrode is a no-no due to toxic waste concerns. As such, a "graphite rod" is the preferred thing. My question is, when they say "graphite rod" do they mean any specific type of graphite rod? Could I use rods for carbon arc welding, or graphite rods used for EDM? Looks like Enco has graphite EDM rods on sale (or at least they did a little while ago) and I've been wanting to try removing some rust with this technique, but I'm not sure if these are the rods I should/can be using or not. Thanks in advance for any assistance! |
Electrolytic rust removal question
Don't know where you read that but my electrode is a piece of rebar from Home Depot. Works great. Steve. "The Hurdy Gurdy Man" wrote in message ... I've been reading through web pages and old posts about electrolytic rust removal, and apparently using stainless as an electrode is a no-no due to toxic waste concerns. As such, a "graphite rod" is the preferred thing. My question is, when they say "graphite rod" do they mean any specific type of graphite rod? Could I use rods for carbon arc welding, or graphite rods used for EDM? Looks like Enco has graphite EDM rods on sale (or at least they did a little while ago) and I've been wanting to try removing some rust with this technique, but I'm not sure if these are the rods I should/can be using or not. Thanks in advance for any assistance! |
Electrolytic rust removal question
On Sat, 14 Feb 2004 10:37:20 GMT, The Hurdy Gurdy Man
wrote: I've been reading through web pages and old posts about electrolytic rust removal, and apparently using stainless as an electrode is a no-no due to toxic waste concerns. As such, a "graphite rod" is the preferred thing. My question is, when they say "graphite rod" do they mean any specific type of graphite rod? Could I use rods for carbon arc welding, or graphite rods used for EDM? Looks like Enco has graphite EDM rods on sale (or at least they did a little while ago) and I've been wanting to try removing some rust with this technique, but I'm not sure if these are the rods I should/can be using or not. Thanks in advance for any assistance! Just find the cheapest source of graphite that you can. I found some on eBay. Whatever you use, remember this: a bit flat piece has much more surface area than a rod. More surface area = more current. I got lucky and found some big graphite blocks that I bandsaw into 1/2" thick plates. (Move your saw outdoors for this. It's a messy job. Don't set the saw on your driveway, either.) There's a problem with searching for "graphite" on eBay. You'll get thousands of listings of tennis racquets to golf clubs to fishing poles. Instead, search for graphite plate*, graphite stock, graphite bar*, etc. The * is a wild card that will give you hits on both plate and plates. The binder in some types of graphite doesn't hold up well in the electrolysis vat. I've had some graphite plates dissolve in a day or so. On the other hand, I've had some graphite last for a year, or more, under continuous use. If you have a foundry or mill that uses an electric arc furnace or an aluminum smelter, nearby, see if you can beg some stub end of their carbon rods. Here's a tip: If you have a 3,000 psi pressure washer, use it for removing the gunk that forms during electrolysis. It works great and saves lots of elbow grease. Good luck. Orrin |
Electrolytic rust removal question
"The Hurdy Gurdy Man" wrote in message
... I've been reading through web pages and old posts about electrolytic rust removal, and apparently using stainless as an electrode is a no-no due to toxic waste concerns. As such, a "graphite rod" is the preferred thing. My question is, when they say "graphite rod" do they mean any specific type of graphite rod? Could I use rods for carbon arc welding, or graphite rods used for EDM? Looks like Enco has graphite EDM rods on sale (or at least they did a little while ago) and I've been wanting to try removing some rust with this technique, but I'm not sure if these are the rods I should/can be using or not. Thanks in advance for any assistance! First, I'm curious about what the toxic waste issue would be with stainless. Do you have a link or a reference? For swabbing, I use a 1.25" x .75" x 9" slab of Poco 3 (EDM graphite) that I cut off an old EDM electrode with a hand saw. It cuts about like maple. EDM graphite has no binders and Poco 3 is very dense and strong. It probably will outlast me and the next two generations of my family. I just clamp the battery clamp from my 4A battery charger to the end of it and wear rubber gloves. For use in a tank, my electrode is a plain sheet of mild steel (the cover off an old microwave oven) that I sanded clean on one side with a disk sander. Just wipe it dry when you're done. I see no need for stainless. However, I do wonder about what could be toxic in using stainless for this job. Ed Huntress |
