Weld-Free Electric Keg Boiler: A How-To Guide
Posted: Thu Oct 23, 2008 5:46 pm
up untill a few months ago i had been using a 20L stockpot with a bokakob plate column. it worked well but was a pain to seal up with flourpaste all the time and could only do pretty small runs. heres a thread about how i made the original column...
http://homedistiller.org/forum/viewtopi ... =17&t=6594
so for the past few months ive been upgrading my rig. this thread will be a guide on how i made my electric keg boiler. this can be used with any reflux column or pot still head you please. it requires no welding or special exuipment so you can do it completely yourself over a weekend. i havent seen much on this topic so hopefully this will help some of you guys out in the future!
PARTS:
-keg
-screw-in hot water heater element (preferably low density)
-bolt on heating element flange (home depot)
-refletix insulation 2X24 ft home depot
-4 stainless nuts/bolts/washers
-1/8" music grade cork corkstore
-2 inch tri-clamp brewhaus
-tri-clamp to NPT couple brewhaus
-2" copper female couple (mcmaster.com #5520K26)
these are the exact parts and suppliers i used, but use your imaginations.
to start will need to cut 5 holes into your keg. put these as low as possible to help prevent your element becoming exposed during a run. basically take your flange and line it up against the bottom skirt on the keg. mark out the 5 holes on the flange and cut them out. this is the hardest part by far. stainless steel wont cut very easily. for the large center hole,I ended up using a dremel with one of the metal cut off wheels and it worked like a charm. you will have to use a 1/4" drill for the 4 bolt holes and it will take a bit of time, i found that a slow speed and a LOT of pressure worked best. just be careful as you near the end and watch that it dosent catch as you break through and twist your wrist.
next, you will have to remove and replace the rubber gaskets that come with the heating element and the flange. follow the golden rule, NO PLASTICS.
to replace them,cut a square of your cork that is at least an 1/8 inch bigger all around then the flange. then trace out the inside of the center hole and use an exacto knife to cut it out. at this point the cork will probably not fit over the flange, thats ok, just keep trimming small ammounts off till you can just squeeze it around the neck of the flange. the cork is a bit stretchy and will give a nice snug fit if you do it right. S. im not sure if this is 100% necessary but it worked for me.
you will use the same idea for the bolt holes. just take the tip of your exacto and spin it around and sort of drill a hole through the cork. then take your bolts and washers and push it through leaving a nice tight seal.
you can now bolt the whole thing onto the keg. leave the element out so you can reach through the center hole to attach the nuts. the cork should sort of squish out the sides under the flange when you get it nice and tight. finally you can put in the heating element. you will need a large monkey wrench to torque it down. they also sell special wrenches for a few bucks for this right next to the elements.
be sure to ground the keg!
at this point you can stop. but to really maximize your boiler you will want to add insulation. i used refletix insulation from home depot because it is waterproof, cheap, and insulates both conduction and radiation. the 2X25 foot roll works perfectly for a keg. start by cutting out some circles that fit into the top and bottom of the keg. make them a tad oversized so they will be snug and hold themselves in. you should use 2 layers on the top nd bottom. you can then insulate your column if you like, it will only use a few inches of your roll. then just take whats left over and wrap it around the sides. the side of the keg is just under 2 feet so it works perfect without any trimming needed. i ended up with about 5 layers on the side. dont worry about overkill, the more insulation the better. besides what else are you going to use it for? even with 5 layers it is only about an inch thick. on my rig the insulation is cool to the touch even when running full-blast. good for safety as well as not wasting heat.
i ended up taping the top and bottom edges together then slicing down the side to get a c-shaped shell of insulation. this lets you remove it easily for cleaning. the top and bottom circles will just pop right out too. the insulation itself it water-proof. during a run i hold it on with 2 loops of wire.
finally, you can use the leftovers of your cork sheet to make a gasket for the keg-column seal. basically just trace out a ring, dosent need to be exact at all like before. the tri-clamp connects the keg to the male adapter which screws into the female adapter soldered to your column. it would also be possible to do it directly to the keg if you could find the proper fitting.
