Shotgun Proportions

Anything cooling/condenser related.

Moderator: Site Moderator

StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

Glad to hear it works well..

A question.. what I see from the picture, the condenser is welded to the column piece.. and what is holding the outlet/spout piece to the shotty..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
User avatar
Demy
Master of Distillation
Posts: 3084
Joined: Fri Sep 04, 2020 1:45 pm

Re: Shotgun Proportions

Post by Demy »

Yes, the final part is a spout that can be removed and is telescopic to adapt the length. I thought for a while and then I decided to adopt this system trying to adapt the pieces I had. I use soldering because where I live it is impossible to find tri-clamps, the same goes for large copper pipes.
20210228_114250.jpg
20210228_121209.jpg
StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

So in the eventuality it requires clean, how do you plan cleaning the unit.. and as a starter, say cleaning the flux used in soldering..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
User avatar
Demy
Master of Distillation
Posts: 3084
Joined: Fri Sep 04, 2020 1:45 pm

Re: Shotgun Proportions

Post by Demy »

StillerBoy wrote: Tue Mar 02, 2021 2:35 pm So in the eventuality it requires clean, how do you plan cleaning the unit.. and as a starter, say cleaning the flux used in soldering..

Mars
I cleaned everything possible before welding to the column, then after welding to the column I cleaned and brushed the parts welded through the top and the opening of the glasses, the welds are external in that point. I then cleaned with citric acid and alkaline detergent, rinsed thoroughly and distilled for 2 hours with waste alcohol. I don't think it needs a total disassembly for the ordinary rubbish, from the opening at the top of the column I can see the gun tubes, a little detergent fill the spaces and a little shaking will be enough to clean all the parts. There are forum members who only use water for cleaning.
User avatar
subbrew
Site Donor
Site Donor
Posts: 1275
Joined: Thu Jan 21, 2021 1:40 pm
Location: West of the Mississippi

Re: Shotgun Proportions

Post by subbrew »

StillerBoy wrote: Fri Feb 26, 2021 2:51 pm
Demy wrote: Fri Feb 26, 2021 2:22 pm I deduce that I guessed it, that is, a rifle has other advantageous aspects that interface with the column. After all, my questions weren't totally stupid.
It would make things a lot easier if you could use the right word.. a shotgun condenser is not a rifle..

The statement "other advantageous aspects that interface with the column" is erroneous... a shotgun condenser's only function is to condense vapors and cool down distillate.. it's ability to do such make it superior to a liebig only because of its ability to limit the restriction of the vapors at the point of being condensed..

The shotgun condenser is a very condenser for the following style of stills, namely a flute, a CM and a pot setup.. and the other point that a shotgun condenser has working for itself, it does not have to be all that big and heavy.. a 1 1/2" x 14 - 18" will serve all the needs require at the hobby level..

Mars
Mars - thanks for all the information provided. Tips like cutting the vapor tube ends at an angle to direct the condensate to the center is the sort of thing I never would have thought of.

Still in the planning stages of a build, pot still. The plan is for a three inch column from a keg, reduce to two inches and then a shotgun condenser. Above you mention that 1.5 inch will serve the needs. But are there any advantages in staying with a two inch shotgun? I know I can get an extra tube or two in a two inch. In either case I was planning on about 20 inches long with three or 4 baffles.

My thought process is that a two inch will further reduce vapor velocity which is good. But I will also need to be able to throttle water flow down farther to get a temperature gradient and control distillate temp exiting. I guess my question is can you reduce vapor velocity too much and cause problems.

And a thought on baffle design. I saw yours had holes between the tubes. Can you think of any advantages or disadvantages to cutting 7 or 8 radial slots out from the each tube passage? This would force the water next to the tube and should cause significant turbulence. The slots would have to be short, probably a quarter inch at most.

Thanks,
User avatar
Twisted Brick
Master of Distillation
Posts: 3771
Joined: Sat Mar 09, 2013 4:54 pm
Location: Craigh Na Dun

Re: Shotgun Proportions

Post by Twisted Brick »

subbrew wrote: Thu Mar 18, 2021 7:53 am
Above you mention that 1.5 inch will serve the needs. But are there any advantages in staying with a two inch shotgun? I know I can get an extra tube or two in a two inch. In either case I was planning on about 20 inches long with three or 4 baffles.