Electrolytic rust removal question
Ed Huntress wrote:
For use in a tank, my electrode is a plain sheet of mild steel (the cover off an old microwave oven) that I sanded clean on one side with a disk sander. Just wipe it dry when you're done. I see no need for stainless. However, I do wonder about what could be toxic in using stainless for this job. Could be chromium. Also, you are talking about the *anode*. This is the sacraficial electrode in plating so you will be eroding a metalic anode into your solution thus conaminating it. You won't get the eroded material plating out nicely - concentrations are all wrong for plating. Graphite won't do that so is to be preffered for electrocleaning. Ted |
Electrolytic rust removal question
"Ted Edwards" wrote in message
... Ed Huntress wrote: For use in a tank, my electrode is a plain sheet of mild steel (the cover off an old microwave oven) that I sanded clean on one side with a disk sander. Just wipe it dry when you're done. I see no need for stainless. However, I do wonder about what could be toxic in using stainless for this job. Could be chromium. Also, you are talking about the *anode*. This is the sacraficial electrode in plating so you will be eroding a metalic anode into your solution thus conaminating it. You won't get the eroded material plating out nicely - concentrations are all wrong for plating. Graphite won't do that so is to be preffered for electrocleaning. From my reading about the process (and I know little about electrochemistry myself), it appears there is no erosion of metal involved at all, on either side. That's why I question the idea that stainless causes a problem. Ed Huntress |
Electrolytic rust removal question
On Sat, 14 Feb 2004 20:44:15 GMT, "Ed Huntress"
wrote: From my reading about the process (and I know little about electrochemistry myself), it appears there is no erosion of metal involved at all, on either side. That's why I question the idea that stainless causes a problem. Ed Huntress I have used stainless because I have some sheet which is about the right size. I have neither seen or measured any loss from the stainless anode although it is very obvious (from current variations) that one must run with reverse polarity regularly to de-polarize the anode. I imagine that carbon would not suffer from this problem??? Mark Rand RTFM |
Electrolytic rust removal question
Do a google search on electrolysis, and you'll find quite a bit of info.
Here's one particular article written by a friend of mine - Richard Angelico of New Orleans, La. He is a fellow relic-hunter who finds quite a bit of good 'ole Civil War ordinance - specifically - he finds a good many bombs and cannonballs. He uses 316 stainless for his anode... and his results are fantastic. Link to his article: http://www.troycustomdetectors.com/s...ctrolysis.html Rex S. Mark Rand wrote in : On Sat, 14 Feb 2004 20:44:15 GMT, "Ed Huntress" wrote: From my reading about the process (and I know little about electrochemistry myself), it appears there is no erosion of metal involved at all, on either side. That's why I question the idea that stainless causes a problem. Ed Huntress I have used stainless because I have some sheet which is about the right size. I have neither seen or measured any loss from the stainless anode although it is very obvious (from current variations) that one must run with reverse polarity regularly to de-polarize the anode. I imagine that carbon would not suffer from this problem??? Mark Rand RTFM |
Electrolytic rust removal question
"ShadowHawk" wrote in message
news:vyyXb.37236$jk2.81553@attbi_s53... Do a google search on electrolysis, and you'll find quite a bit of info. Here's one particular article written by a friend of mine - Richard Angelico of New Orleans, La. He is a fellow relic-hunter who finds quite a bit of good 'ole Civil War ordinance - specifically - he finds a good many bombs and cannonballs. Some may be interested to know that they use this method to reduce rust and to remove salt from metal objects recovered from ancient ship wrecks. The time they leave it in the tank is often up to two YEARS. Yike. Ed Huntress |
