Douglefish

Recipes 

I am using an Electric Boil Keggle made from a 1 in stainless nut and a 5500W ULD heating element. I'm getting rust on the base of the heating element, and some is transferring over to the stainless steel. Just wanted to get peoples thoughts.

Is this a problem?
Is there a way to avoid this?

Thanks for the help!

david_42

Recipes 

Definitely a problem as wort is acidic and will dissolve the rust giving your beer an iron/metallic taste. Try cleaning the rust off and treating the area with a rust converter. This will give you an insoluble protective layer. You may have to do this several times.

__________________
Remember one unassailable statistic, as explained by the late, great George Carlin: "Just think of how stupid the average person is, and then realize half of them are even stupider!"

"I would like to die on Mars, just not on impact." Elon Musk

AiredAle

Recipes 

You have a couple solutions you can try. Some folks have cleaned up the rust on the element base and the kettle, then coated the element base with silicone sealant. The solution I chose to use was to buy a magnesium fire starter at a camping store, cut it in half, and bolt it to the inside of my HLT (where I had the problem). I used a stainless steel 1/4" bolt, drilled a hole in the kettle, put the bolt in from the outside, silver soldered it to seal it, then put the magnesium block on the protruding threads inside the kettle and tightened it down with a stainless nut.

The magnesium is a sacrificial anode, and should prevent the steel of the element base from corroding, because it is a more active metal and will corrode first. You could also use a piece of aluminum, but I chose magnesium because I don't want aluminum ions in my water or beer, but don't care about magnesium ions.

Another choice would be to replace the element with a stainless steel one. Lowes has some, though I am not sure if the base is stainless or not. Next time I'm going there, I'll take a magnet and see.

Douglefish

Recipes 

Do you have any recommendations as to what rust converter to use?

Thanks again

ScubaSteve

Recipes 

From what I've read, the base of almost every element is mild steel. This is independent of the element's material. You could use more of the JB weld you used to pot your connections, and just create a thin protective layer.....or just go with the food grade silicone sealant. A sacrificial anode sounds complicated, but it isn't....you already have to drill holes in the pot...I think even copper will work

__________________
UNIBREW 5500 SINGLE VESSEL BREWERY
WOODEN SINGLE TIER

beerocd

Recipes 

So, a copper dip tube would solve the problems? Or it actually has to touch the mild steel?

__________________

Due to recent economic crisis, stock market crash, budget cuts, and the rising cost of everything including taxes: "The Light at the End of The Tunnel" has been turned off.

ScubaSteve

Recipes 

Actually, the idea is that you need to have 2 things:

1) An electrical pathway for electrons to travel...
2) The sacrificial anode must be more active than the metal you are protecting

Not sure if copper is less active than mild steel, especially once it forms an oxide layer.....

Aluminum is hella cheap and easy to drill...I say go for aluminum

__________________
UNIBREW 5500 SINGLE VESSEL BREWERY
WOODEN SINGLE TIER

jkarp

Recipes 

Or use an aluminum pot. Never had the slightest trace of rust in my e-kettle and it's a couple years old now.

beerocd

Recipes 

So the Coghlan's firestarters(most common brand) are composed of:
97.24% Magnesium
1.21% Zinc
1.11% Manganese
0.44% Iron

The electrical pathway is the water.
Still unclear if I have to bolt it in, or can I just toss in the firestarter and fish it out upon cleanup?

__________________

Due to recent economic crisis, stock market crash, budget cuts, and the rising cost of everything including taxes: "The Light at the End of The Tunnel" has been turned off.

AiredAle

Recipes 

I bolted mine in place. This assured me of electrical contact. Take a look at "Cathodic Protection" on Wikipedia. The electrical path is through the metals and through the water in the pot. Pity, since I always wanted to bolt a chunk of zinc in the trunk of my car and prevent rusting.

Copper isn't active enough to protect steel according to the activity table in Wiki, but aluminum is just barely active enough.