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Evan
11-27-2009, 10:53 PM
I did some experiments this afternoon electropolishing stainless steel. It turns out that it is stupid simple to get a reasonable result. I took information from some patents and deciphered the very clever ploy of using the chemical formulae for dish soap and antifreeze and discovered the ingredients of the bath.

1 part by volume of 80% phosphoric acid
1 part by volume of propylene glycol (auto antifreeze)
1 part water
1/4 part ethanol or isopropanol
5 grams liquid dish soap per litre of water

Use a stainless steel container as the cathode (negative electrode)

Line the container with one or two layers of plastic window screen to prevent short circuits.

This bath does not contain acids that are likely to pose a problem to health. Phosphoric acid is non toxic and is not a particularly dangerous chemical. You do not want to get it in your eyes so wear appropriate eye protection. It does not cause a high intensity exothermic reaction if water is added to it but it is still a good idea follow the rule of adding acid to water, not water to acid.

For these initial tests I used 2 12 volt batteries to supply the power.

I don't have a lot of pictures of the actual treatment in progress because the process does release some fumes. The fumes are very benign, smelling very mild and mostly like dish washing soap. I ran the test in my garage shop as fumes of phosphoric acid will not cause rust. Phosphoric acid is used for rust conversion on iron. But, I didn't trust having the camera in the vicinity of the fumes for long.

My test was cut short because I accidentally shorted a piece to the pan causing a pinhole leak. Hence my suggestion to line the pan with some plastic window screen.

The process draws a lot of current, anywhere from 25 to 150 amps per square foot. Car batteries are the best bet. I will be doing some more experiments and I am going to try using just 12 volts to see what happens. The solution needs to be hot but I discovered that all you need to heat it is to process a part and the current flow will quickly heat up the solution.

Correct temperature is 150 to 220 F. Nothing seems to very critical about this so feel free to change the formula for the bath or use a different power supply. The part is always positive.

Here is the setup:

http://ixian.ca/pics6/epolish.jpg

Some results:None of these were in the bath more than a few minutes. I had a time limit because of company staying here returning from a funeral.

The results are obvious even after just 30 seconds.

The last of these images is aluminum and it seems that this bath may work just as well with aluminum as SS. It certainly cleans it in a hurry.


http://ixian.ca/pics6/epolish2.jpg

http://ixian.ca/pics6/epolish3.jpg

http://ixian.ca/pics6/epolish4.jpg

Walter
11-27-2009, 11:11 PM
Thanks Evan!

This is particularly interesting to me as we work with alot of stainless and this may well prove to be something we can make use of. We already have a dedicated setup for de-rusting and could easily convert to do this in. At the very least it's something I'm gonna have to play with.

doctor demo
11-28-2009, 12:48 AM
Just seeing if I can bump the counter up to 43.

Steve

Evan
11-28-2009, 11:44 PM
I am really surprised so few people seem interested in this. I recall quite a few comments on this subject in the past.

Anyway, I did some more testing to day.

Number one. I think it would be a good idea to greatly reduce the dish soap content, perhaps to less than a gram per litre. It produces a lot of very tough and very dense fine foam that poses a problem overflowing the container.

2: You do not need a heater. The main problem is keeping the solution cool, not hot. When the part is first dunked it will pull very heavy current unless some sort of current limiting is used. I think a panel or board with a set of headlights might be a good idea.

Another way to reduce the current draw at the expense of longer treatment times is to reduce the acid percentage in favour of more water.

I ran a part today that was a pretty good test. It's a brushed stainless steel electrical faceplate. I was curious if the process would be able to remove the fine scratches of the brushed finish. It can and leaves a nice finish of it's own. It isn't mirror bright but it is a very fine satin almost a mirror finish.

I intentionally left out one ingredient from the bath formula and that may be required to achieve a true mirror finish. That is 1/2 part of sulphuric acid which I didn't want to use inside the shop. This time of year it is too cold to do these experiments outside so I went with a shop safe formula. Even so this is a very acceptable process for producing an even and good looking finish on stainless steel.

http://ixian.ca/pics6/epolish7.jpg

http://ixian.ca/pics6/epolish6.jpg

dp
11-28-2009, 11:49 PM
Just so you know, I'm very interested and have dropped your post into my local folder. I just didn't have anything to add - the original post was complete, shovel ready, etc.

kmccubbin
11-29-2009, 01:11 AM
Add me to the interested list! I've been waiting impatiently for the update.

Kerry

Evan
11-29-2009, 01:27 AM
I will be running some more experiments with this. I want to see what effect is has on other alloys of steel. I also want to do some more tests on aluminum. I will keep it updated as I have results to report.

barts
11-29-2009, 01:38 AM
Great post Evan - thanks!

Keep in mind that most antifreeze in the States is ethylene glycol rather than propylene glycol. The former is toxic to felines and attractive to them as well, so kitties beware! The latter is generally marketed as "green" antifreeze.

- Bart

macona
11-29-2009, 02:10 AM
Interesting. I have a little electropolishing setup from Tektronix and it does have a heater to heat the solution. There are probably a lot of different recipes out there. Everything I have heard is the stuff is pretty nasty.

whitis
11-29-2009, 02:12 AM
Keep it up, this is interesting.