Electrolytic rust removal question
"Mark Rand" wrote in message
... On Sat, 14 Feb 2004 20:44:15 GMT, "Ed Huntress" wrote: From my reading about the process (and I know little about electrochemistry myself), it appears there is no erosion of metal involved at all, on either side. That's why I question the idea that stainless causes a problem. Ed Huntress I have used stainless because I have some sheet which is about the right size. I have neither seen or measured any loss from the stainless anode although it is very obvious (from current variations) that one must run with reverse polarity regularly to de-polarize the anode. I imagine that carbon would not suffer from this problem??? I don't know, Mark. The people who seem to know what they're talking about on this subject describe it as a very weak action, which won't even affect black rust (Fe3O4). It only works on red rust. The weak alkaline solution doesn't produce any significant quantity of ionized metal ions. It doesn't do much of anything, in fact, except strip red rust somehow. The black grunge that remains on the part is mostly black rust. It comes off easily with a light brushing from a stainless brush. In a couple of cases I've used hydrochloric acid to remove the black rust, and then put the part back in the electrolytic process in the hope that it will remove any chloride ions picked up from the acid. I don't know. But I have a lot of de-rusted parts to show that it does a good job. Ed Huntress |
Electrolytic rust removal question
In article , Ed Huntress
says... Some may be interested to know that they use this method to reduce rust and to remove salt from metal objects recovered from ancient ship wrecks. The time they leave it in the tank is often up to two YEARS. Yike. That's *nothing* Ed. I personally have some rusty artifacts in my shop that have remained in situ for up to *five* whole years. They seem to be aging quite nicely indeed. :^) Jim ================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ================================================== |
Electrolytic rust removal question
On Sat, 14 Feb 2004 15:55:08 GMT, "Ed Huntress"
wrote: First, I'm curious about what the toxic waste issue would be with stainless. Do you have a link or a reference? Snip Ed Huntress I don't have a reference, but I have about eight years of almost continuous experience using electrolysis. I was told that stainless steel wouldn't degrade when used as a waste electrode when doing electrolytic derusting. So, I used a thin sheet of SS scrap. It took a while, but the sheet stainless eventually looked like a lace curtain. Worse, my solution turned yellow: hexavalent chromium. I once worked at a facility where they pumped their discarded chromate-treated cooling tower water into the ground. That was then. Now, hundreds of millions of yours and my tax dollars are being spent trying to get it pumped back out of the aquifer. Orrin |
Electrolytic rust removal question
"Orrin Iseminger" wrote in message
... On Sat, 14 Feb 2004 15:55:08 GMT, "Ed Huntress" wrote: First, I'm curious about what the toxic waste issue would be with stainless. Do you have a link or a reference? Snip Ed Huntress I don't have a reference, but I have about eight years of almost continuous experience using electrolysis. I was told that stainless steel wouldn't degrade when used as a waste electrode when doing electrolytic derusting. So, I used a thin sheet of SS scrap. It took a while, but the sheet stainless eventually looked like a lace curtain. Worse, my solution turned yellow: hexavalent chromium. That's interesting. Did you use one of the standard, weak alkaline solutions? Ed Huntress |
Electrolytic rust removal question
On Sun, 15 Feb 2004 17:29:42 GMT, "Ed Huntress"
