School Me On My Design

[Azures]

Hi,

I am a new member and this is my first post.
I'm thinking about making a still from modifying a Bokakob design.

The Inner Tube (2.5") channels the vapour into the Spiral Passage. The Cooling Tubes (1/4") are soldered to the Inner Tube and tight up against the Outer Tuber (3"). The Vapour helixes up the Tower, while reflux runs down. The helix passage is long so the reflux and vapour have allot of distance to interact. Distillate from the condenser can be refluxed back into the top of the tower and run back down.

The Inner Tube with soldered Cooling tubes will be squeezed and squished slightly into the Outer Tube.

My questions are:

1) How long should the Tower be, up to the bottom of the Inner Tube & Cooling Helix? (Cost and Size issues)
2) How long should the Inner Tube & Cooling Helix be? (Too long the distillate may never come out)
3) Distance between cooling tubes on the Helix? (Too small reflux could bubble and block Vapour, to big and not enough interaction or cooling)
4) Should I not bother and just keep it simple and stick with Bokakob design? (The soldering of the Cooling tubes will be a pain in the ass, but the idea is for it to be air tight so vapour has to helix up the tower, taking a long path.)

All thoughts are welcome, school me!

[NcHooch]

I sorta like the theory, but I think the design is very impractical from a building point of view, it'll be next to impossible to control the cross section width of the 1/4" cooling tube as you wind it around the inner tube (it's gonna flatten out), which will result in lots of leaks in the helix coolin passages. ....and I don't think you will be seeing any reflux (re-evaporation) in those passageways, only condensing. Where exactly is the distillate coming out?

I must be missin something.

NChooch

[Bushman]

I agree the pictures are nice but something is missing. As far as answering one of your questions most people here make the reflux column 48". The design seems a little complicated.

[rad14701]

No need over-complicating the simple Bokakob design, Azures... One issue I see is that with the spacer tube down the center you would be causing a vapor speed increase up past the reflux condenser... If the fit is tight then you could end up with flooding... Letting the entire volume of the condenser head get cooled would be more efficient... Perhaps using a scrubber would work better...

The simple Bokakob dual slant plate LM reflux column is a prime example of the KISS concept which has proven to work quite well in spite of its simplicity...

[myles]

Folks have been playing with spiral vapour paths for a long time. I am doing one myself right now, BUT they are far from easy. Keep it and save it for later when you have tried some more easy to run and build designs.

Nice concept but not a good one to start with. There are lots of nice designs out there. Do NOT start building too soon would be my advice as there are so many variables. I don't like the "1 still suits all idea " either, so make sure you are clear on what you want as an outcome.

Its better to build a good still to do what you want, instead of a general do it all compromise. You didn't even mention what sort of product you wish to make. It DOES make a difference to your choice of design.

[Azures]

width of the 1/4" cooling tube as you wind it around the inner tube (it's gonna flatten out)

I was thinking depending on how much it flattens out I could use a 3" outer pipe with a smaller Bore.

[Azures]

I don't think you will be seeing any reflux (re-evaporation) in those passageways, only condensing. Where exactly is the distillate coming out?

I was worried about the re-evaporation in the passage way. I was hoping as the condensate ran down the helix, it would be heated by the hotter vapours rising up, which gets hotter the further down the helix the distillate goes. Eventually absorbing enough energy to re-evaporate, while the vapours giving off heat to the distillate and cooling tubes will start to loose energy and condense. an almost crazy equilibrium.

Some of the vapour should get to the top of the helix and exist threw the green pipe next to the thermometer and into the condenser, either it all goes to a jug or some of it gets returned back into the helix threw the purple whole at the top.

[Azures]

One issue I see is that with the spacer tube down the center you would be causing a vapor speed increase up past the reflux condenser... If the fit is tight then you could end up with flooding... Letting the entire volume of the condenser head get cooled would be more efficient... Perhaps using a scrubber would work better...

The simple Bokakob dual slant plate LM reflux column is a prime example of the KISS concept which has proven to work quite well in spite of its simplicity...

Yes the bottle necking with pressure from behind would increase the vapour speed threw the helix, but provided the helix is long enough I thought the vapours would contract in volume and slow down higher up in the helix. Thats why I asked question (2) how long the helix should be.

The flooding would be an issue too thats why I asked questions (3) what should the distance between the coils be? to close I'll get flooding.

[Azures]

Do NOT start building too soon would be my advice as there are so many variables. I don't like the "1 still suits all idea " either, so make sure you are clear on what you want as an outcome.

Its better to build a good still to do what you want, instead of a general do it all compromise. You didn't even mention what sort of product you wish to make. It DOES make a difference to your choice of design.

My Outcome is to get drunk!

I'm thinking about making clear spirit from shop bought yeast & sugar. (Don't all yell at once!) It was my understanding that for making rums & whiskeys requires a pot still and someones grandpaps recipes for the mash to get the flavour. That all seems like to many points of failure for a first attempt, that could taste fowl!

So I thought plain simple clear spirit to start with.

What would you suggest?
I have one suggestion for Bokakob dual slant plate LM reflux column.

[Azures]

I'd like to thank you all for your replies. If you like to reply to what I've continued from your responses that would be great.

The general unanimous response is "Its very tricky" & "Don't do it for first attempt"

So I won't.

Any suggestions for what I should do for a first attempt, at making clear spirit?

[Azures]

The simple Bokakob dual slant plate LM reflux column is a prime example of the KISS concept which has proven to work quite well in spite of its simplicity...

what does LM mean?