You mentioned some patents but didn't give patent numbers or whether they are expired and whether your version would be covered.

Increasing the water may be a bad way to reduce the current (better done with current regulation or lower voltage) as it may lead to pitting instead of polishing.

One thorny issue is solution maintenance/disposal. Ideally, you want to be able to measure the solution so you can maintain the concentrations, use your successive rinse water baths to replace evaporation for each previos stage (i.e. shooting for zero waste water emissions), precipitate out the metal and separate the components or render them harmless when the solution gets old. Unfortunately, all the metal probably does not plate out on the cathode. But it seems you have a safer solution to use than most.

Here is a non-expired patent using salt and antifreeze:
http://www.patentstorm.us/patents/6835300/description.html

Here is a listing of a large number of electropplishing recipes.
http://www.fischione.com/product_support/model_110_application_notes.asp

Caswell plating's take on why they don't offer electropolishing kits:
http://forum.caswellplating.com/metal-polishing-questions/1221-anyone-here-do-electro-polishing.html

Hydrogen gas produced can lead to an explosion hazard. Usually it blows away but if you are polishing the inside of a tank...
http://www.hse.gov.uk/foi/internalops/fod/oc/600-699/655-6.htm
Perchlorite solutions are even worse.

motorcyclemac
11-29-2009, 02:52 AM
Ooooh... I think you may have just shown how to save me a LOT of time with stainless steel revolvers. I might just have to try this out. It would clean and polish all the hard to get parts.

Evan...have you measured the material? Does it change it dimensionally?

Cheers
Mac.

Evan
11-29-2009, 03:03 AM
I have no intention of patenting anything. Patents are a goldmine of information though. In the case of the patents I found on this subject the writer tried to obscure the chemicals used by referring to them by the least often used chemical name for the product. As example the propylene glycol was referred to as a propylene oxide derived polyol. The dish soap was called out as a fatty acid ester from lauryl sulphate.

I have used propylene glycol because it is non toxic and is not regulated so far as disposal is concerned. Neither is phosphoric acid and both ingredients are available in food grade quality. The only issue at all is the small amount of dissolved metals from the levelling process. Most of that should be plated out of solution on the cathode. The primary dissolved metal will be iron and that is also not regulated as many water supplies contain significant amounts of iron. That leaves very small amounts of nickel and chromium. Only the chromium is of interest and then only if it is present in hexavalent form.

The reactions should produce trivalent chromium which is an essential trace element for plants and humans. The solution can be poured out on the ground without harm.

Propylene Glycol antifreeze is readily available at any RV dealer for use in protecting the potable water supply lines.

Mac,

It will change dimensionally but I highly doubt that it is enough to worry about. I wouldn't expect to see a change of more than a couple of tenths at the most.

SDL
11-29-2009, 04:26 AM
It will change dimensionally but I highly doubt that it is enough to worry about. I wouldn't expect to see a change of more than a couple of tenths at the most.

We use electro polishing a lot on stainless at work via subcontract polishers like these http://www.anopol.co.uk/electropolishing.htm to produce these UV Systems http://www.hanovia.com/products/pmt.aspx.

The process is capable of halving the surface finish but when doing complex pipe shapes electrodes are required to get to the inside surfaces.

Threads can be a problem as they can reduce in size dramatically if small compared to the main mass, i.e. an M5 stud on a big tank.

If doing welded fabrications they are normally pickled in a acid tank overnight before going into the e.pol tanks

Steve Larner

Evan
11-29-2009, 06:23 AM
Yes, threads should be protected. The process depends on the fact that the pointy bits are eroded faster than the flat areas. The large initial current is due to the many microscopic burrs and edges that are present from previous machining operations.

Protecting threads is easy as they can be wrapped with electrical tape for OD threads or plugged with a plastic threaded plug for ID threads. Since the process is a form of electroplating the action is mostly line of sight to the cathode and the closer it is the faster the reduction in high points. As long as the suface area to be treated is visible it will be acted on by the process.

In the case of a firearm virtually no erosion will take place in the ID of the barrel or cylinder of a revolver. Some rounding of OD corner detail is likely and engraving could be obliterated. Serial numbers should be masked.

whitis
11-29-2009, 06:59 AM
I have no intention of patenting anything. Patents are a goldmine of information though.

The question wasn't whether you were going to patent it but rather whether someone else already has and whether the patent still holds. Patents can be a wealth of information ... that you can't use. Anyone here who uses the process in any commercial capacity needs to be concerned about the patents. And unfortunately, the stuff that is likely to be still covered by patents is the newer stuff that meets modern environmental standards.