wrote: ,;"Orrin Iseminger" wrote in message ... ,; On Sat, 14 Feb 2004 15:55:08 GMT, "Ed Huntress" ,; wrote: ,; ,; ,; First, I'm curious about what the toxic waste issue would be with ,;stainless. ,; Do you have a link or a reference? ,; ,; Snip ,; ,; Ed Huntress ,; ,; I don't have a reference, but I have about eight years of almost ,; continuous experience using electrolysis. ,; ,; I was told that stainless steel wouldn't degrade when used as a waste ,; electrode when doing electrolytic derusting. So, I used a thin sheet ,; of SS scrap. ,; ,; It took a while, but the sheet stainless eventually looked like a lace ,; curtain. Worse, my solution turned yellow: hexavalent chromium. ,; ,;That's interesting. Did you use one of the standard, weak alkaline ,;solutions? Ed If you throw the kind of voltages that are used in this process at an anode something is going to give. You can't pass a current from an electrode into a solution without a chemical reaction. At the anode it is either an oxidation of something in solution or an oxidation of the anode. You must have one or the other to pass a current. If the current is so high that there is nothing available from the solution to oxidize then the anode is going to go. ,; ,;Ed Huntress ,; |
Electrolytic rust removal question
"Don Wilkins" wrote in message
... On Sun, 15 Feb 2004 17:29:42 GMT, "Ed Huntress" wrote: ,;"Orrin Iseminger" wrote in message ... ,; On Sat, 14 Feb 2004 15:55:08 GMT, "Ed Huntress" ,; wrote: ,; ,; ,; First, I'm curious about what the toxic waste issue would be with ,;stainless. ,; Do you have a link or a reference? ,; ,; Snip ,; ,; Ed Huntress ,; ,; I don't have a reference, but I have about eight years of almost ,; continuous experience using electrolysis. ,; ,; I was told that stainless steel wouldn't degrade when used as a waste ,; electrode when doing electrolytic derusting. So, I used a thin sheet ,; of SS scrap. ,; ,; It took a while, but the sheet stainless eventually looked like a lace ,; curtain. Worse, my solution turned yellow: hexavalent chromium. ,; ,;That's interesting. Did you use one of the standard, weak alkaline ,;solutions? Ed If you throw the kind of voltages that are used in this process at an anode something is going to give. You can't pass a current from an electrode into a solution without a chemical reaction. At the anode it is either an oxidation of something in solution or an oxidation of the anode. You must have one or the other to pass a current. If the current is so high that there is nothing available from the solution to oxidize then the anode is going to go. Ok, I'm just listening, but it strikes me funny, because I've seen no evidence that my graphite- or mild-steel electrodes have eroded. I do have a good triple-beam balance. Maybe I'll start weighing that sheet of mild steel, before and after. I certainly do enough of it that I should be able to measure it. Ed Huntress |
Electrolytic rust removal question
On Sun, 15 Feb 2004 17:29:42 GMT, "Ed Huntress"
wrote: Snip That's interesting. Did you use one of the standard, weak alkaline solutions? Ed Huntress I use washing soda with a little lye thrown in to cut any grease or paint that might be on the item. Orrin |
Electrolytic rust removal question
On Mon, 16 Feb 2004 06:19:24 GMT, "Carl Ijames"
wrote: I completely agree that you have to have oxidation at the anode, I just find it hard to belive that you will produce Cr(VI) and not Cr(III). So far as I remember my electrochemistry courses, electrolytic dissolution pretty much always produces the lowest stable oxidation state. I've done a lot of electropolishing of stainless steel, and those solutions always turn green, consistent with Cr(III). Have you chemically verified the presence of hexavalent chromium or did you just trust the color, which could be due to dissolved rust or other metal ions at low concentration (no, I didn't on my solutions)? No, I haven't run any chemical analysis. I'm not in a position where I have to prove anything to myself. In eight years I've used a variety of electrodes and have seen just about every color in the solution caused by the rust being removed. The only time I got a yellow solution is when I used stainless steel that disinegrated as described. I've been around lots of stationary Diesels that used chromate-treated coolant. The appearance was exactly the same. That's good enough for me. I have never seen a green-tinted electrolyte in my setup. If I tell people to use stainless electrodes and they go ahead and do. And, if they discard their electrolyte on their property, what position does that put me into? In this litigious society, I'm going to express every caution that I can think of. Orrin |
Electrolytic rust removal question
On Mon, 16 Feb 2004 06:19:24 GMT, "Carl Ijames"
