Bokakob 2" mini-still column

[jake22si]

I got it figured out, thanks

[Elrospo]

made a short column and condenser for striping, will also try them as a pot still in the near future.

2" copper pipe with 2" treaded female copper fitting for the column.

1/2" copper pipe
2x 1/2" copper end cap
3/8 copper pipe
1/4" copper pipe

drilled 1/4" hole on the end caps and 3/8" holes on the 1/2" pipe.
was easy to make took me like 15min.

shortcolunmandliebig.jpg

I wanted to ask a "thing" in this type of distillation column comes from the already liquid product,
It comes out hot but liquid product, right ?,
and it flows into the copper pipe to go towards the container hydrometer, and you still will cool more, right?
then the condenser on 'liquid outlet and necessary?
and why?
and that brings benefits?

[der wo]

It's up to you if you cool the product down further. It's not necessary. But without cooling a bit will evaporate, and the alcoholmeter will not give a good measurement, becaus it is calibrated to a certain temp like 20°C for example.

The longer the tube after the valve, the more it cools by itself. But something like a room tempproduct you only get with for example a liebig condenser instead of the tube.

[Elrospo]

ok,
tanks

[cdd]

whats the optimum column length for bokabob with 2kw boiler and 54mm tube?

[zapata]

There is no blanket optimum. A foot might do for some wanting higher proof flavored spirits. 4-5 feet if you want the truest of neutrals (in that case probably drop your power down to about 1800 watts too).
Also depends on packing, e.g. spp can use much shorter columns for the same result.
So what's your packing, and what's your goal?

[cdd]

I will build a minimum size column first and then tri-clamp it taller.

[Yummyrum]

Stripping your wash in a pot still first will result n a significantly better result as far as purity goes if a clean product is what you are after . You can strip the hell out of your wash really fast if you have a lot of power available ( gas burners are great for this ) and it will save you hours of drip drip drip that you would need to do to get the same purity from refluxing straight wash .

I run stripped wash at around 30% abv though 1 meter ( 3 1/2foot ) of 2" ( OD not ID Aussie copper so slightly smaller than yours ) on 2.2kW and that will give me nice clean 95%+ at over 1.2 liters an hour .

[cdd]

has anyone used a shotgun condenser for reflux instead of graham?

[pfshine]

Yes. There is a few threads about that around here. That being said there really is no reason to do it. The coil is easy to build and more efficient for this imo.

[Pikey]

has anyone used a shotgun condenser for reflux instead of graham?

Sorry to be pedantic but that is a "Coil condenser" or if there is a twin spiral a "Dimroth" (coolant flows through coil - with a Graham, the distillate goes through the coil)

[Budapest8485]

I'm still not clear on what the center tab does on the slant. The liquid will fall off the top slant onto the bottom one regardless if there's an overlap. What am I missing?

[Expat]

The tab provides a focus for the drip to form as it goes over the edge, Directs the reflux to the middle of the column where it is most effective.

[Budapest8485]

The tab provides a focus for the drip to form as it goes over the edge, Directs the reflux to the middle of the column where it is most effective.

Okay, I'll include it. Thanks for the added explanation.

[WithOrWithoutU2]

I've planned to make a 2" boka head out of Type M copper with a tri clamp ferrule to connect to my stainless steel 36 in column. My guess is the head will be about 12" to 18" in total length. I planned to use 1/4 soft refrigeration tubing on the take off and connect to a lead free brass needle valve. I wasn't going to connect to a condenser, but seems like many recommend it. I think I can make a simple lieberg (12" of 3/4 tube with the 1/4 take off tubing running through it). Being so inexperienced at soldering, I am really concerned about all the weight that will be on the 1/4 soft refrigeration tubing. For one, I am not sure the solder joint will hold at the connect point. Second I am not sure this 1/4 tubing can hold the weight without bending and thus kinking. The head will likely be to small to fashion some sort of support connection it.

So I guess my question is will a soldered 1/4" refrigeration tubing hold the weight of a condenser and not be easily damaged when moving /storing the head? What have others done to minimize this type of risk?

Thanks

[NZChris]

I'm not quite sure what you mean, but my column is slung from the roof by chains and turnbuckles attached to the top of the Bokakob head, not to the reflux condenser. That condenser sits free in the head and is connected to flexible hoses.