Propylene glycol MSDS: "Whatever cannot be saved for recovery or recycling should be managed in an appropriate and approved waste disposal facility. Processing, use or contamination of this product may change the waste management options. State and local disposal regulations may differ from federal disposal regulations. Dispose of container and unused contents in accordance with federal, state and local requirements. "
Of course, the MSDS for water might say the same thing. It also says:
"When released into the soil, this material is expected to readily biodegrade. When released into the soil, this material is expected to leach into groundwater. When released into water, this material is expected to readily biodegrade. When released into the air, this material is expected to be readily degraded by reaction with photochemically produced hydroxyl radicals. When released into the air, this material is expected to have a half-life between 1 and 10 days. "
http://www.jtbaker.com/msds/englishhtml/p6928.htm
Another MSDS for Propylene Glycol gives instructions to treat a land or water spill like other hazardous wastes:
http://www.google.com/search?&q=propylene%20glycol%20disposal
Yet says it is not a hazardous waste.
This one says that aqueous solutions under 95% are don't have a flash point but that over 22% flamable vapors are produced when heated. And the flash point if over 95% is near the boiling point of water.
http://www.ppe.com/msds/Propylene%20Glycol.pdf
But MSDS tend not to tell you how you can really dispose of stuff.

There has been at least one case of a small airport being prevented from discharging into the sanitary sewer system. In other places, it is allowed:
http://www.cdphe.state.co.us/hm/hhw/howto/antifreeze.htm

Propylene glycol doesn't sound all that bad but disposal is still a little ambiguous even for the pure form, let alone mixtures.

I had the suspicion that glycerin may work and apparently this is the case, though most of the articles are pay to view. Nitric/sulfuric acids and glycerine, though, can make nitroglycerin. May not patented unless you are electopolishing semiconductor wafers aided by ultrasonics or using an acid other than phosphoric: http://www.faqs.org/patents/app/20080213995
http://www.freepatentsonline.com/EP0941373.html
http://www.patentstorm.us/patents/5096550/description.html
http://www.patentstorm.us/patents/7501051/claims.html
The second of these, incidentally, involves polishing carbide cutting tool inserts. The fourth one patents certain rather odd concentrations. Glycerine is a waste product of biodiesel - unfortunately in that case it is often contaminated with methanol. Apparently, adding glycerin to the sanitary sewers can substantially increase methane bio-gas production to the point that at least one treatment plant deliberately adds it. Also is compostable.
http://www.journeytoforever.org/biodiesel_glycerin.html

Phosphoric acid might be useable (after pH correction?) in composting or soil additive as phosphorous is a critical soil nutrient. At least in small quantities that can't leach into waterways (phosphates cause trouble). If some soap is used, a potassium based soap would be preferable to a sodium one but the quantities are very small. Phosphoric acid is also used to separate glycerin in biodiesel so there is some information on phosphoric acid/glycerin combinations:
http://www.journeytoforever.org/biodiesel_glycsep.html
"In the electropolishing of aluminum and for coloring by electrochemical means, glycerin used as an inhibitor prevents excessive etching and helps produce a smooth, white surface."
http://www.sdascience.org/docs/Uses_of_Glycerine.pdf

Thing is even if the ingredients are safe, when you mix acids, organics, and metals and apply electricity, who knows what other compounds you might produce?

There can be some surprise contaminants of alloys. Cobalt-60 can be a contaminant of some stainless steel (particularly from a particular plant in india, and possibly 4 others) or in irradiated metals. Otis elevator had to replace the buttons in 600 elevators. Oak Ridge discusses eliminating from electopolishing solutions:
http://www.osti.gov/bridge/servlets/purl/211395-F8y1hE/webviewable/211395.pdf
Lead is an additive in some free machining steels.

Drain disposal of laboratory Quantity Chemicals to the Sanitary Sewer (1 liter/day max):
http://www.ehs.uconn.edu/Chemical/Lab%20Drain%20Disposal.pdf
"Solutions containing any amounts of Arsenic, Barium, Cadmium, Chromium, Lead, Mercury, Selenium, Silver, Copper, Nickel, Osmium and Zinc should not be discarded into the sanitary sewer system."
An electopolishing solution would probably contain serveral.

Quantity, of course, makes a big difference. What in small quanities could be beneficial in large quantities could be bad news. Soil normally contains a variety of elements, including those metals likely to be found in an electropolishing solution.
http://www.answers.com/topic/soil-chemistry

Anyone who could come under scrutiny by the EPA or other agencies would do well to dot their i's and cross their t's.

But you might have the beginnings of a fairly green process here.

Detail proceedures for an electopolishing solution for stainless steel using glycerin, phosphoric acid, and sulfuric acid:
http://psfcwww2.psfc.mit.edu/esh/epolish.htm
http://www.metalast.com/documents/Technical_Bulletins/Processes/TB-SS.pdf

Electropolishing stainless steel micro-needles with "in a solution containing water, phosphoric acid and glycerin in a ratio of 1:3:6"
http://aiche.confex.com/aiche/2006/techprogram/P59329.HTM

aboard_epsilon
11-29-2009, 08:15 AM
Is this really just for tarnished stainless ..

or does it remove scratches and turn brushed finished stainless to polished finished .

if it does not ..then i would rather just use metal polish ...for a couple of mins .

all the best.marekj

Evan
11-29-2009, 08:49 AM
Propylene glycol doesn't sound all that bad but disposal is still a little ambiguous even for the pure form, let alone mixtures.


