the modern distiller

planning 4" plated, modular, need suggestions.

For all the plate variations out there, bubblecap, valved, perforated etc.

planning 4" plated, modular, need suggestions.

Postby amber » Tue Oct 18, 2016 4:30 pm

I am new member here and pretty new to distilling.
A friend suggested this might be one of the better forums to get some design advice/ideas/critiques, so here I go.

I am currently using a 2" copper pot still, which I made, which is going very well. Lots of fun, and despite having much to learn I am already making product I am very happy with.

I have started collecting copper for the next build and have been researching on what to do.

I want it to be a modular plated still- with (probably) two sections of plates that can be added or removed, depending on the desired product, and probably with a section of packing that can be swapped in instead of the plated sections for reflux and making neutral. Later on, possibly some sort of gin basket section that could be swapped in somewhere.

My primary interest is in whiskeys and rums, after that Gin and vodka/neutral from the rejected cuts (and some botanical stuff like absinthe and the likes).
Currently I am fermenting in 50L batches, two batches at a time, so I can strip both then nearly fill up a 50L keg boiler enough (at 40%abv) to warrant doing a spirit run. I like the idea of being able to ferment in single 50L batches and run it through a plated still and end up with finished flavoured product and with good heads and tails compression, in one go.

I currently have a nice clean length (1550mm) of 4" tube, with more available if required.
I also managed to collect a slab of copper 1/4" thick (6.35mm) which would give me enough round plate cut-outs to make up to 10 plates- I realise this is very thick for plates- it could be lathed down or I could buy some thinner plate to use (3mm or so).

I have access to tooling and the ability to TIG copper/stainless (same as I made my pot still) and am not too fazed about 'difficultly' of design, rather I am more interested in the best/easiest end function.

With everything below, I am open to suggestions:
for reflux condenser and product condenser I was thinking a shotgun style dephleg for RC and a shotgun for PC. Probably with the coolant water flowing in series from the PC through to the RC with a needle valve for control. Probably 4" dephleg and unkown size for PC (I do have some good bends and stuff in 2
For joining removable/modular sections I plan on welding on 4" flanges and using triclamps. Probably the same sort of approach for sight glasses?
For plates, I am leaning towards bubble caps as they seem a bit easier to control (will stay flooded). Not sure about numbers of plates for each section, or distance between plates. Not sure about general construction of plate tree, removability etc.

Some questions I have:
1. What is ideal thickness for plates? Is my 6.35mm slab of copper way too thick or might it have positive effects? I figure it would take longer to heat up (negative) but once hot might be more stable (positive?), but in the end I don't know. I do know my metal scrap yard of choice currently has a pile of 3-ish mm sheet, and I could get some of that instead, or during construction of my plates I could lathe/machine this thick stuff to a more optimal thickness.
2. Diameter of pipe for dephleg and the top U-bend and the product condenser- almost all versions of this kind of plated still I am looking at online seem to step dramatically down in diameter after the dephleg. Often it seems from a 4" column they will step down to 2" or smaller. Aside from cost of materials, is there a reason not to run full or close to full column diameter through to the PC? If not, what would be the optimum diameter for these things for a 4" column? For example, should it go 4" column, 4" dephleg, 2" U bend to 2" shotgun PC- or something else?

I have plenty more questions, but that is probably enough to get the ball rolling. I would greatly appreciate any discussion and suggestions of these issues, and/or any links to threads or other pages that might help. When I have the time I am reading and reading, but there is a sea of information out there and not all of it I find helps me very much.

Many thanks,
Posts: 4
Joined: Fri Sep 09, 2016 10:41 am

Re: planning 4" plated, modular, need suggestions.

Postby JayD » Tue Oct 18, 2016 4:58 pm

Welcome to the forum, please introduce yourself in the appropriate forum, I will provide a link back to this thread from your intro thread. :handgestures-thumbupright:
Posts: 1535
Joined: Mon May 06, 2013 8:58 pm
Location: Tasmania, home of world class Whiskey...

Re: planning 4" plated, modular, need suggestions.