My thought process is that a two inch will further reduce vapor velocity which is good. But I will also need to be able to throttle water flow down farther to get a temperature gradient and control distillate temp exiting. I guess my question is can you reduce vapor velocity too much and cause problems.
As I understand it, the ideal total diameter of the vapor tubes should match the diameter of the incoming tube, which would allow for no increase in vapor speed. In the big commercial pot stills, the condensers are a bit different, with the coolant running inside the tubes and the vapor running directly into the shell. There is a bulge in the top of the condenser built to allow the entering vapor to slow down, effectively increasing the condenser's efficiency.

At the hobby scale, this is most likely overkill. I run a still like you are proposing and have considered building a 3" shotgun with 1/2" tubes, but the condenser I already have works perfectly fine. A 20 x 2" shotgun will perform admirably, and installing 4 vapor tubes will allow the incoming vapor to be divided by four, not three, optimizing your shell diameter.
“Always carry a flagon of whiskey in case of snakebite, and furthermore, always carry a small snake.”

- W.C. Fields

My EZ Solder Shotgun
My Steam Rig and Manometer
StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

subbrew wrote: Thu Mar 18, 2021 7:53 am Still in the planning stages of a build, pot still. The plan is for a three inch column from a keg, reduce to two inches and then a shotgun condenser. Above you mention that 1.5 inch will serve the needs. But are there any advantages in staying with a two inch shotgun? I know I can get an extra tube or two in a two inch. In either case I was planning on about 20 inches long with three or 4 baffles.
I don't own a 2" shotgun at the this time, so I cann't really speak on it efficiency vera 1.5".. The experiment runs using the 1.5 x 12" with 5 - 3/8" tubes shotgun, at least the one I'm using, indicates that it very efficiency not just in knock down ability but also in reducing water usage..

The advantage a 2" will have over the 1.5" is the ability to use less water flow to do the same job.. and if it was I building a 2", I would go around 16" in length with 4 baffles, based on was what the 1.5" can knock down.. my view is that the more smaller tubes that can be fitting and with properly built baffles, the higher efficiency the shotgun with be.. and as a shotgun provide better efficiency, there is a time saving in the stripping run..

Also it's best to reduce pipe size to match the condenser size right at the condenser face..
subbrew wrote: Thu Mar 18, 2021 7:53 am And a thought on baffle design. I saw yours had holes between the tubes. Can you think of any advantages or disadvantages to cutting 7 or 8 radial slots out from the each tube passage? This would force the water next to the tube and should cause significant turbulence. The slots would have to be short, probably a quarter inch at most.
My view on baffles is that they are there to restrict water flow, and to guide the water flow.. the holes are there to guide the water flow between the tubes and create some resistance, plus 3 or 4 V notches where the tubes slide through also provides guidance next to the tubes.. a small V notch would be my preference over a slot cutout.. more water flow right next to the tube..

Also remember that a PC condenser does / serve two functions.. it condenses the vapor and cools the distillate..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

Twisted Brick wrote: Thu Mar 18, 2021 11:35 am At the hobby scale, this is most likely overkill. I run a still like you are proposing and have considered building a 3" shotgun with 1/2" tubes, but the condenser I already have works perfectly fine
A 3" shotgun would be an overkill, bit time.. if a 1.5 x 12" on a 2" column setup can knock down 5000w using 1.3L per min of water usage, why would one need a 3".. and the weight would be another issue not required..

One can go only so fast with the stripping runs, and spirit run considerably slower..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
User avatar
subbrew
Site Donor
Site Donor
Posts: 1275
Joined: Thu Jan 21, 2021 1:40 pm
Location: West of the Mississippi

Re: Shotgun Proportions

Post by subbrew »

StillerBoy wrote: Thu Mar 18, 2021 12:31 pm
subbrew wrote: Thu Mar 18, 2021 7:53 am Still in the planning stages of a build, pot still. The plan is for a three inch column from a keg, reduce to two inches and then a shotgun condenser. Above you mention that 1.5 inch will serve the needs. But are there any advantages in staying with a two inch shotgun? I know I can get an extra tube or two in a two inch. In either case I was planning on about 20 inches long with three or 4 baffles.
I don't own a 2" shotgun at the this time, so I cann't really speak on it efficiency vera 1.5".. The experiment runs using the 1.5 x 12" with 5 - 3/8" tubes shotgun, at least the one I'm using, indicates that it very efficiency not just in knock down ability but also in reducing water usage..