Help. You are seriously confusing the issue. Propylene glycol is used to protect potable water plumbing from freezing in situations where the plumbing is not in use such as in a RV or a closed house. How do you think it is removed from the lines? The water is turned on and it is flushed down the drain. I recommend running the water for at least 10 minutes as the stuff tastes terrible.

BTW, are you related to oldtiffie?

Propylene glycol USP from DOW Chemical:



PG USP/EP from Dow is an important ingredient for a multitude of uses, including:

Solvent for aromatics in the flavor-concentrate industry
Wetting agent for natural gums
Ingredient in the compounding of citrus and other emulsified flavors
Solvent in elixirs and pharmaceutical preparations
Solvent and coupling agent in the formulation of sun screen, lotion, shampoos, shaving creams and other similar products
Emulsifier in cosmetic and pharmaceutical creams
Ingredient for low-temperature heat-transfer fluids involving indirect food contact, such as brewing and dairy uses, as well as refrigerated grocery display cases
Very effective humectant, preservative and stabilizer in semi-moist pet food (with the exception of cat food), bakery goods, food flavorings and salad dressings

http://www.dow.com/propyleneglycol/prod/pguspep.htm

Evan
11-29-2009, 08:52 AM
Is this really just for tarnished stainless ..

or does it remove scratches and turn brushed finished stainless to polished finished .


This isn't just a cleaning process. It is a levelling process. It actually makes the finish flat. I will take a comparison micrograph a bit later this am of the surface of the faceplate and post it.

mochinist
11-29-2009, 08:52 AM
BTW, are you related to oldtiffie?lol I was thinking the same thing

aboard_epsilon
11-29-2009, 09:07 AM
This isn't just a cleaning process. It is a levelling process. It actually makes the finish flat. I will take a comparison micrograph a bit later this am of the surface of the faceplate and post it.

i want you to scuff a bit a stainless up with 100 grit paper ..then do the polishing process ..
only then will i be convinced .

where the hell do you get phosphoric acid from cheap ?

all the best.markj

Evan
11-29-2009, 09:14 AM
Phosphoric acid is sold for adjusting the pH of greenhouse water supplies. Check with anybody that supplies the greenhouse trade.

I'll try a test today using a scuffed sample.

John Stevenson
11-29-2009, 09:18 AM
I am really surprised so few people seem interested in this. I recall quite a few comments on this subject in the past.



Evan,
Just because someone doesn't post on it doesn't mean to say they are not interested.
I have read this and found it very interesting, I have no intention of ever using it due to not needing it but nether the less it's still interesting to read how other are tackling different problems.

.

QSIMDO
11-29-2009, 10:07 AM
Phosphoric acid is sold for adjusting the pH of greenhouse water supplies. Check with anybody that supplies the greenhouse trade.


And any farm supply store.
It's used for cleaning milk stone out of milking/storage equipment.

Tony Ennis
11-29-2009, 11:04 AM
Patents can be a wealth of information ... that you can't use.

More accurately, they are a wealth of information... from which you can't derive income.

Market the mixture, you have a problem. Use it in your garage, no problem.

Evan
11-29-2009, 11:37 AM
from which you can't derive income.


You can if it has expired. :D

This one is a good reference. It was granted in 1949.

http://www.freepatentsonline.com/2461035.pdf

J Tiers
11-29-2009, 12:09 PM
More accurately, they are a wealth of information... from which you can't derive income.

Market the mixture, you have a problem. Use it in your garage, no problem.

Not at all true. If you derive a benefit from it, i.e. you use it, you have deprived the patent holder of the income he otherwise could have gotten from you (directly or indirectly). Therefore your private use of the patented process or device is exactly equivalent to selling a product based on it with no license, just on a much smaller scale.

You are unlikely to be prosecuted, but that is at least partly because your use is not known to the patent holder. And also because the results are not likely to pay. But a patent holder has an obligation to take note of, and demand cessation of, any unlicensed usage. If that is not done, the patent may become null and void, and non-action could even be a defense in the case of an infringement, claiming that the patent has been nullified by non-defense of rights.



This isn't just a cleaning process. It is a levelling process. It actually makes the finish flat.

Probably better to say it is a 'smoothing" process to avoid confusion. The chemical action has little effect on overall flatness as was discussed in the 'glass plate thread". What it does is to remove small roughness. There would be little effect on a large radius bow of say 20 thou in 10 inches, for instance, but such a bow is a distinctly "non-flat" condition for our purposes.

rollin45
11-29-2009, 12:14 PM
Evan,,this is great information!!

I'm 1949 vintage and haven't expired and I am glad of that, and glad you posted this.

rollin'

Evan
11-29-2009, 12:43 PM
Not at all true. If you derive a benefit from it, i.e. you use it, you have deprived the patent holder of the income he otherwise could have gotten from you (directly or indirectly). Therefore your private use of the patented process or device is exactly equivalent to selling a product based on it with no license, just on a much smaller scale.


