Mild Carbon Steel Sulphuric Cell _sulfuriccell_

[philddreamer]

Thank you, 4metals!
I started the tumbler a couple of days ago, but wanted to work out any bugs on the cooling system before working on the tumbler.
I still need to add some holes in the bowl, glue the pipe in place, set up the anode...

So, the agitation is what speeds things up? When I rotate the tumbler, the items tend to "ride" the bottom... do I need to add a fin? I didn't notice any on the videos of the tumbler. (My PC freezes everytime after a few minutes of trying to look at them).

Indeed! I will share pic's and details of the cell after I finish setting it up.

Thanks to all!

Phil

 

[4metals]

Plating barrels of this type are called oblique barrels and the parts stay on the bottom half of the basket as it turns. (gravity has a funny way of being consistent) The dangler which makes electrical contact with the loose parts tends to break them up as they tumble around and make and break contact with the dangler.

 

[philddreamer]

AHAAAAAA!!! :idea: :mrgreen:

Thanks!

 

[kurtak]

Very Cool Phil 8) 8) 8)

Kurt

 

[goldsilverpro]

Nice setup, Phil.

In many areas of Washington state, it's quite humid. Strong sulfuric, especially, absorbs moisture from the air. In a non-moving stagnant solution, the lighter water absorbed tends to float, thus diluting the sulfuric, considerably, at the solution level. This diluted sulfuric can attack the steel slowly, creating an etched indentation in the steel at the solution level. Stirring often and covering the tank when not in use can help alleviate this problem. A tumbler would provide constant agitation. Also, keeping the temperature at a low level will reduce the attack. You could also vary the solution level, periodically. Some sort of masking might work, but there are not many things that will stand up to the strong sulfuric - maybe some sort of wax designed for masking in a plating situation. Lead tape would would stand up but the adhesive probably wouldn't. Both lead tape and masking wax are sold by plating suppliers.

You may or may not have etching problems. It's something you should definitely keep your eye on, though.

When I used a 50 gallon mild steel tank for this purpose, it was in L.A., where the humidity was quite low. After at least 2 years of daily use, there was no visible etching at the surface level.

A few links of a fairly heavy chain might serve well as a dangler contact.

 

[Anonymous]

Phil, if you welded that up, those are some nice beads brother.

Smack I am totally with you on this. I'm jealous- my welding looks like ratsh*t.....

 

[goldsilverpro]

Concerning the possible etching discussed in my previous post, I just thought of something else. You could reinforce the steel at the solution level by welding strips of steel sheet all around the inside of the tank. I'm thinking strips about 1/8" thick X 1" wide, centered at the solution level.

 

[geedigity]

Good idea! That way it would take a long time to dissolve the "sacrificial" plate, and not the tank itself.

 

[Anonymous]

Concerning the possible etching discussed in my previous post, I just thought of something else. You could reinforce the steel at the solution level by welding strips of steel sheet all around the inside of the tank. I'm thinking strips about 1/8" thick X 1" wide, centered at the solution level.

The same theory as sacrificial anodes on the hull of a warship Chris right?

 

[g_axelsson]

Concerning the possible etching discussed in my previous post, I just thought of something else. You could reinforce the steel at the solution level by welding strips of steel sheet all around the inside of the tank. I'm thinking strips about 1/8" thick X 1" wide, centered at the solution level.

The same theory as sacrificial anodes on the hull of a warship Chris right?

No, no electrochemical potential here, just making the metal thicker so it would last longer.

Göran

 

[philddreamer]

Very Cool Phil . Kurt

Thank you, Kurt!

GSP wrote:

Nice setup, Phil.

Thank you, Chris!
I did covered the tank with a plastic bag and tied a strap to seal it from the air. It's hot and dry, so a feel moisture shouldn't affect much... I hope!
Thanks for the etching details!!! I'll keep a close eye on the matter.
I'm working on a tumbler, and hope to have it up and running soon. What is the recommended R.P.M's. for the tumbler!?
During the 2.75 hr. test run, the temp stayed below 75 degrees.
I'll be looking into the masking wax.
I'm already looking for some chain!!! :mrgreen:

Concerning the possible etching discussed in my previous post, I just thought of something else. You could reinforce the steel at the solution level by welding strips of steel sheet all around the inside of the tank. I'm thinking strips about 1/8" thick X 1" wide, centered at the solution level.

I'm already planning building another tank in the near future, and that will be considered. When I clean this one, I'll add some strips.
Thanks againg, Chris!

spaceships wrote:

Smack I am totally with you on this. I'm jealous- my welding looks like ratsh*t.....

Practice, practice, practice!!! 8)

I thank you all for your interest and expert advice!!! 8)

Phil

 

[goldsilverpro]

You don't want the tumbler turning too fast. Maybe about 5 RPM.

 

[philddreamer]

Thank you, Chris!

What would be the recommended length of the chain?

 

[Anonymous]

Concerning the possible etching discussed in my previous post, I just thought of something else. You could reinforce the steel at the solution level by welding strips of steel sheet all around the inside of the tank. I'm thinking strips about 1/8" thick X 1" wide, centered at the solution level.

The same theory as sacrificial anodes on the hull of a warship Chris right?

No, no electrochemical potential here, just making the metal thicker so it would last longer.

Göran

You're right Goran clumsy wording on my part. But think around it, what if you could put something on there that effectively took the erosion preferentially over the chassis itself?

 

[g_axelsson]

I don't think sacrificial anodes inside the sulfuric acid would work. To be working it would have to be active and not passivated by the acid and anything that could be dissolved would go quickly in the acid.

Göran

 

[philddreamer]

Some pic's showing the progress on the tumbler!

Phil

 

[jason_recliner]

Looks great. Just an idea for your upcoming patent:
Assuming the lower lip of the colander is below acid level, consider the design idea for some very small angled plastic blades - an impeller of sorts - to help ensure acid in the bowl is continuously replaced. By gently pulling fresh acid in the top, dissolved/powdered gold would flow out the holes more readily.

 

[philddreamer]

Thanks for the tip, Jason!
There's always fresh acid, as I turn the tumbler...

I also need to tack weld most of the links in the chain, except the bottom one, so it can make better contact.

 

[Smack]

That stainless chain Phil? Or is it zinc plated? Or maybe just plain, can't tell in the pictures.

 

[philddreamer]

The chain is just of plain steel...