The advantage a 2" will have over the 1.5" is the ability to use less water flow to do the same job.. and if it was I building a 2", I would go around 16" in length with 4 baffles, based on was what the 1.5" can knock down.. my view is that the more smaller tubes that can be fitting and with properly built baffles, the higher efficiency the shotgun with be.. and as a shotgun provide better efficiency, there is a time saving in the stripping run..

Also it's best to reduce pipe size to match the condenser size right at the condenser face..
subbrew wrote: Thu Mar 18, 2021 7:53 am And a thought on baffle design. I saw yours had holes between the tubes. Can you think of any advantages or disadvantages to cutting 7 or 8 radial slots out from the each tube passage? This would force the water next to the tube and should cause significant turbulence. The slots would have to be short, probably a quarter inch at most.
My view on baffles is that they are there to restrict water flow, and to guide the water flow.. the holes are there to guide the water flow between the tubes and create some resistance, plus 3 or 4 V notches where the tubes slide through also provides guidance next to the tubes.. a small V notch would be my preference over a slot cutout.. more water flow right next to the tube..

Also remember that a PC condenser does / serve two functions.. it condenses the vapor and cools the distillate..

Mars
Wish I had the time to build two, one with slots and one with V notches. I think the slots would provide more turbulence and be better at disrupting laminar flow, while the V notch might be better at ensuring water flow along the tubes. I started my career as a nuke engineer have done more than a little study of heat transfer. Disrupting laminar flow was a big thing. Nucleate boiling as actually encouraged at the rod/water interface as it disrupted laminar flow. But the drawback is it usually happened at a slight imperfection on the rod surface and could, over time, cause pitting at that imperfection. but I digress.

Once again, thanks for sharing all the info.
StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

subbrew wrote: Thu Mar 18, 2021 2:03 pm I think the slots would provide more turbulence and be better at disrupting laminar flow, while the V notch might be better at ensuring water flow along the tubes.
Both will work.. at least much better than the other method using alternate opening, which in turn create hot spots area..

I'm of the view that it's the smaller tubes along with the number of baffles themselves that improve the efficiency of the shotgun.. spaces every 2 - 2.5" apart would seem the best.. similarly smaller tubes improve the ability to condensed the vapors.. 5 tubes is more efficient than 4 tubes in my view and so on.. they are just a little more work to making them.. may just play around with making a 3/8 x 12" x 2" one some days, just to see now that the bug as bit me..

The 1.5 x 12" was built a few yrs back for my 3" flute.. and never thought much of using it to strip with, until recently.. I was amazed how little water was needed, plus saving in time also.. I recently built a 2" goose neck all the way to the condenser face.. saving over 15 min per 30L strip runs.. almost an hour over 3 runs over using a 26" liebig with 3000w..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
User avatar
subbrew
Site Donor
Site Donor
Posts: 1275
Joined: Thu Jan 21, 2021 1:40 pm
Location: West of the Mississippi

Re: Shotgun Proportions

Post by subbrew »

StillerBoy wrote: Thu Mar 18, 2021 4:27 pm

The 1.5 x 12" was built a few yrs back for my 3" flute.. and never thought much of using it to strip with, until recently.. I was amazed how little water was needed, plus saving in time also.. I recently built a 2" goose neck all the way to the condenser face.. saving over 15 min per 30L strip runs.. almost an hour over 3 runs over using a 26" liebig with 3000w..

Mars
You have me excited to get on with my build. My present system I bought from a friend. The column is https://www.essentialdistilling.com/com ... -II-Column As you can see it is a very small SS liebig. Very easy to overpower. 6 gal stripping run is about 5 hrs. Much above a quart and hour will over power.
VerticalEaz
Novice
Posts: 7
Joined: Wed Mar 17, 2021 6:42 am
Location: Cape Town, South Africa

Re: Shotgun Proportions

Post by VerticalEaz »

Hi Guys, Newbie here.

