keg to electric kettle conversion

[bellybuster]

hellow all, thought I'd post as I go with my keg to kettle conversion.
I'm starting with a standard 15 gallon sanke keg


The element will go through the side via a 1" NPT coupling available anywhere. I got mine cheap from FleaBay


Now be aware that most elements are not NPT threads but NPS threads. The difference is in the taper. The element can be screwed into the NPT fitting a good way with a healthy dose of teflon tape wrapped around the threads. Brewers have been doing this for many years successfully.

More to come very soon

[bellybuster]

in order to get the coupling into the keg, one must drill a hole. The outside diameter of the coupling is around 1.5" so I used a 1.25" Bi-metal hole saw in my drill press. I had to rotate the table out of the way to make room for the keg

Bi-metal is necessary, stainless can be hard to drill but the Bi-metal goes through like butter. Another option is a step bit.

Now I have a hole in my keg down near the bottom. You need it close to the bottom to ensure it will never be above the liquid in your boiler. Initially the hole was too small, this was planned. In order to get a good solder joint you need to use a dremel or files to sneak up on the right sized hole. Go slow and check often. I have my hole sized so I have to force the coupling in tight.


My setup will be soldered in. I will be using a lead free silver based solder. The soldr I have is Oaty safe-flo silver solder. Make sure it has a minimum of 5% silver and is lead free.


The most important aspect of soldering stainlees steel is the flux. It needs to be specific for stainless (acid based). I will be using Harris Stay-Clean. I got mine from FleaBay


As I am waiting for my flux to arrive this will have to wait. Once it's here I'll go thru the joint preparation and the actual soldering. If I can I'll do a video of the actual soldering.

[Butterman]

Looking good.
Video would help people out so much, its hard to describe explicitly what can be shown.
Would love to see a video and Ill make some popcorn :>

Butterman

[hillbillywilly]

Cool can't wait to see the rest of the build

[Richard7]

I didn't know this could be done with soft solder. I was under the impression that it had to be brazed with stick silver solder. Looking forward to the video.

[bellybuster]

sure can be done, takes some trial and error.
here's a very long thread on the subject
http://www.homebrewtalk.com/f51/solderi ... el-155782/

[bellybuster]

let's talk about choice of element.
There are a few different types out there. The best choice for a boiler is a "Ultra Low Wattage density" element. The watt density has no bearing on how fast the water is heated a 4500 watt element would put the same number of btu's into the water just the length of the element changes with the low watt density element being much longer. This means the wattage per inch of element can be lower, this in turn lowers the risk of scorching
example;
a 4500 watt element of 10" long would put out 450 watts per inch, the same 4500 watts over a folded back style element would consume a much lower wattage per inch due to it being longer. That's the short answer.

For my keg, I have purchased a Camco 4500 watt Ultra Low Watt density element. I would have preferred to go 5500 watts but they are rediculously hard to find in Canada.


Remaining chapters are yet to come as items arrive in mail.

[Butterman]

Your 4500 watt element is rated for 240 volts but can be used with 120 volts. Which voltage will you be using and what will you be using to control the amps the element draws?

Butterman

[bellybuster]

I'm also building a controller and will go 240volts. There is another thread out there with my controller build based on this

[bellybuster]

let's now look a bit at preparing the joint for soldering. Other than having the correct flux, this is probably the most important aspect.
The hole in my keg is sized so that I need to press my coupling in with considerable force. Not so much as I need to hammer it in but I need to push quite hard and it will stay there on its own.
I also filed a bit of a bevel around he outer edge of the hole as a place to hold solder. Assuming I'll be able to get the solder to stick this should make for a very solid joint.



