Has anyone tried aluminum electrodes?  It is my understanding that these do not corrode in water, and are a LOT cheaper...

Also saw a guy on youtube using 316 SS foil.  He was having great success using Dry Cell, 2.5 liter per minute at 12A 12V.

Just heard about a coating process called Carbon Raptor Coating.  It's for automotive applications, applies a 2-4 micron thick layer to any metal, can even be used inside a cylinder so I assume it's good for electrolysers.

I built a working PWM using the LM324 FINALLY.  100% fully adjustable duty cycle, variable frequency too.  ONE chip, ONE board, NO decade switching, 8 resistors and one capacitor, total for under $10.

Will post details soon on my site

the problem with aluminum is the aluminum oxide coating on all aluminum exposed to air or water. during the electrolysis process, the aluminum oxide has a tendency to dissociate from the aluminum plate, thus resulting in short life plates. this also happens with stainless steel, which is why such things as foil and thin coatings would not be ideal. in stainless steel, the plate corrodes, but at a slow rate. ideally, a electrolysis device should be made form a material that corrodes, but this means that the electrodes must be replaced, so HHO devices use less corrosive materials, a plate coated in platinum or gold would be best for HHO developers. i have also heard that a compound that contains aluminum is being looked at for generating hydrogen on demand, i think it also contains gallium.

There is pretty good explanation.

Have you seen stainless steel tubing corrosion naa...
Aluminum is pretty good at "corrosion"  I do not really know about all types of it but ... it does corrode.

Just do as i did. Take a aluminum spoon and use t as electrolyte. Soon you will notice that water is not clean.

Not all grades are corrosive there are many marine Vessels and Fishing Boats  that are used in Saltwater and show very little corrosion
we used a lot of 6061T6 on our Submersibles and 316L SSl and this combination did not even produce an electrolysis to the point of being destructive. Then there is a Alcan alclad Aluminum I believe it was 2024 it was impervious to corrosion as long as you did not scratch its coating.
I had a higher Gas output using one Alu and one SS rod than just all SS.
If you use any Chemicals you make a good halfwave rectifier that way. Perhaps you can then eliminate the HV Rectifier used by SM?
professor

Hey wizard, keep that kinda crap somewhere else, you make me paranoid man...

So how about this coating?  I just talked to a guy who sells a coating, 2-4 microns thick, 10^9th ohms, he can't do tubes very well because it's hard to reach the inside but he said a 3" tube with 1"ID would probably be ok. 

Will not dissolve under voltage.  Can't we substitute this for the oxide layer?  I personally do not have a month to spend flicking a switch and changing water in a conditioning cell.  And I would probably screw it up anyway.

About this resonance... it seems to me that the longer our coils, the easier it will be to attain resonance... imagine a pendulum hanging from the ceiling... the longer the rope, the easier to keep it going.  However for all practical purposes we should probably be aiming to ring the tubes until a Phase Lock Loop utilizing a pickup coil can sustain resonance for us. 

Hey wizard, keep that kinda crap somewhere else, you make me paranoid man...

So how about this coating?  I just talked to a guy who sells a coating, 2-4 microns thick, 10^9th ohms, he can't do tubes very well because it's hard to reach the inside but he said a 3" tube with 1"ID would probably be ok. 

Will not dissolve under voltage.  Can't we substitute this for the oxide layer?  I personally do not have a month to spend flicking a switch and changing water in a conditioning cell.  And I would probably screw it up anyway.

About this resonance... it seems to me that the longer our coils, the easier it will be to attain resonance... imagine a pendulum hanging from the ceiling... the longer the rope, the easier to keep it going.  However for all practical purposes we should probably be aiming to ring the tubes until a Phase Lock Loop utilizing a pickup coil can sustain resonance for us. 

As to the Coating it comes that way from the Manufacturer the 2024 is very strong but brittle  or lets say not very flexible you can not bend it which would be O.K. for our purposes. However if you shear it you will expose the ends which are then uncoated and must be insulated with whatever.
I had purchased some Waterglas  Na2SiO3 for the purpose of coating the Plates but have not used it yet.

Alclad is a trademark of Alcoa used as a generic term to describe corrosion resistant Aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded to high strength Aluminium Alloy core material. These sheets commonly used by the aircraft industry[1].
Described in NACA-TN-259, of August 1927, as "a new corrosion resistant aluminum product which is markedly superior to the present strong alloys. Its use should result in greatly increased life of a structural part. Alclad is a heat-treated aluminum, copper, manganese, magnesium alloy that has the corrosion resistance of pure metal at the surface and the strength of the strong alloy underneath. Of particular importance is the thorough character of the union between the alloy and the pure aluminum. Preliminary results of salt spray tests (24 weeks of exposure) show changes in tensile strength and elongation of Alclad 17ST, when any occurred, to be so small as to be well within the limits of experimental error."
professor

Hi ,

I have been playing with waterglass and the Hutchison crystal battery this year.

