Multi column taper - hybrid pot

[Mountaintop]

So ... from the title you can see this is a bit of a different sort build. After viewing some older, large scale production pot still photos from Scotland (parent site) I wanted to give it a try. These beauties have a full size capture funnel at the base and slowly taper in a multi-story tower to a small diameter just before the top collection ball and down the condenser column.
This shape would not be easy to produce (then or now) so I assume the craftsmanship in this form must be important to the quality of the final product.

Not sure if this is a column or a pot... My opinion is that all stills are just gradual changes from the basic lab glass experiment to the 40 plate, fuel stills. Is it a pot or a column? Kinda one moving to the other I guess. There will be natural reflux due to the cooling tower effect..put its really just a simple tube on its way to the outlet... So who knows.

Not being a 500 year old copper smith and only having access to hardware store bits, I thought I'd try my downsized (really downsized) design concept that might emulate that big boy and still fit in the kitchen. ...seems to be working well so far.

Materials: old stainless 12 quart stew pot for the boiler, cheap stainless bowl for the lower dome. Copper tube ( nothing bigger than 3/4") adapters, low boy mason jar and a few more copper bits. I also used a bit of cork gasket material and a few ss/ Teflon hoses for the steam heat and cooling water connections.

I was looking for maybe at least 2" base diameter but went with a multiple group of smaller diameters to get a similar area. 6 x 3/4" is where I ended up (3.5"?). This sounded simpler but really meant six times something simpler...which equals out to something hard.

As for the beautiful, Curving taper of that Scottish still.... I went with a more "digital" reduction....reducing the diameters in four steps to get to my six pipe ,tiny diameters at the top. 5 diameter changes in about 32" , starting with 3/4 and ending with1/4 " tubes.

If any one is interested in more info I can post a few photos and more detail.

Top of the mountain to y'all.

[bellybuster]

Hard to picture without pics but I'd suggest that 1/4" is waaaaaaaay too smal to be safe. Maybe I have it wrong??

[rad14701]

Can't visualize what you're describing but it sounds like you're over-complicating things... Ever wonder why that old design is no longer in use...??? Probably due to inefficiency or excessive expense compared to return on investment...

Is this you first still build, by chance...??? Most here would recommend keeping things simple... Sounds like you jumped into the deep end of the pool without your floaties... Good luck...

Pics, please...

[Hound Dog]

Sounds like you jumped into the deep end of the pool without your floaties.....

You have to love the "Radism"!

OP, it really does sound like you are over complicating a very simple process. The design nuances of the huge old stills in Scotland and such don't really carry over to our little hobby stills that well.

[googe]

I think he means a tapered column going up to a onion?, very confusing lol.

[corene1]

If you are wanting to make a tapered column you could get some sheet copper and form it into a taper. Then cut sections and turn them to make the direction changes that you need. That is pretty much what I did. I know it has been said that the shape doesn't change anything at the hobby level but I believe that it made my whiskey a bit lighter and smoother than when I used a short straight column. It might also be that I just want it too make a difference because of all the work that went into it. I went from 4 inch, out to 5 1/2 inches then a long taper down to a 3/4 outlet over the length of 36 inches. One thing for sure is that it is unique.

[Bushman]

One thing for sure is that it is unique.

I would use the word artistic, I also would say that those changes have probably led you to run your still a bit different and thus the combination give you the flavor change you believe has happened.

[Mountaintop]

Bushman called it on the artistic. I was after something that was not typical...but had some bit of "form" following function. A big advantage I think is that although it is only a 2" effective column area, it has the surface cooling of a 5.5" diameter. This means it's effective height is increased substantially over what is geometrically presented. What you don't want is the vapour rising up the middle and missing the cooling sides of the copper. The taper reduction takes care of that by gradually bringing the side walls in to meet the ever diminishing vapour column. The "steps" may even help to keep a turbulent wall flow instead of a laminar interface forming which has less thermal transfer potential and tends to shoot right to the top.

As soon as I figure out how to post a picture I will.

[Mountaintop]

Corene1- exactly.
It's early days for me in this hobby and not much still experience yet so I can in no way relate or equate flavour to still design ...but I'm sure there is something in it. I've only pushed a few gallons though so far but all are very unique in taste and far above my expectation. Can't beat that!

[Mountaintop]

Sounds like you jumped into the deep end of the pool without your floaties.....

You have to love the "Radism"!

OP, it really does sound like you are over complicating a very simple process. The design nuances of the huge old stills in Scotland and such don't really carry over to our little hobby stills that well.

Well...maybe they should.

and..

I always wear my floaties.

[Mountaintop]

First of a few pics..... This is the collection ball at the top.
6 small risers feed into the dome and a single vapour drop tube is in the centre.
The straight tee branch heads to the condenser (through a thermal isolator not shown) and the side tee accepts the digital temperature probe. The ball is removable for cleaning.

I like the transparent aspect because I get to watch vapour condense and drip back down the sides for more reflux. All components are copper, glass and stainless. Large mouth mason gasket makes the vapour tight seal.
More to follow....

[rad14701]

Glass is frowned upon here for safety reasons, whether used for an onion or a thumper or anything else... Looks like the makings of a good bomb...

[Mountaintop]

.. Ever wonder why that old design is no longer in use...??? Probably due to inefficiency or excessive expense compared to return on investment...
e..

Well I disagree..they still are In use today because they work extremely well and produce some of the worlds best whiskey. Scotsmen are frugal to say the least ( and proud of it !) and anything the was not efficient would not have withstood the test of time. All the flavour lives in the shape of the column so I think some divergent from "the norm" is not without merit.

[Mountaintop]

Glass is frowned upon here for safety reasons, whether used for an onion or a thumper or anything else... Looks like the makings of a good bomb...