Is this the design your talking about? http://homedistiller.org/image/drawing_ ... e_EL-2.jpg

Also does this bubbling plate design -> http://homedistiller.org/image/drawing_ ... tes_SP.jpg
replace the packing an empty column with wire wool?

[rad14701]

LM stands for Liquid Management...

There is plenty of good information in the New distiller reading Lounge...

While you are in there you should definitely check out:

Basic Overview of Common Reflux Designs

And

VM, CM, and LM confusion

But don't stop there as there is a wealth of great information in there...

[Azures]

Outstanding! I think VM it is!

[Braz]

Outstanding! I think VM it is!

Aren't you glad you stopped by?

[Prairiepiss]

Interesting CM design. I'm going to guess as I am a nube. The vapor passage would be very small (possible flooding as noted earlier). With the vapor path that small it would be very hard to control the coolant flow to get product output if it didn't flood.

I think you made a wise choice to look into a Bokakob slant plate VM.

[Azures]

very hard to control the coolant flow to get product output if it didn't flood.

Yeah thats what I was thinking.
It does seem to be a CM which I now feel is the worst management.

[myles]

very hard to control the coolant flow to get product output if it didn't flood.

Yeah thats what I was thinking.
It does seem to be a CM which I now feel is the worst management.

I have to take issue with you on this. CM is without doubt the best management system for heads compression. It is also a real PITA if you try to use it for the entire run, as it needs constant tweaking and attention. Combining CM and VM is an outstanding solution.

If you include Power Management and fine control of your coolant flow rates, you have a very versatile setup.

http://homedistiller.org/forum/viewtopi ... 7&hilit=CM

Control of your coolant flow rates is a key issue. During the hearts phase of your run you should aim for a warm coolant output - your coolant output temperature should be 80 - 85 degC.

Power Management combined with CM and a short heads column( during the early stages), over a standard VM column works for me. It may not suit others but there are so many systems that will work, it is a case of combining the features that YOU want.

OK I am PICKY and like to include a condenser in my vent line ( also used as my heads condenser), but if you ignore that, what I run is simply a horizontal coil (alternative to a shotgun condenser) over a short heads column, that is mounted over a basic VM column. Combined with a power controller it works just fine.

[Azures]

I was thinking about 2" VM or a LM/VM hybrid.

I was looking at the LM part to take heads off as some others have done it. Not sure why you can't just use the VM to take heads off. Is it because 50% heads vapour returns to the reflux using VM, with a 1:1 ratio. so trying to get all heads out is slow.

I was worried that the LM pool may have a little stagnant heads sitting there, but do you just open it up full, empty it out all heads gone then, switch to VM for hearts?

is VM/LM hybrid good?

CM / PM seems to be very easy to add.

All I need is the water supply on MAX with a thumb screw on the output and I then have CM correct?

for heating I am gonna use an electric tea urn / water boiler, All i'd need is to have thermostat from the water boiler set at a position of interest at a value of interest and then I've got PM.

so potentially I build VM/LM hybrid, still

then add the CM and PM functionality to it.

would that give me a VM/LM/CM/PM hybrid?

[aqua vitae]

Harry hasa design some kind of LM/VM hybrid that he and others claim to work good for concentrating heads. Don't know if it's a thread about such build at this forum?

Myles have a VM/CM hybrid that looks like a spaceship (no harm intended, he is an awesome copper craftsman).
Remember that a CM can't be ventilated at the top as the LM and VM designs. You could add a valve or cap of some sort to shut the ventilation, but be aware, this is dangerous grounds as if you forget it shut and runs it as a VM you'll get a pretty awesome explosion.

[Manback]

The VM and LM in Harry's design is to avoid contamination of the VM arm, I think. It's not really a trap, more works off the theory of continuous bleeding while maintaning equilibrium.. I think that's the theory, anyways..

With regards to slow take-off during heads - if you're bleeding them you want to be running pretty high reflux.. definitely over 50%.. so that's not it, good thinkin' though

[Azures]

CM can't be ventilated at the top ...... if you forget it shut and runs it as a VM you'll get a pretty awesome explosion.

Okay so I can't be bothered with CM.

[Azures]

The VM and LM in Harry's design is to avoid contamination of the VM arm, I think.

So none of the heads goes into the VM arm, so hearts taken from VM is cleaner.

Is head removable the only reason to add LM to VM.
Is Contamination in the VM really a problem?

I have an intended VM build. which I may document and make a second diary thread.

I really want people to tell me if I should add LM to the VM? is it worth it? do I gain? shall I bother?

would really like a sort definitive answer (not gonna happen I know)

[aqua vitae]

I can't give a definitive answer but I can tell you how I would have done if I was you.
I would have built a VM without LM option. And placed the valve horizontal so you can shut it without risk of pooling.

[Azures]

I can't give a definitive answer but I can tell you how I would have done if I was you.
I would have built a VM without LM option. And placed the valve horizontal so you can shut it without risk of pooling.

Yep horizontal valve is what i am going to do, you you recon don't bother with LM.

I understand that i can always open up the pipe and add LM above the Tee and below the condenser... but if its worth doing later then I should just do it now.

at the moment I can't really see much of an advantage added LM compared to the effort.

[Azures]

I've decided that I am going to make pure VM.

I'll try and start a traditional coil this weekend, after I buy some Gas to re-anneal.

[Azures]

Check out my first Coil and the three different techniques I used Salt, Ice and Nothing

http://homedistiller.org/forum/viewtopi ... 15&t=19854