 In all cases the Alu dissolves when it touches sodium silicate. (It makes H₂ bubbles when it does this.) .  It may take 30 minutes, but the terminals all pull away.

So, try it on a piece of scrap Alu just to prove it to yourself first. Don't waste a good build or even a piece of aluminum.

I have been thinking about HHO generation all day. Most threads agree not to use brute force, but to pulse the dc. I've been thinking it might work to switch anode and cathode at the same time you pulse the cell. Then the corrosion which is really a matter of electroplating one terminal to the other, will stop, because you are switching endlessly.

I suppose it all depends on how quickly the electroplating eats away at the one terminal... Maybe once a week is frequent enough to stop eating through the terminal.

jeanna

Hi Jeanna

 If I understand you right then we must have had the same thoughts on polarity reversal. You can do it cheaply with a Relay but you can only switch it as fast as the mechanical spring allows you.I had designed a Solid State Circuit on the Electronic Workbench a Design and Simulation Program for a different usage but it would allow to switch polarity ofl a DC voltage .
Beck uses that circuit for medical purposes only very low Power and switching and frequency
thanks for the advise on waterglas i did not know that it would react with alu........ interesting!
http://www.museum.wa.gov.au/collections/maritime/march/fallenangels/degrigny/fockewulf.html

During similar treatments performed on a Pratt & Whitney engine at the AWM, we found that sodium metasilicate Na2SiO3 was suitable because of its corrosion-inhibiting properties on aluminum alloys [10]; however, it was determined that, beyond a concentration of 0.08 M, significant corrosion occurred, with the formation of fibrous white aluminum silicate compounds. We therefore repeated these studies, establishing, in accordance with ANSI (American National Standards Institute) standard G-172, mass loss curves for aluminum-copper alloys (Figure 1) and aluminum-manganese or aluminum-magnesium-silicon alloys (materials commonly found in aeronautical wrecks) that are non-corroded and immersed in metasilicate solutions at various concentrations.
We found that the usable range of inhibitor concentrations (no evident corrosion) is broader for alloys without copper than for aluminum-copper alloys.
Originally I was wanting to use it on a couple of stainless rods to see at what voltage they would start conducting.
professor

Hi Jeanna

 If I understand you right then we must have had the same thoughts on polarity reversal. You can do it cheaply with a Relay but you can only switch it as fast as the mechanical spring allows you.......

Originally I was wanting to use it on a couple of stainless rods to see at what voltage they would start conducting.
professor

Hi professor,

I made a little proofofconcept for myself with a depleted 9 volt battery and 2 stainless washers held onto the batt with stainless wire. I added a tiny pinch of NaOH to the waterr and did the whole thing in an 8oz jelly jar.

The bubbles were prodigious while the battery remained above 6.5 volts.

But the part I think is important is that it takes a little while for the bubbles to form.

To me this means that a polarity shift would need to be fairly slow. Maybe the ideal switch would be an hour. (could be 24 hours) So, I would say that it wouldn't matter if you could not switch it very fast. And besides, you would fatigue the metal of the spring with too many switches. So, slow switching IMHO is better anyway.

It would still not corrode through the copper within an hour, and by reversing the polarity, what was lost from one terminal would be replated in the next hour .

On your other point, if the copper gets re-plated every switch, using specialized alloys could be just more expensive and troublesome, but not more productive.

However, if you have access to these alloys, please give them a try with a relay and report your results.

Here is my pep talk on reporting everything:
Good or bad, the results are what we need. I have learned a lot by my "failures" and you could save someone else a lot of trouble and expense if it doesn't work and you share those results. So there is never really a failure with something that doesn't work.

Enjoy,

jeanna

Has anyone tried aluminum electrodes?  It is my understanding that these do not corrode in water, and are a LOT cheaper...

Also saw a guy on youtube using 316 SS foil.  He was having great success using Dry Cell, 2.5 liter per minute at 12A 12V.

Just heard about a coating process called Carbon Raptor Coating.  It's for automotive applications, applies a 2-4 micron thick layer to any metal, can even be used inside a cylinder so I assume it's good for electrolysers.

I built a working PWM using the LM324 FINALLY.  100% fully adjustable duty cycle, variable frequency too.  ONE chip, ONE board, NO decade switching, 8 resistors and one capacitor, total for under $10.

Will post details soon on my site

Hi Farlander,

I would like to see your circuit.. sounds good!

Thanks,
Jason