Electropolishing Welds on Stainless.

[rwm]

I am interested in doing this. After some research it seems like Phosphoric acid would be the best electrolyte. 85% H3 PO4 is pretty cheap on eBay. I have ordered some carbon fiber to make a brush. Does anyone have experience with this?

Check this out:

DIY Stainless Steel Weld Cleaning / Electropolishing

DIY Stainless Steel Weld Cleaning / Electropolishing: When stainless steel is heated to welding temperatures, it turns lots of pretty colors - gold, red, purple, blue - depending on the temperatures. These look nice, but if you want your stainless steel to look like stainless again, a polishing...

www.instructables.com

Robert

 

[Rootpass]

I’ve done it at the house with a car battery charger. Works well generates heat! I’ll see if I have a picture.

 

[Rootpass]

It’s been rolling around in my desk drawer. 304 3/4” round stock. It works pretty quick. As a side note, I’ve seen where it’s said you can electropolish aluminum too but I never had any luck with it.

 

[middle.road]

I am interested in doing this. After some research it seems like Phosphoric acid would be the best electrolyte. 85% H3 PO4 is pretty cheap on eBay. I have ordered some carbon fiber to make a brush. Does anyone have experience with this?

Check this out:

DIY Stainless Steel Weld Cleaning / Electropolishing

DIY Stainless Steel Weld Cleaning / Electropolishing: When stainless steel is heated to welding temperatures, it turns lots of pretty colors - gold, red, purple, blue - depending on the temperatures. These look nice, but if you want your stainless steel to look like stainless again, a polishing...

www.instructables.com

Robert

Adding to my 'Wanna-Do' list - you are. . .

 

[vtcnc]

Make sure you consider a neutralizer and then rinse the neutralizer from your work. You will leave a residue if you don't neutralize and rinse. Sort of like a sticky salt build up and it can stain your work-piece.

If you are going to do this as a matter of trying to make money, use separate rags to neutralize, rinse and dry. Cross-contamination can happen pretty quickly when weld cleaning in volume.

 

[rwm]

I ordered some Phosphoric Acid and some carbon fiber cloth to make a brush.
Pics to follow....maybe...
Robert

 

[homebrewed]

I'm puzzled on why you need to make a carbon fiber brush. The Instructables article uses a stainless steel cathode with fiberglass or a special sponge around it to hold the electrolyte. You don't want direct contact between the work and cathode, that will just short the power supply out. Am I missing something?

 

[rwm]

I'm puzzled on why you need to make a carbon fiber brush. The Instructables article uses a stainless steel cathode with fiberglass or a special sponge around it to hold the electrolyte. You don't want direct contact between the work and cathode, that will just short the power supply out. Am I missing something?

I agree! I saw the instructable setup. I see that the commercial units use carbon fiber brushes. I think the fiberglass wrap does not conduct well enough. Does anyone know the best solution?
Robert

 

[vtcnc]

This is the wand we have on our Walter Surfox Weld cleaning system at work (or at least something that looks very similar to this one):

Walter 54B029 Highly Conductive Carbon Fiber Flow-Through Brush 5Pk

Ideal for tight corners, narrow surfaces and hard-to-reach areas.

www.emisupply.com

The carbon bristles burn up over time. The way it was explained to me is that the electrolyte flushes any debris away and the bristles allow for flow through conductivity and the bristles conduct into the little wrinkles and crevices of welds.

With a felt pad, the pads have to be dipped into the electrolyte solution. The felt conforms around the weld bead. So I don't think there is a worry for a shorting problem here, it is more about using a conductor that conforms to the contours of the weld you are cleaning.

EDIT: perhaps there is something different going on when using the carbon brushes. I'll take a look at our model tomorrow and tell you which one we are using exactly and you can look up the specs.

 

[rwm]

I cannot believe the prices of the Walter stuff.
Robert