I trialled one-pot style systems recently, but the 3-Vessel approach is still my personal favourite. So the plan is a 3v system, plus an underback, that will both store compactly and function in a narrow kitchen. I've a glycol cooled & warmed fermenter with about 64L (14 gallon) working capacity, so that is roughly the maximum volume of wort to comfortably produce (in any normal, say <1.065, gravity beer).
Work has begun with the kettle. Allowing for evaporation and subsequent losses (dead-space, shrinkage, hop retention etc.) the pre-boil volume will be around 85L, a bit more with hoppy brews. I could top up to offset evaporation but don't really want to, and don't want to risk spills either, so a pot volume of around 100L or so would be needed. I chose a 110L Tabec pot from Brouwland, a tiny bit bigger than needed but, at about 450mm diameter, its relatively small footprint was perfect for my needs (and it isn't too tall for me to just reach the bottom):
Although it looks nice, IMO it is a similar quality to the thin Bergland stock-pots, and the dust cover is unimpressive as a lid (it sort of perches on, not very securely). But it is the shape that led me to choose it over the cheaper Bergland alternatives.
The bottom was slightly (probably not intentionally) dished, so the bottom-centre is where I decided to put the drain. A pick-up tube could be used with the syphon effect, but for neatness and ease of rinsing out I preferred a bottom drain. An MDF tool was made (not unlike a q-max cutter, but to press rather than cut):
Some bits of steel were used as big backing washers, and the tool was closed together with an M16 bolt and big spanners in order to dimple the (previously flat) base. A thru-hull fitting was then put in with little deadspace:
The brass things are bulkheads for some rod elements. There will be two 2.5kw low watt-density elements which will run around the circumference of the base, partly to leave the centre free for large hop filters and partly to avoid interference with any whirlpooling.
To keep the footprint small, the pump, electrical boxes and water-resistant powercon mains connectors etc will be mounted under the pot. To allow easy mounting of these and the legs, a moisture-resistant grade of OSB was glued to the pot base, using white 'Sticks like' (an additional thickness of OSB was later built up under the legs). Some clearance was allowed around the element bulkheads, but the last two inches of the elements are unheated so overheating shouldn't be a problem unless run dry by mistake.
This will not be seen when finished so the slightly crude aesthetics don't concern me.
It had some legs screwed on and the pump placed underneath. There will be a (grainfather style) riser tube leading directly up from the pump outlet; there won't be a valve to reach or clean (when in use in the narrow kitchen, the MT will likely be in front of the kettle). Here it is set up with some temporary insulation for testing.
The pump (which I already had) is a good one but quite loud on the floorboards of the flat. So it was hung on four (blue) bits of silicone hose; the otherwise rigid pipework also had silicone links in to help isolate the noise and vibration. The results are quite a bit better.
The headspace seemed sufficient, a little skimming of the foam needed, but not much:
The boil was quite convincing. I (now) understand that one of the main reasons for a vigorous boil is to help particles to collide and clump together; lots of that going on here:
Ultimately I intend a large mesh whole-hop filter, but currently have lots of pellets. So a kind of garden sieve was made with #40 mesh base to help contain the trub after whirlpooling it into the centre. You can't see it but there is a tee in the outlet beneath the sieve, effectively turning the centre outlet into two edge outlets. It worked fairly well, some trub settled around the edges, but the majority was in the middle and the sieve basket stopped it spreading out again when the wort was drawn off.
The rod elements can also be seen running around the circumference. In retrospect I may have gone for shorter ones; 4 feet or so would have likely been enough to spread the heat and stop burning stuff on, these are twice that so a little more cramped. But at least they are very easy to clean with just a soft cloth.
The test was pretty successful, the only issue was relatively minor and encountered when cleaning rather than in use. With shallow volumes, a vortex is prone to form, which then lets the pump suck air through the central drain. This won't be a problem in normal use with hop or pellet filters/sieves in the way, but I may make a cover or elbow for the outlet for when cleaning.
) for a flat kev! very impressed with the tooling and general build quality.