That is correct for an unexpired patent. However, there is a principle that makes it unenforceable in practice. Since there is no commercial gain if used for personal use only, the most that a patent holder can do is to notify the infringer to "cease and desist". Actual damages cannot be collected as they cannot be enumerated. A lost oppourtunity to sell you a license cannot be counted as actual damages since it cannot be shown that you would buy such a license. Only punitive damages can be collected and only from the date of notification of infringement. It is also impossible to "conspire to infringe". Only actual infringement is actionable.

At any rate the information I have used is all from prior art that has long since expired or was never patented at all.

boslab
11-29-2009, 12:47 PM
mt companies spend an awful lot of time looking at other companies patents, mainly to rejig them to bypass the patent process, thats life i'm afraid as far as patents are concerned its a case of print and be dammed i,m afraid.
most of the world does not a] follow Christian principles and b] respect intellectual property [methinks britain and America rate quite highly in the ignore the patent bit too.
Apart from that the Electropolishing recipie from Evan is brilliant, it gets around a difficult problem, worrying weather its sombodies patent?
copied any music lately? maybee the odd photocopy of a book? [copyright is law too]
mark

DFMiller
11-29-2009, 12:58 PM
Evan,
I am following this thread with much interest. Sometimes listening is a good thing. Keep up the good work. Dave

bborr01
11-29-2009, 01:10 PM
Hi Evan,

I too am interested in your work. I am filing it away with the posts about de-rusting through electrolisis.

Handy information to know when the time comes that one needs it.

Keep up the fascinating work.

Brian

SDL
11-29-2009, 01:22 PM
i want you to scuff a bit a stainless up with 100 grit paper ..then do the polishing process ..
only then will i be convinced .

where the hell do you get phosphoric acid from cheap ?

all the best.markj

That will give you very shiny scratches. We mirror polish the inside of the UV chambers to 15 Ám (16RA") then electropolish, you can see you face like a mirror. The outside we do with 120 grit and it is very bright but full of lines and no reflection.

The process also increases corrosion resistance.

Steve Larner

aboard_epsilon
11-29-2009, 01:44 PM
That will give you very shiny scratches. We mirror polish the inside of the UV chambers to 15 Ám (16RA") then electropolish, you can see you face like a mirror. The outside we do with 120 grit and it is very bright but full of lines and no reflection.

The process also increases corrosion resistance.

Steve Larner

thats what i thought ..only capable of taking the peaks off and smoothing the troughs of the scratches ....just the same as using 1000 grit on 100 grit scratches and never really getting anywhere ..because it has to be done stage by stage.

what final grit gives you 15 Ám (16RA") ?

all the best.markj

lazlo
11-29-2009, 02:06 PM
More accurately, they are a wealth of information... from which you can't derive income.

Market the mixture, you have a problem. Use it in your garage, no problem.

Not at all true. If you derive a benefit from it, i.e. you use it, you have deprived the patent holder of the income he otherwise could have gotten from you (directly or indirectly). Therefore your private use of the patented process or device is exactly equivalent to selling a product based on it with no license, just on a much smaller scale.

Jerry's right -- according to US patent law, you're allowed to make a copy of a patented device "for instructional purposes" (essentially, to prove that the device actually works), but using the device is patent infringement, even if you're not deriving income from it.

That's not just hair-splitting for HSM'ers -- when we were crawling through the FogBuster patent on PracticalMachinist, several people posted pictures of the copies they made based on the rec.metalworking analysis of the patent, and they're just asking for trouble from FogBuster...

Evan
11-29-2009, 02:12 PM
The most Fogbuster can do is issue a cease and desist order. They haven't lost any revenue so they can't sue for damages.

At any rate it makes no difference as I am not infringing any patents. I am really surprised that anybody can even get a modern patent on electropolishing. There are so many expired patents that just about any combination of electrolytes and additives are covered. It draws directly from electroplating which goes back to the Babylonians so there is a very large body of prior art.

Peter N
11-29-2009, 02:12 PM
Decided to edit this out to avoid thread hijacking

SDL
11-29-2009, 02:14 PM
thats what i thought ..only capable of taking the peaks off and smoothing the troughs of the scratches ....just the same as using 1000 grit on 100 grit scratches and never really getting anywhere ..because it has to be done stage by stage.

what final grit gives you 15 Ám (16RA") ?

all the best.markj

600 then compound from memory

Steve Larner

boslab
11-29-2009, 02:47 PM
That will give you very shiny scratches. We mirror polish the inside of the UV chambers to 15 Ám (16RA") then electropolish, you can see you face like a mirror. The outside we do with 120 grit and it is very bright but full of lines and no reflection.

The process also increases corrosion resistance.

Steve Larner
toilet cleaner in the uk
mark

QSIMDO
11-29-2009, 04:49 PM
I may have to see how this would work on the SS exhaust pipes of my bike.
They were never "polished" to begin with so they've gone beyond the amber that SS turns to and are now just brown.

Might prove to be difficult to locate a SS container large enough and CHEAP enough to hold pipes though.