Postby RefluxEd » Wed Oct 19, 2016 10:54 am

G'day Amber,
For a nice neutral I now use 12 x 4 inch plates. With 7 or 8 plates it was just possible to get a clean neutral but the run had to be incredibly slow with a very high reflux ratio. 10 plates is much better and 12 gives a great neutral. With this in mind I suggest you go for as many plates as possible and try to work in a plate bypass for adjusting the plate count for brandy and whiskey. That should provide a nice challenge for an inventive mind. 8-)
My reflux condenser uses 11 x 1/2 inch tubes inside 250mm long section of 4 inch copper with SS tri-clamp ferrules brazed onto it. This can knock back a 3 ring gas burner on full power. The good thing about a copper reflux condenser is that it is an efficient heat exchanger and is the last point where sulphides can react with copper and drop out before the vapours go over the top and into the product condenser.
And don't forget to make a parrot. An essential part of a reflux still. When doing a spirit run I stop when the ABV drops to 85%. If you go below that you get some nasty tails coming that ruin the batch. Don't bother making cuts as there is such a small amount of ethanol remaining in the pot that it is just not worth going to all that extra effort.
With this setup you can make a great neutral from a Tomato paste wash for making vodka, gin and absinthe or anything else that comes to mind.

With a 4 inch column reduce to a 2 inch pipe for going over the top and into the product condenser.
6mm copper for the plate does seem a little thick, the standard plates for 4 inch is about 1.6mm. I wouldn't worry about it taking longer to heat up, copper doesn't have a high specific heat so shouldn't be a problem.

Please post pictures of your build, it sounds like a great project.
2 inch BOKA/LM/VM
Bubbler with 14 4x3x4 inch tees and 15 bubble plates under a 4 inch section under the dephlagmator (RC).
2 inch Pot still.
2 inch to 4 inch Gin head.
2x 1.2 mtre Leibig condensors.
2 inch x 800 mm shotgun condenser.
Love it!
User avatar
Posts: 139
Joined: Fri Jan 17, 2014 6:10 pm

Re: planning 4" plated, modular, need suggestions.

Postby JayD » Wed Oct 19, 2016 1:58 pm

Firstly good idea asking these questions before you start to cut anything.
I would keep the cu plate for use in making your ferrules. If you have access to a lathe I would machine the ferrules to fit the od of your 4”, 2” and 3” tubes for their intended use then braze them to the tube.

I would then use copper from a section of cu tube flattened out to make the plates not forgetting to check for ovality in your tube your using for your sections. I would use 4” tube for my rc then via a 4” to 2” reducer from there I would use two 90* bends 2” for my pc may be leaving your pc a little longer for extra vapour knock down in lieu of bigger tube. Being a sectional still its up to you how many sections you have or have not to make your end product. Here is 4” one piece column we built for a member.
Perforated or bubble caps is like fords and holdens as personal choice, I use perforated with great success however many also use bubble caps.

You do not have the required permissions to view the files attached to this post.
Posts: 1535
Joined: Mon May 06, 2013 8:58 pm
Location: Tasmania, home of world class Whiskey...

Re: planning 4" plated, modular, need suggestions.

Postby amber » Wed Oct 19, 2016 10:06 pm

Great posts guys, this is really helping.

12 plates for good fast neutral eh? Ok, that sounds doable. And potentially of similar or less cost/effort/trouble as having a long enough section of packed column to swap in for neutral. I am trying to keep the still and boiler height below my low ceiling height in the garage under my house, but depending on the gaps between the plates I think 12 plates could be manageable. I am very much interested in trying to avoid the compromise of having to do really long runs to achieve the desired product- although if it is a compromise I have to make only for neutral then I could probably live with it as that is not my highest priority.

I have done a bit of reading over the last couple of weeks about plate bypassing, and it does seem to offer up some challenges. External or internal bypasses.. valves and sealing... etc.
I sort of figured it might be worth avoiding the ability of bypassing each plate and sacrificing a little bit of tunability/control and instead just make up multiple sections of different numbered plated column sections. A bit more work with ferrules and seals and triclamps, depending on the number of sections- less controll, but also less work and potential leaks with all the bypassing fabrication...? A toss up I suppose.
Question is what numbers of plates might be desired for different products- rum, whiskey, gin, fruit brandy, vodka? (happy to make some mild compromises here as long as the first two are optimised) Thus how many sections and what numbers of plates in each section?