wrote: ,; ,; It took a while, but the sheet stainless eventually looked like a ,;lace ,; ,; curtain. Worse, my solution turned yellow: hexavalent chromium. ,; ,; ,; ,;That's interesting. Did you use one of the standard, weak alkaline ,; ,;solutions? ,; ,; If you throw the kind of voltages that are used in this process at an ,; anode something is going to give. You can't pass a current from an ,; electrode into a solution without a chemical reaction. At the anode it ,; is either an oxidation of something in solution or an oxidation of the ,; anode. You must have one or the other to pass a current. If the ,; current is so high that there is nothing available from the solution ,; to oxidize then the anode is going to go. ,; ,;I completely agree that you have to have oxidation at the anode, I just ,;find it hard to belive that you will produce Cr(VI) and not Cr(III). So ,;far as I remember my electrochemistry courses, electrolytic dissolution ,;pretty much always produces the lowest stable oxidation state. I've ,;done a lot of electropolishing of stainless steel, and those solutions ,;always turn green, consistent with Cr(III). Have you chemically ,;verified the presence of hexavalent chromium or did you just trust the ,;color, which could be due to dissolved rust or other metal ions at low ,;concentration (no, I didn't on my solutions)? I agree that Cr+6 is not going to be produced. I never said that Cr+6 was produced. I doubt if it happens and if it was produced it would be reduced to Cr+3 at the cathode. There is no way one will accumulate chromates in this procedure. For those who don't believe that the anode can be dissolved note that this fellow has been doing electropolishing. For the uninitiated the piece to be electropolished is the anode. They ramp the voltage up so one gets anodic dissolution in addition to the normal gas evolution. The theory is that the peaks dissolve faster than the valleys so one ends up with a flat surface. In fact the theory is correct and with the proper voltage and proper solutions you can make some pretty nice stainless steel mirrors. In order to make those mirrors one dissolves stainless steel from the surface. I rest my case. One of those solutions was a mixture of acetic anhydride and perchloric acid. That one is not for the faint of heart. Due to some faulty decisions an entire city block was removed in Los Angles. That gave some more bad publicity to the perchloric acid business. My research director owned the largest plant for producing perchloric acid in the USA at the time. He was not pleased. |
Electrolytic rust removal question
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Electrolytic rust removal question
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Electrolytic rust removal question
Orrin Iseminger wrote:
On Sun, 15 Feb 2004 17:29:42 GMT, "Ed Huntress" wrote: That's interesting. Did you use one of the standard, weak alkaline solutions? I use washing soda with a little lye thrown in to cut any grease or paint that might be on the item. Of the various solutions I've tried for electrocleaning, I've had the best success with this one: http://www.metalworking.com/dropbox/_1999_retired_files/E-CLEAN.TXT Ted |
Electrolytic rust removal question
"Ted Edwards" wrote in message
... Orrin Iseminger wrote: On Sun, 15 Feb 2004 17:29:42 GMT, "Ed Huntress" wrote: That's interesting. Did you use one of the standard, weak alkaline solutions? I use washing soda with a little lye thrown in to cut any grease or paint that might be on the item. Of the various solutions I've tried for electrocleaning, I've had the best success with this one: http://www.metalworking.com/dropbox/_1999_retired_files/E-CLEAN.TXT Yes, it's your formula that I use, Ted, and it works great. I have no idea why some of those ingredients are in there, but it works. g In a tank, I just use washing soda. Ed Huntress |
Electrolytic rust removal question
On Mon, 16 Feb 2004 18:56:30 GMT, Ted Edwards
wrote: Of the various solutions I've tried for electrocleaning, I've had the best success with this one: http://www.metalworking.com/dropbox/_1999_retired_files/E-CLEAN.TXT Ted Your recipe is the one I tell folks about, but perhaps you can shed some light on it for me. When I do the calculations for a 55 gallon batch (I have two vats, one 55-gallons and the other over 100-gallons) that figures out to a very large quantity of washing soda. Out of necessity, I mix my solutions weaker. I still get all the current draw that my power supplies can handle. Orrin |