Evan
11-29-2009, 04:58 PM
You may be able to at least remove the burnt tarnish by using a sponge that is tied to a stainless steel "paddle" and connecting the positive to the bike and the negative to the paddle. Saturate the sponge and wipe the sponge slowly over the pipes. Simple tarnish comes off in seconds so far as I have seen to date. I am going out to do some more experimenting shortly and will see how it works on burnt SS.

I'll be posting the micrographs a bit later too.

lazlo
11-29-2009, 05:16 PM
The most Fogbuster can do is issue a cease and desist order. They haven't lost any revenue so they can't sue for damages.

They can sue you for the cost of a FogBuster. By building, and using, the FogBuster described in their patent, you have deprived them of $500 of revenue.

Very unlikely, but if you have a thread with 30 posts, like we had on PM, where everyone was showing their copy of FogBuster's patent...

hoof
11-29-2009, 05:49 PM
Count me in as intrested, With nothing to add I to will use my refind command of the english language and say nothing at all.

Hoof

Weston Bye
11-29-2009, 06:06 PM
Evan,
Haven't anything to add, except that I am interested in your outcome working with aluminum.

Blueskys
11-29-2009, 06:34 PM
It draws directly from electroplating which goes back to the Babylonians so there is a very large body of prior art.

I wonder what the Babyloners used for the electro part of the plating
process. Some kind of chemical/battery reaction?

Great discussion. A humbling reminder of how little I know/understand about
so many things.

EDIT: Persian Batteries made of clay with iron and copper for anode/cathode and vinegar
for electrolyte? Remnants have been found but some dispute over whether
they were actually electrical devices.

Michael Hall
11-29-2009, 06:47 PM
There is a good post on rec.crafts.metalworking discussing this very subject, it is from a few years ago. If my link does not work search RCM using "electropolishing recipes" the author is Carl Ijames.

http://tiny.cc/PAqXj

Michael

lazlo
11-29-2009, 06:51 PM
There is a good post on rec.crafts.metalworking discussing this very subject, it is from a few years ago. If my link does not work search RCM using "electropolishing recipes" the author is Carl Ijames.

http://tiny.cc/PAqXj

That's a great post/recipe! Seems pretty simple -- very similar setup to electrolytic rust removal or electrolytic cleaning.

Evan
11-29-2009, 06:57 PM
They can sue you for the cost of a FogBuster. By building, and using, the FogBuster described in their patent, you have deprived them of $500 of revenue.


They would have to prove that you would have bought one, They can't. In fact, the fact that you built one is evidence you wouldn't buy one. They can't establish intent on your part and they can't make a case for damages that didn't occur. The only way you can deprive them of revenue is to take the revenue yourself.

Evan
11-29-2009, 06:59 PM
Here is the micrograph of the faceplate.

http://ixian.ca/pics6/polish8.jpg

dp
11-29-2009, 07:17 PM
They can sue you for the cost of a FogBuster. By building, and using, the FogBuster described in their patent, you have deprived them of $500 of revenue.

Very unlikely, but if you have a thread with 30 posts, like we had on PM, where everyone was showing their copy of FogBuster's patent...

How many pages of off-topic bickering will the herd take this thread? I'd bet it's good for 300 posts just on patent foolishness.

lazlo
11-29-2009, 07:27 PM
How many pages of off-topic bickering will the herd take this thread? I'd bet it's good for 300 posts just on patent foolishness.

If you want to kiss Evan's butt some more Dennis, you can do it in the Swine Flu thread.

Evan
11-29-2009, 07:28 PM
They can start a new thread. My recipe isn't patented so the point is moot.

lazlo
11-29-2009, 07:31 PM
Here is the micrograph of the faceplate.

http://ixian.ca/pics6/polish8.jpg

That's pretty amazing. How well does it work with aluminum?

The standard "Brite Dip" (aluminum electrolytic polish) formula is pretty similar:

ALTERNATIVE TO BRIGHT DIPPING (http://www.ep-systems.com/aboutme1.htm)

Historically, aluminum has been and is still brightened using the aluminum bright dip bath. This bath consists of about 71.5% phosphoric acid, 10% aluminum phosphate, 10% water, and 2.5% nitric acid. Sometimes sulfuric acid is added, about 6 to 10%. The bath runs at 225 to 240░ F. Nitric is a volatile acid and must be added each hour to the bath. Nitric acid also forms nitrogen dioxide, which is a yellow fume that is toxic; therefore, a fume suppressant, such as diammonium phosphate, is also added to the bath to break the nitrogen dioxide down to nitrogen and oxygen. This bath requires a shrouded hood with slots going up to the height of the racks being pulled out of the tank. The parts give off nitrogen dioxide in the air and the fumes must be sucked off into the exhaust hood and into the fume scrubber. There are about 17 variables that have to be controlled each hour to produce bright, pit-free aluminum. Plant corrosion is very bad.


They can start a new thread. My recipe isn't patented so the point is moot.

I was replying to Tony Ennis' comment that it's OK to copy a patent if it's not for profit. That's definitely not true.