NOTES:
-use the highest wattage element you can find. i used a 5500W and it will strip a full keg from a cold-start in under 2 hours easily. just make sure you have a safe setup if you need to use 240V
-use a low density element if you can. the larger the physical element is the better, this means more surface area and lower heat/in^2 which means less scorching of solids -some people have claimed cork can be used to substitute cork.
http://homedistiller.org/forum/viewtopi ... =17&t=6594
so for the past few months ive been upgrading my rig. this thread will be a guide on how i made my electric keg boiler. this can be used with any reflux column or pot still head you please. it requires no welding or special exuipment so you can do it completely yourself over a weekend. i havent seen much on this topic so hopefully this will help some of you guys out in the future!
PARTS:
-keg
-screw-in hot water heater element (preferably low density)
-bolt on heating element flange (home depot)
-refletix insulation 2X24 ft home depot
-4 stainless nuts/bolts/washers
-1/8" music grade cork corkstore
-2 inch tri-clamp brewhaus
-tri-clamp to NPT couple brewhaus
-2" copper female couple (mcmaster.com #5520K26)
these are the exact parts and suppliers i used, but use your imaginations.
to start will need to cut 5 holes into your keg. put these as low as possible to help prevent your element becoming exposed during a run. basically take your flange and line it up against the bottom skirt on the keg. mark out the 5 holes on the flange and cut them out. this is the hardest part by far. stainless steel wont cut very easily. for the large center hole,I ended up using a dremel with one of the metal cut off wheels and it worked like a charm. you will have to use a 1/4" drill for the 4 bolt holes and it will take a bit of time, i found that a slow speed and a LOT of pressure worked best. just be careful as you near the end and watch that it dosent catch as you break through and twist your wrist.
next, you will have to remove and replace the rubber gaskets that come with the heating element and the flange. follow the golden rule, NO PLASTICS.
to replace them,cut a square of your cork that is at least an 1/8 inch bigger all around then the flange. then trace out the inside of the center hole and use an exacto knife to cut it out. at this point the cork will probably not fit over the flange, thats ok, just keep trimming small ammounts off till you can just squeeze it around the neck of the flange. the cork is a bit stretchy and will give a nice snug fit if you do it right. S. im not sure if this is 100% necessary but it worked for me.
you will use the same idea for the bolt holes. just take the tip of your exacto and spin it around and sort of drill a hole through the cork. then take your bolts and washers and push it through leaving a nice tight seal.
you can now bolt the whole thing onto the keg. leave the element out so you can reach through the center hole to attach the nuts. the cork should sort of squish out the sides under the flange when you get it nice and tight. finally you can put in the heating element. you will need a large monkey wrench to torque it down. they also sell special wrenches for a few bucks for this right next to the elements.
be sure to ground the keg!
at this point you can stop. but to really maximize your boiler you will want to add insulation. i used refletix insulation from home depot because it is waterproof, cheap, and insulates both conduction and radiation. the 2X25 foot roll works perfectly for a keg. start by cutting out some circles that fit into the top and bottom of the keg. make them a tad oversized so they will be snug and hold themselves in. you should use 2 layers on the top nd bottom. you can then insulate your column if you like, it will only use a few inches of your roll. then just take whats left over and wrap it around the sides. the side of the keg is just under 2 feet so it works perfect without any trimming needed. i ended up with about 5 layers on the side. dont worry about overkill, the more insulation the better. besides what else are you going to use it for? even with 5 layers it is only about an inch thick. on my rig the insulation is cool to the touch even when running full-blast. good for safety as well as not wasting heat.
i ended up taping the top and bottom edges together then slicing down the side to get a c-shaped shell of insulation. this lets you remove it easily for cleaning. the top and bottom circles will just pop right out too. the insulation itself it water-proof. during a run i hold it on with 2 loops of wire.
finally, you can use the leftovers of your cork sheet to make a gasket for the keg-column seal. basically just trace out a ring, dosent need to be exact at all like before. the tri-clamp connects the keg to the male adapter which screws into the female adapter soldered to your column. it would also be possible to do it directly to the keg if you could find the proper fitting.
NOTES:
-use the highest wattage element you can find. i used a 5500W and it will strip a full keg from a cold-start in under 2 hours easily. just make sure you have a safe setup if you need to use 240V
-use a low density element if you can. the larger the physical element is the better, this means more surface area and lower heat/in^2 which means less scorching of solids -some people have claimed cork can be used to substitute cork.