Electrolytic rust removal question
Orrin Iseminger wrote:
Your recipe is the one I tell folks about, but perhaps you can shed some light on it for me. What's the question? When I do the calculations for a 55 gallon batch (I have two vats, one 55-gallons and the other over 100-gallons) that figures out to a very large quantity of washing soda. Out of necessity, I mix my solutions weaker. I still get all the current draw that my power supplies can handle. Your weaker solution will have lower conductivity but, from your last sentence, that is irrelevent to the current flow. Do you find it just as effective as a higher concentration? Ted |
Electrolytic rust removal question
On Tue, 17 Feb 2004 18:55:01 GMT, Ted Edwards
wrote: Orrin Iseminger wrote: Your recipe is the one I tell folks about, but perhaps you can shed some light on it for me. What's the question? Other than current draw, is there any advantage to mixing my solutions as strong as your recipe calls for? Because of the size of the parts I de-rust and the size of my "waste" electrodes, I'm able to load all my DC power supplies to their rated capacity, 10 amperes. When I do the calculations for a 55 gallon batch (I have two vats, one 55-gallons and the other over 100-gallons) that figures out to a very large quantity of washing soda. Out of necessity, I mix my solutions weaker. I still get all the current draw that my power supplies can handle. Your weaker solution will have lower conductivity but, from your last sentence, that is irrelevent to the current flow. Do you find it just as effective as a higher concentration? Ted I've only mixed a five gallon batch according to your recipe. I've never been able to see any difference between the results it brings and the results my weaker solutions yield in the large tanks. Orrin .. |
Electrolytic rust removal question
"Orrin Iseminger" wrote in message
... I've only mixed a five gallon batch according to your recipe. I've never been able to see any difference between the results it brings and the results my weaker solutions yield in the large tanks. Orrin Regarding tanks, have you ever compared the weak solution of Ted's formula with the performance of straight washing soda? Ed Huntress |
Electrolytic rust removal question
Orrin Iseminger wrote:
I've only mixed a five gallon batch according to your recipe. I've never been able to see any difference between the results it brings and the results my weaker solutions yield in the large tanks. The big difference between us is that I was doing occassional cleaning and plating and was concerned about deterioration of solutions sitting around in tanks. I, therefore, pursued brush cleaning and plating and never really tried a more dilute solution in a tank. I would guess that the more dilute solution *might* take longer to work. This would be a PITA for brush work. I would say that if you don't see any difference in performance, dillute it even further until you do. I would appreciate hearing the results. Ted |
Electrolytic rust removal question
On Wed, 18 Feb 2004 14:39:13 GMT, "Ed Huntress"
wrote: "Orrin Iseminger" wrote in message .. . I've only mixed a five gallon batch according to your recipe. I've never been able to see any difference between the results it brings and the results my weaker solutions yield in the large tanks. Orrin Regarding tanks, have you ever compared the weak solution of Ted's formula with the performance of straight washing soda? Ed Huntress I tend to use clothes washing powder, with a bit of bicarbonate of soda if I have it lying around. Seems to work ok for me. I suspect that anything ionic, basic and with non strongly-oxidising ions will do the job. Mark Rand RTFM |
Electrolytic rust removal question
On Sun, 22 Feb 2004 00:45:48 +0000, Mark Rand
wrote: I tend to use clothes washing powder, with a bit of bicarbonate of soda if I have it lying around. Seems to work ok for me. I suspect that anything ionic, basic and with non strongly-oxidising ions will do the job. Mark Rand RTFM I was asked to give a demonstration, once, and couldn't find any washing soda. So, I used Arm and Hammer Fabricare, instead. It worked, but the suds were a nuisance. Orrin |
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