[Tummydoc]

He's referring to adding a product condenser, not the reflux condenser. I dont run a boka. A product condenser would cool the take off, but doesn't seem necessary for a boka

[NZChris]

Now I get it, I hope.

The product condenser can be tiny and light as it doesn't do much work. Mine isn't, as it has been re-purposed from another distiller's junk pile and I haven't gotten around to building another one.

Have a large footprint for the solder joint and you should be ok.

[Expat]

I've planned to make a 2" boka head out of Type M copper with a tri clamp ferrule to connect to my stainless steel 36 in column. My guess is the head will be about 12" to 18" in total length. I planned to use 1/4 soft refrigeration tubing on the take off and connect to a lead free brass needle valve. I wasn't going to connect to a condenser, but seems like many recommend it. I think I can make a simple lieberg (12" of 3/4 tube with the 1/4 take off tubing running through it). Being so inexperienced at soldering, I am really concerned about all the weight that will be on the 1/4 soft refrigeration tubing. For one, I am not sure the solder joint will hold at the connect point. Second I am not sure this 1/4 tubing can hold the weight without bending and thus kinking. The head will likely be to small to fashion some sort of support connection it.

So I guess my question is will a soldered 1/4" refrigeration tubing hold the weight of a condenser and not be easily damaged when moving /storing the head? What have others done to minimize this type of risk?

Thanks

Short answer is yes it will hold the weight of a small PC but it will be easy as hell to damage it as 1/4" has basically no strength. A knock or a drop and you're resoldering the piece. With my 2" I later switched up to 3/8" which helped but it ended up being replaced again due to damage. The basic nature of soft tube doesn't lend itself well to many breakdowns and rebuilds.

In my most recent build (3" bok) I decided to move to 1/2" hard tube for the takeoff. I soldered a male threaded coupling directly as the takeoff and threaded the valve into that. PC is 3/4" / 1/2" (overkill salvaged from another project) which is connected to the downstream side of the valve by small triclamp.

Can post a pic if you're interested.

[WithOrWithoutU2]

I've planned to make a 2" boka head out of Type M copper with a tri clamp ferrule to connect to my stainless steel 36 in column. My guess is the head will be about 12" to 18" in total length. I planned to use 1/4 soft refrigeration tubing on the take off and connect to a lead free brass needle valve. I wasn't going to connect to a condenser, but seems like many recommend it. I think I can make a simple lieberg (12" of 3/4 tube with the 1/4 take off tubing running through it). Being so inexperienced at soldering, I am really concerned about all the weight that will be on the 1/4 soft refrigeration tubing. For one, I am not sure the solder joint will hold at the connect point. Second I am not sure this 1/4 tubing can hold the weight without bending and thus kinking. The head will likely be to small to fashion some sort of support connection it.

So I guess my question is will a soldered 1/4" refrigeration tubing hold the weight of a condenser and not be easily damaged when moving /storing the head? What have others done to minimize this type of risk?

Thanks

Short answer is yes it will hold the weight of a small PC but it will be easy as hell to damage it as 1/4" has basically no strength. A knock or a drop and you're resoldering the piece. With my 2" I later switched up to 3/8" which helped but it ended up being replaced again due to damage. The basic nature of soft tube doesn't lend itself well to many breakdowns and rebuilds.

In my most recent build (3" bok) I decided to move to 1/2" hard tube for the takeoff. I soldered a male threaded coupling directly as the takeoff and threaded the valve into that. PC is 3/4" / 1/2" (overkill salvaged from another project) which is connected to the downstream side of the valve by small triclamp.

Can post a pic if you're interested.

Expat,

Thanks for the answer. I think I will move forward with making the 2" as I have the coil and all the part. But I will likely not put a product condenser on it and see if I loose much to evaporation from the hot product coming off. I'll treat the 2" as kind of a practice column (building and using). Then I will move onto making a 3". So if you would post pics, instructions and details parts list for the PC part I would appreciate it. I am finding myself running back and forth to the hardware store or ordering online as sometimes the parts listed on these projects assume you know at least a little about plumbing fixtures, sizing and what it really takes to connect them. Well I knew absolutely nothing when I went shopping for parts and tools. And I still know next to nothing. The sizing (ID, OD, Nominal, etc), fitting types, connection types, thread types, and what works with what has cause me to waste both money and time as I go. And all I've actually done so far built a parrot, made a coil winding jig, and wound a coil condenser. But as someonme who has never really "worked with my hands", I must say building what little I have has given me so much pleasure and sense of fullfilment. I can only imagine what it will be like once I have a functioning column that I built myself.

