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Does Size Really Matter

PostPosted: Wed Aug 02, 2017 8:03 pm
by Kenster
Hoping to raise some interest with the subject heading...

Until recently i have been more than happy with my converted Still spirits 25lit boiler...(extra 3kw element)
Well, as you all know, there is only so much you can fit into one of those, and given that i usually make up a 60 to 70 lit wash, the need for two runs has become a bit of a pain.
If i were to replace it with aprox 80lit boiler... could i, run it 'efficiently' with say, a 20 or 30lit volume of wash, if i did not wish to run it full up. I guess my concern is that, if it is half full, with all that head space internally, would the vapours travel up the column just as efficiently as a full run. Am i defeating the purpose of having a larger boiler, and if the need arises, to run it at non-full capacity.
So is the size important... regarding how much is NOT in the boiler, will it alter the way the column stacks once it gets up there. This is based on that i 'might' need to run it at less than capacity. Normally, i would not intend to. I intend to throw 2 x 3kw elements at it with controllers.

Re: Does Size Really Matter

PostPosted: Wed Aug 02, 2017 8:06 pm
by Doubleuj
As long as your elements are submerged by the end of the run it won't matter if you do a small run. But if you're going to build a bigger boiler why not make a simple pot still to go on top? Or better still, a bubbler :music-deathmetal:

Re: Does Size Really Matter

PostPosted: Wed Aug 02, 2017 8:11 pm
by copperhead road
:text-+1:

Re: Does Size Really Matter

PostPosted: Wed Aug 02, 2017 8:20 pm
by Kenster
Thx...i am currently running a 1500mm x 3'' pot, and similar VM/LM Combo, so my pipes is good...just a smallish boiler.

Re: Does Size Really Matter

PostPosted: Wed Aug 02, 2017 8:39 pm
by db1979
A bigger boiler that's less than full will heat up slower than a smaller boiler with the same volume of wash given the same parameters of insulation, heat input and wash type (abv etc). This is because of all the extra metal that needs to be heated up and because a bigger boiler will suffer more heat losses given its bigger surface area, hence the greater importance to insulate it.

If you can get away with one boiler though to do everything you need then why not go for a bigger one?

WJ is on the money. Once you have experience with a wash and know how much you can expect out of it you can make a pretty safe guess at how much volume will be lost from the boiler during the run and then work out what your boiler's minimum volume is to cover your elements. Add about 10 - 20% more than this as a safety factor and you're good to go.

Re: Does Size Really Matter

PostPosted: Wed Aug 02, 2017 9:12 pm
by cattery
An insulated 50lt keg boiler seems like it would be a happy medium for you. Thats what i run with my 70lt washes i put down two at a time so i get two 50lt runs and a 40lt one.

Re: Does Size Really Matter

PostPosted: Thu Aug 03, 2017 6:44 pm
by Kenster
db, thanks man, i was assuming that i would need to throw more power at it coz of the larger surface area etc., so that was always in my mind, as was my understanding of keeping the elements fully covered. My biggest concern was the large overhead volume (emptyness?) ... would it screw up the way the vap was formed and travel up the column. Guess i thought some serious turbulence and passive reflux may impact in that cavity before it started its trip up north. But i suppose it will eventually do what it is supposed to do.
cattery, i see what u mean by a compromise, size / vols to be run etc.. but am going to steer clear of kegs as my height limitations will cause just too many mods. The unit i am looking at is 400 high and will suit my current setup.

Re: Does Size Really Matter

PostPosted: Thu Aug 03, 2017 10:05 pm
by db1979
You could do a keg on its side, I think Dog Breath Vodka made one a few years ago.

Re: Does Size Really Matter

PostPosted: Thu Aug 03, 2017 10:53 pm
by Sam.
Vapour will fill the void and keep going upwards, on hobby size stills this won't be a problem at all.

If you start talking industrial refinery type columns then yes every bit counts.

Re: Does Size Really Matter

PostPosted: Fri Aug 04, 2017 6:00 am
by Sparrow
Well my missus tells me that size doesn't matter and I mean...hang on :shifty:

I run a 50l boiler and even at that I've been wanting to upgrade to bigger. Just don't feel it's enough after all the time it takes to ferment a wash and run it, the little bit extra time for a bigger wash to run saves more time in the long run than doing them.separate.

I've done 25l washes in my boiler and I don't feel like it takes that long to heat up either.

Re: Does Size Really Matter

PostPosted: Fri Aug 04, 2017 7:02 pm
by hillzabilly
Ifn I was a major rum or even whiskey fiend,I would make a boiler with extra head space to counteract the foaming and pukeing issue's,wich in my opinion is a problem with maxing out ya boiler running those wash's,I run a 80lt boiler and have never had any probs with 25-50lt runs ,a bigger boiler may take slightly more time ta heat up than a 25lt one but my 80lt has more than double the power available than my old 25lt one ,so the opposite is true I can heat a 30lt run in it faster than I could heat a 25lt run in a small boiler,and I like the fact that a short fat boiler is more stable when running tall heavy stills.cheers hillzabilly :handgestures-thumbupleft:

Re: Does Size Really Matter

PostPosted: Fri Aug 04, 2017 7:08 pm
by copperhead road
Sparrow wrote:Well my missus tells me that size doesn't matter and I mean...hang on :shifty.


:text-+1: missus reckons bigger da betta :laughing-rolling:

Re: Does Size Really Matter

PostPosted: Thu Sep 07, 2017 6:52 pm
by Kenster
Sorry for the late reply, but thanks Hillz... that is exactly what i was thinking and hoping to hear...Cheers

Re: Does Size Really Matter

PostPosted: Sat Sep 09, 2017 6:52 am
by Aussiedownunder01
This is a 80 litre keg with a 30 litre welded on top 100 litres can run from 30 litres to 90 litres all bases covered

Re: Does Size Really Matter

PostPosted: Sat Sep 09, 2017 3:38 pm
by Professor Green
That is a marvellous boiler mate. Love the wood insulation.

Cheers,
Prof. Green.

Re: Does Size Really Matter

PostPosted: Sat Sep 09, 2017 6:53 pm
by Nino
Professor Green wrote:That is a marvellous boiler mate. Love the wood insulation.

Cheers,
Prof. Green.


:text-+1:

Re: Does Size Really Matter

PostPosted: Sun Sep 10, 2017 8:18 pm
by Kenster
Aussie., i think i recall following the build...nice one man.
To all, thx for the input...appreciated.