Evan
11-29-2009, 07:46 PM
Robert,

Anything with nitric acid isn't similar or safe in the home shop. Nitric is a very agressive acid and can cause very prompt and serious burns. I make sure my chemical recipes are environmentally benign and don't present a disposal problem. We are more acutely aware of that than most since we treat our own sewage on site on this property in a sewage lagoon about 30 feet in diameter. As long as it doesn't get contaminated with things like bleach the bacteria and algae stay healthy and it has a pleasant green plant smell as well as frogs living in it. I would like it to stay that way.

I haven't done any real tests yet with aluminum. The testing is a slow process because the solution heats too easily. It will need a double bath cooling system the same as I use for anodizing but I don't want to go that far right now.

Right now I am letting the solution cool for another test, this time a cleaning test of a heat discoloured SS tube.

Evan
11-29-2009, 08:19 PM
Here is the toasted SS tube test. I cooked the tube on the gas stove until it was dull red heat. After cooling it went in the bath at 24 volts for about 10 minutes, right end only in the image. The foam bubbled up so I had to cut it short but the piece was developing a nice shiny finish at the right end which is closed to the bottom of the bowl. Another 5 to 10 minutes and it will be all shiny for the half that was in the bath. The left half received some cleaning action too because it was covered in charged foam.

http://ixian.ca/pics6/epolish9.jpg

jkilroy
11-29-2009, 10:11 PM
I am looking forward to trying this on aluminum. Evan how would you suggest protecting threads, in my case blind holes with 3/8x16 thread. Run in a bolt? could this process be used before anodizing without ill effect?

Evan
11-29-2009, 10:43 PM
I just finished supper and am going out to the shop to try some aluminum. I will report later.

lazlo
11-29-2009, 10:49 PM
I just finished supper and am going out to the shop to try some aluminum.

Evan, the other thing I'm curious about: how does the initial surface finish (on either SS or aluminum) affect the final surface finish? If you were to lightly polish the surface with sandpaper, and then electropolish it, it seems like the leveling effect of the eloctropolish would give you an even finer surface finish, as opposed to a billet finish, where you're leveling rolling hills and valleys in the material.

DigiSnapMark
11-29-2009, 11:12 PM
I'll bite... I'm an engineer, not an lawyer, but here's my take.

The patent system is intended to disseminate new technology ideas... not to hide them. A US patent is a public document, intended for the general public to look at, to gain knowledge of new inventions. There might be some copyright issues with freely copying patents around the place, particularly if you just show excerpts, but they are never intended to be secret!!!

The original idea was to encourage publishing your inventions, by giving you 17 years of exclusive license to the invention. If not for this system, you'd have most inventions closed up in notebooks somewhere, to keep them secret, and technology advancement would crawl.

There's absolutely no incentive for any patent holder to sue someone for infringement if you use their idea for your own entertainment, or build 10 for your friends. If you start making loads of money off a currently patent protected idea, and they find out about it, and decide they want to give a lot of money to lawyers, maybe they'd sue, and in some cases maybe even win. It's rather expected that if even if you are 'in the field', you're going to build that invention, play with it, and see if you can work around some of the patent 'claims' to circumvent the patent.

HSM'ers should never worry about infringing... People who try to make LOTs of money off of a patented idea might.

Evan
11-29-2009, 11:14 PM
I am sure that would be the case. This works at a very fine scale so if the scale is small to start with then it will carry on from there. I have a piece of floor scrap aluminum in the bath right now.

Evan
11-29-2009, 11:20 PM
I am slightly bored so I'll reply with one factoid.


It's rather expected that if even if you are 'in the field', you're going to build that invention, play with it, and see if you can work around some of the patent 'claims' to circumvent the patent.



In order to be considered infringing the item you make/use must incorporate every single one of the claims made either exactly or as a substantially and functionally exact substitute. For instance, I have left out sulphuric acid in my solution and that immediately makes it non infringing to any electropolishing bath that uses sulphuric acid.

Evan
11-30-2009, 12:37 AM
Aluminum: It cleans aluminum well but it does not level the surface. I am pretty sure that is because it doesn't have any sulphuric acid. I am pretty sure it would work well as a brightener and polish if the bath contained sulphuric acid.

However, it works very well to clean and brighten mild steel. It appears it will work well on any ferrous alloy.

TheAndroid
11-30-2009, 12:15 PM
Great minds think alike. I messed with this a few years ago:
http://www.metalworking.com/dropbox/_2003_retired_files/EPolish_Info.txt

There are several places where you can find adequate Phosphoric Acid. I've even experimented with hydrated DPSO(?). It reaches a ph of around 2.3 which is consistent with the 85% Phosphoric Acid solution I initially used.

When I did put Al in the bath, I got mostly the same cleaning action you are seeing. I seem to remember high current and high time in the fluid finally produced a mirror finish. For the amount of time it took, I think traditional polishing would be more effective.

aboard_epsilon
11-30-2009, 12:32 PM
Great minds think alike. I messed with this a few years ago:
http://www.metalworking.com/dropbox/_2003_retired_files/EPolish_Info.txt

There are several places where you can find adequate Phosphoric Acid. I've even experimented with hydrated DPSO(?). It reaches a ph of around 2.3 which is consistent with the 85% Phosphoric Acid solution I initially used.