[Expat]

I think that parts and instructions have been pretty thoroughly discussed for the Bok build so I won't repeat them here.

As far as I'm aware the only difference between my approach and the standard is the use of a 1/2" male threaded directly as the takeoff (no tube) and into the female threaded of the needle valve.

Fully assembled:

Bok head only:

[Cletus_Spuckler]

WithOrWithoutU2; regarding the strength of a 1/4" take off question; bare in mind that annealed copper goes fairly strong once its work hardened. Ie; every time you bend it, straighten it, polish it etc, it gets harder. If the copper you're working with is cold drawn (not annealed), it should be hard enough.

For a boka, the size of take off tube is not really important, it's more about minimum flow rate of your valve. You want something that you can dial in with very fine control, flow rates as low as say 1ml p/minute for spirit runs; and then open up to 50ml (or higher) p/minute for stripping runs.

Valves with low flow rates tend to be found on those with smaller diameter tube connections, such as 1/4" or 3/8". You may even be able to find a valve which operates to your liking with a 1/2" tube connection.

A 1/4" takeoff tube will limit higher flow rates. For this reason, I went with a 3/8" take off for my 2" and 4" boka, with no complaints. A 3/8" tube will not restrict liquid flow, even on stripping runs. I've found the 3/8" take off is also strong enough, provided you also provide some kind of stand or bracket to support the liebig.

Regarding the need for a liebig, I would advise getting one. They bring your product temp down to what you need to take a alchometer readings and makes it easier to handle in general.

[WithOrWithoutU2]

take off.jpg

WithOrWithoutU2; regarding the strength of a 1/4" take off question; bare in mind that annealed copper goes fairly strong once its work hardened. Ie; every time you bend it, straighten it, polish it etc, it gets harder. If the copper you're working with is cold drawn (not annealed), it should be hard enough.

For a boka, the size of take off tube is not really important, it's more about minimum flow rate of your valve. You want something that you can dial in with very fine control, flow rates as low as say 1ml p/minute for spirit runs; and then open up to 50ml (or higher) p/minute for stripping runs.

Valves with low flow rates tend to be found on those with smaller diameter tube connections, such as 1/4" or 3/8". You may even be able to find a valve which operates to your liking with a 1/2" tube connection.

A 1/4" takeoff tube will limit higher flow rates. For this reason, I went with a 3/8" take off for my 2" and 4" boka, with no complaints. A 3/8" tube will not restrict liquid flow, even on stripping runs. I've found the 3/8" take off is also strong enough, provided you also provide some kind of stand or bracket to support the liebig.

Regarding the need for a liebig, I would advise getting one. They bring your product temp down to what you need to take a alchometer readings and makes it easier to handle in general.

Thanks for the advice.

[WithOrWithoutU2]

I think that parts and instructions have been pretty thoroughly discussed for the Bok build so I won't repeat them here.

As far as I'm aware the only difference between my approach and the standard is the use of a 1/2" male threaded directly as the takeoff (no tube) and into the female threaded of the needle valve.

Fully assembled:
rps20190827_192351.jpg

Bok head only:rps20190827_195208.jpg

I really like how modular you made the head. The ability to add glass above and below the colection portion is definately something I would be interested is doing as I think actaully observing what is happening would be both informative and very cool to watch.

[Expat]

I think that parts and instructions have been pretty thoroughly discussed for the Bok build so I won't repeat them here.

As far as I'm aware the only difference between my approach and the standard is the use of a 1/2" male threaded directly as the takeoff (no tube) and into the female threaded of the needle valve.

Fully assembled:
rps20190827_192351.jpg

Bok head only:rps20190827_195208.jpg

I really like how modular you made the head. The ability to add glass above and below the colection portion is definately something I would be interested is doing as I think actaully observing what is happening would be both informative and very cool to watch.

Yeah, through several rebuilds over the years I pushed to maximum modular.

Being able to move the glass around is helpful. Actually I ended up using with my pot setup also. I.e. Boiler--> Glass --> Bok head --> pot riser

A few things that I like: simple place to measure vapor temp as I would for bok operation. Adds turbulence to the vapor stream. Acts as a catch for any passive reflux which would otherwise drop into the boiler.

Regardless of the design you end up building, ensure that the distance between the slant plate and valve is as small as possible, so as to reduce smearing.