Thanks for the dimensions of your RC, that is a great starting point for me.
Also, thanks for the reminder on making a parrot, I hadn't put that on the 'need to do' list yet. It is there now.
2" pipe after the RC is very doable, I just wondered if it was worth upsizing- I suppose with all the resistance in the plated section and the dephleg then 2" to the PC may not offer any significant restriction for maximum take-off?
I already have 2X 2" 90 degree bends for the top, a 4" to 2.5" reducer that I can alter to a 4" to 2" pretty easily, and a some other reducing stuff for the end of the PC.

thanks for the great picture- 1000 words and all.
Are those 3" sight glasses? Was this build documented in a thread somewhere?
I figured the 1/4" plate was going to be too thick. The problem with using it for making ferrules (access to a lathe isn't one) is that it is not wide enough- it is a tad under a meter long, and a few hairs over 4" wide (probably about 103mm or so). More than enough to make internal 4" plates from (9, maybe 10, depending) but not enough to lathe out some external ferrules for the 4".
It is no big deal though, if it doesn't find a use for this still then it can sit on the shelf (reminding me not to buy stuff before I have planned properly) and I can keep my eye open at the metal yards for something that will work, or just buy some weld-on ferrules that will work. On that note, I did have a lot of trouble silver soldering the stainless flange on my pot still to the column, but in the end we figured out how to reliably TIG braze copper to stainless and it was relatively very easy after that. So, some of the standard SS ferrules might offer a strong and neat solution and won't break the bank if I have to go that route.
Flattening out copper tube sounds like a good solution for the plate material.
When you say "may be leaving your pc a little longer for extra vapour knock down in lieu of bigger tube", does that mean that a bigger tube might be preferential?
I don't mind making a 'long' PC at all, a bit more copper which at scrap prices is fine, not trying to avoid that- I am very impressed with how small a trickle of water my hugely oversized PC on the pot still requires, even at full gas burn. However, if 2.5" or 3" or even 4" might be 'better' after the RC then I am just as happy to go with that. Although I have two 90 degree bends in 2" plus a few other bits to suit, I would be perfectly happy to leave them on the shelf and fabricate a TIG brazed 180 degree lobster back bend and other bits in whatever diameter pipe might be best.
On the other hand, on occasion I have a tendency to go about re-inventing square wheels- so if, as it appears, that going above 2" after the dephleg on a 4" plated column offers no tangible benefits, then I will just run with the 2".

For Bubble caps vs perforated plates- I am neither here nor there. The only main advantages from either I have picked up in my reading to date is that bubble caps will stay flooded if the heat drops, instead of dumping, and, for me at least, the perforated plates seem a little bit easier/straight forward to make. I am sure there is a lot that I am not getting yet though.
I have spent a little bit of time pondering what sort of perforated plate might be made from 1/4" copper plate... with or without some lathing to thin or profile/dish the plate... would the perforated holes stay the same diameter? Would it work better or worse than thin plates? Frankly I have no idea!

Thanks again gents.
Posts: 4
Joined: Fri Sep 09, 2016 10:41 am

Re: planning 4" plated, modular, need suggestions.

Postby JayD » Thu Oct 20, 2016 8:52 am

This build is a 3" one piece build the procedure is the same there abouts depending on your skill set and tooling, This build was put forward to demonstrate you do not need a fancy workshop to build one just basic tools. :obscene-drinkingcheers:
Posts: 1535
Joined: Mon May 06, 2013 8:58 pm
Location: Tasmania, home of world class Whiskey...

Re: planning 4" plated, modular, need suggestions.

Postby Swedish Pride » Thu Oct 20, 2016 7:41 pm

JayD wrote:This build is a 3" one piece build the procedure is the same there abouts depending on your skill set and tooling, This build was put forward to demonstrate you do not need a fancy workshop to build one just basic tools. :obscene-drinkingcheers:

What I'm most impressed with in this build is that you use straight snips to cut a curve in the sightglass module, I can just about cut it straight ... :bow-blue:
Don't be a dick
Swedish Pride
Posts: 138
Joined: Wed Oct 01, 2014 6:51 am
Location: Ireland

Return to Plated Columns

  • Who is online

    Users browsing this forum: No registered users and 1 guest