For now, that's it for prepping. As I do not yet have my flux I don't want to get into sanding. If I did, the stainless would just repassivate and I'd have to do it all over again. The key to a good bond is having clean virgin steel to stick to. If I were to expose it now an oxide layer would build up in a very short period of time

[Butterman]

Im really enjoying your documentation of the process BellyBuster, very informative :>

[bellybuster]

ok folks, joint preperation time. I forgot to take a pic so start imagining.
Satainless steel when scratched, scoured or anything that breaks the surface loses its non corrosiveness. (I just made up that word). Good thing about stainless is it will repassivate very quickly when exposed to oxygen. This is good in one respect, bad in another. It means to us that after prepping the keg and coupling we need to get busy with the soldering so there is no time for the stainless to start oxidizing.
Anyway.... the joint and the area around it need to be clean and sanded until virgin metal is on the surface. I used 320 grit aluminum oxide paper on mine and sanded a couple inches around the hole until it was good and shiney, then I sanded a little bit more for good measure.
The coupling needs to be sanded as well. Now for the coupling it needs to be in your hand so I wear cotton gloves to avoid the oils from my hand contaminating where I just spent time cleaning and sanding.
Now that everything is nice and clean you can mate the coupling with the keg for soldering. Again with the gloves.
Size up a ring of solder by wrapping it around the coupling.
Now it's flux time. Using a brush of sorts apply a liberal amount of flux to both the keg and coupling, then place the solder

Soldering is easy, first I gently heated the area around the joint by giving a few passes with a low torch (propane). This just puts some warmth into the keg itself. I believe the heat will transfer better this way.
The actual joint will be heated thru the coupling, slowly. Aply the heat with a low flame to the inside of the coupling trying to evenly heat all the way around. Once you see the flux starting to heat good stop with the torch and reapply flux. Careful of the vapours, they are nasty!!. Now continue with the low flame to the inside of the coupling, keep it moving. You will eventually reach the melting point of the solder.
Once the solder fully melts and flows, remove the heat. Don't be tempted to give it that little extra.
I did make a video and it is loading to youtube as we speak but it will take awhile.

[hillbillywilly]

Nice explanation on process. Can't wait to see the video.

[Butterman]

When are we getting the link to you video -Ill start making popcorn-

Butterman

[bellybuster]

Link to video, sorry its 6 minutes but .........
Don't mind the mess, I'm renovating.

http://m.youtube.com/watch?v=BBZPocvNt8M

[bellybuster]

I'll get a pic up later of the joint, worked perfect.

[bellybuster]

and..... voila!! we have a perfectly soldered coupling, no tig welding, no special equipment.

[Condensifier]

Nice tutorial and video bellybuster, thanks. I've never soldered stainless so I'm going to use your method on my keg when I go electric soon.

BTW I couldn't access the video through your link so I searched your user name on youtube and found it that way. I'm not sure what the reason was but neither I.E. or Firefox would work with your link.

[bellybuster]

Hmmmm, opens fine for me

[Condensifier]

Not sure why it don't work for me. I tried I.E. 8, Firefox and Google Chrome and no go.

Here's the link I used: http://www.youtube.com/watch?v=BBZPocvN ... fA&index=1 in case others are having the same issue.

[hillbillywilly]

Nice can't wait to try soon!

[Richard7]

[Theo]

Bellybuster,

U tube spelled your name wrong, it was Bellyuster on the vid. Maybe that was the problem. Good video!

[bellybuster]

Haha, that was a typo by me many years ago.

[Butterman]

Very nice video and I cant stress the importance of the way you would stop and reflux the area to be soldered. Great job, you should have taken a bow at the end :>

Butterman

[Truckinbutch]

Thank you very much for this info . Solved a fabrication problem I ran into .
Also , thank you Richard7 for pointing me in this direction .

[bellybuster]

My pleasure Gentlemen, I don't take credit for the method. I'm doing two more keg glues today, converting my brewery to electric as well

[Antaean]

Bellybuster,
GREAT thread, got me to change my mind about my heat source for my next still to electric.......now I have to do research on which and where to find the heating element

[bcboyz86]

Oh man, this is way easier than I thought it was going to be...and all I would need is the coupler, an element, and the controlling box that goes to a 220 plug? The people who owned our house before us put a few in the garage so this would be awesome!

[Butterman]

Belly did a real great job showing how to accomplish this.
Your plug can be 220 volts or 110 depending on what size and voltage element/elements and controller you use.
Personally I think 110 is more portable for use, but if you have a large boiler and a permanent or semi permanent location 220 is the way to go.

Butterman