[WithOrWithoutU2]

Well, I got the boka head done. It is ugly as heck, but it has past the water test with no leaks. Tomorrow, the vinegar run and Monday I will run some fients through it.

This is the first thing I have ever built like this. I had to spend more on tools than if I bought a boka head. But now I have the tools and the experience. I must say this has been fun and rewarding. I appreciate all the help.

The soldering by far was the most challenging. I read as much as I could, cleaned the parts, plenty of flux, had a lip on the plates, and heating up slow from 2 to 3 inched away. But I just could not get the solder to flow and STICK in the gaps. The solder would fill most spots but a couple gaps just would not fill. I recleaned, refluxed and nothing seemed to help. I did read liquid flux may have been better for this than the paste I have. I have "tinning" paste so I wonder if that was bad. It was suppose to help by getting the surface started with the powdered solder etching in during heat up. I don't think the gaps were huge but have nothing to compare it to. After trying twice (cut new head and plates) I finally just said screw it and started melting the solder in the flame directly and literally globbed it in the gaps. I end up globbing the hell on most of it. I let it cool, then reheated to sort of bake it by getting to liquid state and backed off right away. Like I said it was UGLY,. But I took my Dremel and started grinding away to clean it up the best I can. Still ugly but it is ok and I think it will work. We shall see.

Thanks again to all those that have contributed over the years. Your post of *trials, errors and sucesses" have helped.

I'll let you all know how the cleaning runs go and once I do a real run of some of my Shady Sugar Shine low wines, I will let you all know as well.

[WithOrWithoutU2]

[/quote]

Yeah, through several rebuilds over the years I pushed to maximum modular.

[/quote]

I started thinking about how I could do the lieberg and make it modular. I put a 90 degree angle right off the product take off to lessen the chance of damage. I figure I can create the lieberg with 1/4 tubing running through 3/4 tube. Place caps on it, drill holes, run the 1/4 tubing through it. Then place compression connectors on the ends. I could simply disassemble at the compression connectors after runs to store everything. 1/4 tubing and Compression sleeves are cheap to replace each time.

[Expat]

This is the first thing I have ever built like this. I had to spend more on tools than if I bought a boka head. But now I have the tools and the experience. I must say this has been fun and rewarding.

this is on of the major pleasure imo.

I figure I can create the lieberg with 1/4 tubing running through 3/4 tube. Place caps on it, drill holes, run the 1/4 tubing through it.

3/4 is definitely too large over 1/4. The result won't be all that efficient. Consider 1/2. Cheaper on the material.

[WithOrWithoutU2]

I figure I can create the lieberg with 1/4 tubing running through 3/4 tube. Place caps on it, drill holes, run the 1/4 tubing through it.

3/4 is definitely too large over 1/4. The result won't be all that efficient. Consider 1/2. Cheaper on the material.

Are you saying 1/2 is actually more efficient at cooling a 1/4 tube? I have the 3/4 already, but would get the 1/2 it it would be more efficient.

[Expat]

I figure I can create the lieberg with 1/4 tubing running through 3/4 tube. Place caps on it, drill holes, run the 1/4 tubing through it.

3/4 is definitely too large over 1/4. The result won't be all that efficient. Consider 1/2. Cheaper on the material.

Are you saying 1/2 is actually more efficient at cooling a 1/4 tube? I have the 3/4 already, but would get the 1/2 it it would be more efficient.

Yes.

The goal is to maximize the flow of cool water against the surface of the inner tube and delay it's departure so it picks up lots of heat. Given the opportunity, water flow in the cooler will be though the area of least resistance i.e the center and avoid the drag of a surfaces, where you want it. An optimal cooler would force the water flow to stay directly on the surface of the inner tube, and introduce as much turbulence as possible to slow it's passage, even under pressure.

A 1/4" gap is commonly discussed as optimal due to assembly and material tolerance reasons. 1" over 1/2" has similar considerations to what you have planned.

For additional turbulence, many people including me will spiral wrap a piece copper against the outside of the inner tube, and solder in place. This both increases surface area and turbulence, which ups the efficiency further. Makes for tight fit but works great.

In the end, for a bok a PCs efficiency isn't as critical as a pot still liebig but a cooler product means (as mentioned) less loss and easier hydrometer readings.

Just thinking also, the weight of 1/2" with water will be a lot less than 3/4 and therefore the stress on the take connection will be more manageable.