Femtocopper from a thermobox

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Aleman

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Ok this is how I converted my 34.5L Thermobox into an electric copper for the small 20L femtoplant. Some steps are still missing, but it will be added to as I find the piccies :lol:

DISCLAIMER: MAINS ELECTRICITY AND WATER ARE A DANGEROUS COMBINATION, IF YOU ARE NOT CONFIDENT WORKING WITH SUCH, GET A COMPETENT PERSON TO DO IT FOR YOU.

I decided I wanted a sight glass, so after levelling the thermobox I dangled a weight on a piece of cord to determine a true vertical. That was marked on the masking tape Note the existing hole where the original tap was positioned. Using a 6mm Cobalt Drill and plenty of water as a coolant a hole was drilled right through at the top and bottom. Then switched to a 25mm Cobalt Holesaw and (again with lots of water as coolant/lubricant) I drilled through the inner skin. This was repeated at the top. A 15mm Q Max punch completed the holes on the inner skin (Not shown), and a 3/8" custom nipple fitted (details in another post somewhere . . . don't think its on here yet) Top and bottom.

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Now to fit the element, this is a water boiler element from The heating element company (Backers), and was chosen because it is a) 3KW and b) it only requires two 13mm holes to fix it securely in place . . . and I have a 12.5mm QMax Punch. There is an issue however, the end of the element actually protrudes through the outer side wall, and mixing electricity and wort is something you always need to be aware of. What I decided to do was to get an IP56 project box from Maplin, cut the bottom off, radiused to fit the curve of the inner skin, which would give that extra headroom.

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First job, is to mark out the appropriate sized hole near the base of the outer skin, and a hole drilled with a 6mm Cobalt drill bit (and plenty of coolant) in each corner. Then using my trusty angle grinder with a stainless steel slitting disc. I carefully cut through the inner skin
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Before prising off the stainless steel covering to reveal the foam underneath. Some work with a sharp craft knife, saw the insulation encouraged to leave, and it was removed in short order.

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My Favourite 6mm cobalt drill bit was then used to drill a pair of holes at the appropriate distance apart, before punching out with the 12.5mm QMax punch, and a 'little tickle' with a grinder on the Dremel meant that the element was fitted in short order.

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With the element in place it is time to fit the project box (the hole to the left is for the PT100 Probe which I use to maintain the temp while running off before switching power on to bring it to the boil). The outer hole needed a little bit of work with the grinder on the Dremel and a needle file to make it fit tightly. Once this was done the foam was coated with Food Grade silicone sealant and the Project box put in place and again liberally coated with sealant.

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Wiring this element is simplicity itself. Firstly, one of the nuts is undone, and a M13 automotive crimp connector connected to the earth wire is put in place, followed by a brass washer and the fixing nut . . . this is screwed down firmly . . . and then earth continuity checks carried out. Crimp connectors are attached to the live and neutral wires which are then bolted down on the stud terminals at the end of the elements. The other end of the Lead is passed through an IP66 Rated cable gland and out to a 16A commando connector to connect to the mains.. . . . At this point it is probably wise to check Earth continuity and leakage . . . Luckily my boiler passed both :party:

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Hope this helps . . . I'll try and get the missing bits added . . . like hop stopper/ Tap and sight gauge and the PT100 Probe. somethime soon
 
I think that this is the **** :cool:

Guys, please back me up, Aleman = unloved :(

T - :thumb:
 
Excellent work as always Tony, dedication and attention to detail as always.

Your Family must constantly think who is this strange man that lives in the shed & keeps coming in and out of the our house muttering obscenities to himself, rooting through the drawers, & shouting "eureka I've got it" just when a good bit of eastenders is on is. :lol: :whistle:

Aleman "Blackpool's arm of the Blichman research lab!"

UP
 
Sorry for zombie thread resurrection :D

Aleman - I have just ordered the same element and am about to fit it to my 65 litre stock pot. I've got some proper heat rated flex to connect, but I was simply going to put a 13a plug on the end - why did you fit a 16a Commando connector?
 
MikeB said:
I've got some proper heat rated flex to connect, but I was simply going to put a 13a plug on the end - why did you fit a 16a Commando connector?
Simply because I didn't have the space in the control box to fit 3 pin sockets . . .but Commando panel mount sockets fitted fine.

Plus 16A Commando Connectors are big and butch mans connectors :rofl:
 
Aleman said:
MikeB said:
I've got some proper heat rated flex to connect, but I was simply going to put a 13a plug on the end - why did you fit a 16a Commando connector?

Plus 16A Commando Connectors are big and butch mans connectors :rofl:

Oh well that's a fine reason :D
 
Can I point out that these plugs are not fused so please fit an inline fuse, or a switched FCU before the commando socket. Like I does innit.
 
I would maybe go for a metal box/guard as these plastic boxes are usually abs and not rated for boil kettle sustained temperatures of 100oC.

I would also look at drilling the 2 holes vertically rather than horizontally and use a narrower box which would elimate the hassle of radiusing the box, on a 500mm pot 50 is only a chord h-1.25mm versus a 100mm chord h of over 5mm.

On saying that it is tricky finding a narrow box, I plan to use a 100x100x 50 drill out the box only where needed and jb weld or like rather than silicone onto the kettle.
 
alby said:
I would maybe go for a metal box/guard as these plastic boxes are usually abs and not rated for boil kettle sustained temperatures of 100oC.

I would also look at drilling the 2 holes vertically rather than horizontally and use a narrower box which would elimate the hassle of radiusing the box, on a 500mm pot 50 is only a chord h-1.25mm versus a 100mm chord h of over 5mm.

On saying that it is tricky finding a narrow box, I plan to use a 100x100x 50 drill out the box only where needed and jb weld or like rather than silicone onto the kettle.


What difference does the junction box size/shape make? :roll: :roll: :roll:

If it Sheilds the connections from water and little fingers, then its doing its job, we are making home brewing equipment not CE marked, ready to market products.

I do subscribe to the metal box comment though as opposed to an ABS box :thumb: However if that route is taken make sure it is properly earthed

UP
 
unclepumble said:
alby said:
I would maybe go for a metal box/guard as these plastic boxes are usually abs and not rated for boil kettle sustained temperatures of 100oC.


I do subscribe to the metal box comment though as opposed to an ABS box :thumb: However if that route is taken make sure it is properly earthed

UP


HaHa I read ABS as "A Bit *****" :lol: :lol: :lol: Took me a minute to figure it out! :D
 
May have came across a bit grumpy last post as I couldn't find a tin or metal box that can be sealed last night.

First of all this is a truely great post, neat job and I am very grateful to the pictures and writeup, first class Mr.Aleman.

Another, good similiar how to is over here
http://www.theelectricbrewery.com/heati ... nts?page=7

Back to the topic....

- plastic box on silicone may be ok, but it does get tricky identifying the plastic type/material and how it behaves at sustained near to 100oC

- yes I agree, probably the main purpose is finger protection so I'm not sold completely on an IP boxed
(even if I get one I'll drill a drain hole in the bottom just in case the kettle to pot leaks in the way to the box

- yes, this is the main earth point for the kettle and junction box. Even though it is for own use etc, it's something I would make a mental noet to test with some degree of regularity.

Finally, I'd suggest to use a butyl rubber flex cable which is 3183TQ or cooker/hob cable to everyone else. This covers you up to 85 oC. Add a further braid if you are still worried.

Finally, finally is anyone jealous or have a source for those american 5500w ULWD heater/elements that are under $20 in home depot and can run dry without blowing.
 
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