Sorry for all your frowning. Dude! It's a mason jar, Designed to be filled with 300 degree hot jam by old lady's. A bomb?
I'm running low pressure 200 degree steam...gradually applied. Again... don't agree.

[Tokoroa_Shiner]

Glass is frowned upon here for safety reasons, whether used for an onion or a thumper or anything else... Looks like the makings of a good bomb...

Sorry for all your frowning. Dude! It's a mason jar, Designed to be filled with 300 degree hot jam by old lady's. A bomb?
I'm running low pressure 200 degree steam...gradually applied. Again... don't agree.

I wonder how long this guy lasts before his house is burned down? Lol

You ask some of them old lady's how often they break. Or if they would put the very hot jar on something cold. Everyone here is just trying to keep you safe.

[skow69]

I'd like to see how that is assembled , how the risers fit and where the stepped column comes in.

[Hound Dog]

Not to be negative, but a mason jar is just plain glass, nothing special about its design any more than a beer bottle. It is not borosilicate. As TS pointed out, they break easily during canning and such. I just had one pop apart while pouring in some strawberry syrup I was making to dilute down a batch of SPD. It was just simmering strawberries and sugar water, glad I was over the sink though or it would have been a sticky mess everywhere. .

The glass sections you see in better made column stills like Odin's Istill and such are thick borosilicate that is very strong. These parts are readily available if you search them out.

Let us know how your experiment goes. Don't be offended by good advice. You are on a public forum so everyone has an opinion. Rad knows his stuff. I have gleened a lot from reading his posts.

[googe]

Any chance of a link to the pic on the parent site?, can't see anything like you explain.

[corene1]

I too love to experiment and try different things, but it must be done safely. I have canned 1000's of quarts of jams, jellies, fish and the like and have broken a few jars. Yes it makes quite a mess, but should your jar full of heated alcohol vapors break during a run , that is where the bomb comes in or at least a big fire when it ignites. You ever seen the guys at a race track when they get an alcohol fire? You can't see it but it is devastating. You may make a thousand successful runs with it or it may break on the first one, that is a gamble we don't want you to take.

[Mountaintop]

Ok guys and gals... I get it. thanks for the advice. Acknowledged and appreciated. I know the old mason isn't Pyrex but you also have to remember we are not dealing with high pressure or high temperature as far as thick glass is concerned. As an engineer I can say that it's pretty safe bet. Alcohol does not self ignite on the introduction to atmosphere. It needs flames. This is one of the reasons why I run steam heat. No source of ignition and no chance of burning the goods. These are not high flow or high volume rigs. If you place it on an open fire and plug the downspout ..your on your own- especially with metal-

I'm presenting this here for education and entertainment to all .. not as an indoresment for"what you should do" . Thanks for the warnings and others please take heed to the information and advice advanced by others.

All good. keep the comments coming!
Time for some more photos....

[rad14701]

Any warnings are not intended for your sole enlightenment, they are also intended to dissuade any visitors or other novices from thinking glass is a good idea... To be honest, we don't care if you're an engineer or not... However, as an engineer you should be fully aware that design and implementation should always err on the side of safety...

Don't for one minute think anyone here is picking on you... We are merely attempting to convey the same information here as we would anywhere else in these forums... Perhaps you don't share the same goals in our mission here as the majority here do - that home distillation can be done safely and effectively at the home hobby level by proactively attempting to keep the entire membership as well as visitors as safe as possible... What is gleaned from those efforts depends on each individual...

[Mountaintop]

Rad,
Your point is well taken. I do agree tha safety is first in all endevours.

I understand what your saying but the way you say it makes no friends. "Must be a newbie"..."no floaties in the deep end"
You seem much wiser than those comments portray. I'll chock it up to first impressions never being the best....and be happy to move forward. Again, I appreciate your broader knowledge and look forward to further critique and dilouge.

Best.

[Mountaintop]

As promised, here is a build up of my components.

Here is the boiler. Basically an old 12 quart pot from camping days.
You can see the coil with in and out for steam heat injection. I used 4 draw latches riveted on to pull the top dome down. Next time I would use 6 because the lip is a bit too flexible.

[Mountaintop]

Next, I add a separation lid with a few bubblers to get a semi-plate before the dome. I also added a copper ring to centre the dome and keep most of the vapour away from my external sealing gasket(not shown).

[Mountaintop]

Here is the condenser that rides up the middle of it all. Because I have multiple risers around the edge, the centre is free to place the cooling tube. This keeps the design fairly compact. Basically it's a standard tube in tube with fittings to attach to drain and sink faucet via SS.braided hose. The foam jacket is to eliminate the "sweats." The short worm wiggles below.

[Mountaintop]

Now the fun part. The collection dome with the six risers. These are bolted on with small cork gaskets. Each of the risers are identical and step taper to the next smaller diameter as they rise. The dome is held down with the draw clamps.

[Mountaintop]

And now the whole deal together ready to run. Drop cooler in the middle with hoses attached, multi onion on top feeding and breathing, temp gauge in place but no steam pot attached.

[Mountaintop]

I hope this helps clarify the setup. So far it's been working very well. I have no control on my steam supply so I think I will try a fan blowing across the tubes to increase the heat loss and reduce the net throughput. In ambient air I'm pulling about 200 ml every 5 or 6 minutes. Dropping this a bit would increase the reflux so I'll experiment with that a bit.

Thanks for watching.

[Hound Dog]

Really? I'm looking at the picture but still don't quite understand.

[skow69]

That's a unique rig! I get impressions of art deco, Soviet industrial style, and steampunk.

So it looks like you have 2 plates plus whatever reflux you get in the columns. Do you pack them? What sort of ABV output do you get?

How do you seal the column tops to the risers?

What sort of thermal isolater do you use at the top of the condenser and why?