When I did put Al in the bath, I got mostly the same cleaning action you are seeing. I seem to remember high current and high time in the fluid finally produced a mirror finish. For the amount of time it took, I think traditional polishing would be more effective.

Yep, but the point is :- traditional polishing is blinking hard work ,tedious...and dangerous if you have an funny shaped item on the wheel....hard to get into knucks and crannies..
That's why I'm interested.

all the best.markj

Peter N
11-30-2009, 01:35 PM
Yep, but the point is :- traditional polishing is blinking hard work ,tedious...and dangerous if you have an funny shaped item on the wheel....hard to get into knucks and crannies..


You should see some of the mould cavities we have to polish Mark. Very hard work and all done by hand without buffing wheels, as we can't chance taking too much off and a wheel can be a bit uncontrollable.
Have a look on e-bay for a **** (reciprocating, not rotary) as I imagine they come up occasionally - this might help you.

Peter

J Tiers
11-30-2009, 10:37 PM
I am slightly bored so I'll reply with one factoid.

In order to be considered infringing the item you make/use must incorporate every single one of the claims made either exactly or as a substantially and functionally exact substitute. For instance, I have left out sulphuric acid in my solution and that immediately makes it non infringing to any electropolishing bath that uses sulphuric acid.

Likewise, and the answer really is "it depends".

You do not need "all" the claims, but you need all the claims linked by "and"...... Most patents have several "trees" of claims, with variations. Usually these will emanate from a base claim, which is normally the first.

Claim one might be "A floszzy widget comprising A, and B, and C, having D, and E, and F."

Claim two might be "the floszzy widget of claim one with G and H."

claim 3 "the ... of claim two with ........ " and so forth for many other claims, based directly on claim one, or based on any of the other claims.

if you make a floszzy widget comprising A, and B, and C, having D and E and F, you infringe, as you have made the claimed device. The fact that claim 2, 3.... through 35 are not involved, is of no matter. Any added things you incorporate are of no matter.

but if the claim says that the widget comprises items a,b,c,d,e,f,and g, while you leave out e, you MAY be not infringing. it depends on whether the patent can be said to anticipate leaving that out.

if the patent appears to have "e" as an important feature, you are likely OK, although it might cost you to prove it. You may have superseded the "prior art" which "teaches" the necessity of "e".

if the patent does not seem to depend on 'e", it might be found to be a variation "obvious to one skilled in the art", and still be covered.

Regardless, the act of making and using a patented device for your own purposes, OR for commercial purposes, constitutes infringement, aka thievery.

A private thief is unlikely to be caught, but he is still a thief.

personally, I think electropolishing is interesting, and potentially useful, if reasonably easy to do, as it seems may be the case. At the moment I have no application, but I expect I will someday.

The guy who posted about making taillights a few months ago might need to read this thread....... I bet it would improve the reflectors... weren't they turned aluminum?

Evan
11-30-2009, 10:55 PM
if the patent does not seem to depend on 'e", it might be found to be a variation "obvious to one skilled in the art", and still be covered.


I love that little bit of patent boilerplate. All it really means is that "If you think of something I didn't and I can somehow stretch my claims to include it then I might try to take it away from you..."

It really doesn't mean much and is included in every patent. Go to court and you will be restricted to what you claimed.

tdmidget
12-01-2009, 01:42 PM
Evan if your stainless has Cobalt 60 in it you have way more problems than disposal of used solutions. Note the Oak Ridge article was for solutions used on IRRADIATED items. If you have Cobalt 60 in yours you need to get your affairs in order.

J Tiers
12-01-2009, 11:47 PM
Go to court and you will be restricted to what you claimed.

But you won't, because you don't have the $2 million door charge. That was the estimate we were given.

That boilerplate was intended to avoid the "pink wheelbarrow" effect, small "technical" changes meant to evade a patent. They get slapped down regularly.

Of course these days the patent office will issue you a patent on air, or the doorknob...... they don't do any research, apparently. I've found prior patents that would be infringing on recently issued patents..... BOTH WERE ACTIVE AND IN EFFECT.

Nevermind......

Nobody is going to bust your door down for infringement by contraband electropolishing in your garage, regardless of whether or not it is a "real" infringement.

And I think in Kansas you are allowed to own books without paying the tax on them now, too. I had heard they used to be taxed.

Evan
12-02-2009, 01:38 AM
From the search that I did I don't think it is infringing anything simply because of the prior art in electroplating and electrocleaning.


Anyway, I am doing some more testing. I have diluted the solution considerably and am using only 12 volts instead of 24 to see what happens. Processing times will be longer but results may be better. It may be a few days before I have anything to report but when I do I will post it.

davidfe
12-02-2009, 07:58 PM
Evan,

I too appreciate the posts and the extensive information.

Regards

Kiwi
08-18-2015, 04:55 AM
Fantastic post Evan thank you

CCWKen
08-18-2015, 09:09 PM
Did you just wake up from nearly a six year coma? :)

metalmagpie
08-19-2015, 12:44 AM
zombie