I hope that I am posting in the correct thread. I am in the process of building a CCVM still - 50 liter converted keg style. Plan on using 2x 2kW geyser elements in the boiler, all stainless steel since I have access to a professional welder at work.

I plan on building a shotgun condenser with 4x 12mm diameter by 1mm thickness SS tubes in a 2" SS pipe. I was also thinking that I can use my pool water to circulate through the condenser (25 000 liter pool, average temp 25 deg C). I understand one can go about this very scientifically but to me that seems rather daunting so I am hoping to get an answer from someone with a lot of experience that is considered "safe". How long should my condenser be? Let's assume a pump that does 40 liters per minute (also open to upgrading pump specs if the recommended condenser length is ridiculous).
Some mornings it's just not worth chewing through the leather straps.
StillerBoy
Master of Distillation
Posts: 3387
Joined: Thu Dec 01, 2016 6:27 pm
Location: Ontario

Re: Shotgun Proportions

Post by StillerBoy »

VerticalEaz wrote: Fri Apr 09, 2021 12:39 am How long should my condenser be? Let's assume a pump that does 40 liters per minute (also open to upgrading pump specs if the recommended condenser length is ridiculous).
As to the shotgun length, anywhere in the range of 20 - 24" will do the job..

One note on ss material as a condenser, it's not the recommended material as will not dissipate the heat well as copper will, and will require more water flow.

As to using water from your pool, it has been done before.. also it's not so much the distance that has to be a concern, but the height that the pump can push up.. off hand, you will need one that can push at least 10 - 12 ft in height..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

– Albert Einstein
User avatar
Berserk
Bootlegger
Posts: 125
Joined: Wed Jan 18, 2017 7:22 am
Location: The chilly north

Re: Shotgun Proportions

Post by Berserk »

Hey Vertical,

If the tubes are 12mm outer diameter you can fit 7 of them in a 2" shell. You'll have a wider vapor path and a larger cooling area, which will make the shotgun more efficient :)

If it's 12mm inner diameter then 4x of them is a common configuration of shotguns on the forum, 20-24" long as Mars said, so that should probably work out fine!
Cheers,
Berserk

He who stumbles around in darkness with a stick is blind.
But he who sticks out in darkness is fluorescent!
VerticalEaz
Novice
Posts: 7
Joined: Wed Mar 17, 2021 6:42 am
Location: Cape Town, South Africa

Re: Shotgun Proportions

Post by VerticalEaz »

StillerBoy wrote: Fri Apr 09, 2021 7:14 am
VerticalEaz wrote: Fri Apr 09, 2021 12:39 am How long should my condenser be? Let's assume a pump that does 40 liters per minute (also open to upgrading pump specs if the recommended condenser length is ridiculous).
As to the shotgun length, anywhere in the range of 20 - 24" will do the job..

One note on ss material as a condenser, it's not the recommended material as will not dissipate the heat well as copper will, and will require more water flow.

As to using water from your pool, it has been done before.. also it's not so much the distance that has to be a concern, but the height that the pump can push up.. off hand, you will need one that can push at least 10 - 12 ft in height..

Mars
Thanks Mars. Yeah I get that copper has the advantage in dissipating heat (from what I read the thermal conductivity is around 7x that of SS) but for me SS has the advantage in cleaning, price and again, I would rather let a professional welder build the still for me than me having to learn how to braise.

Just to be sure, the 20-24" condenser length is taking a SS condenser into consideration?

Does anyone with converted keg experience know how much weight the 2" ferules and tri-clovers clamps can hold? I can always go overkill with the condenser but I am not really sure how strong those clamps are and a long condenser filled with water and pipes hanging off it can be heavy.
Some mornings it's just not worth chewing through the leather straps.
User avatar
RC Al
Swill Maker
Posts: 434
Joined: Sun Feb 11, 2018 12:40 am
Location: Sunny Queensland Oz

Re: Shotgun Proportions

Post by RC Al »

Provided they are attached decently to the tube, well and truly more than enough (100's of lbs). That said it dosent hurt to have strain relief for the ease of assembly, take down and life/integrety of the gaskets. Gantry, braces, wall clamps, roof wires/chains will all help, have a search.
Post Reply