Going VM/LM or VM/RLM? Which Type of head would you build?

[Rumhead]

Hey you guys!

So i am going to be building my still as I can physically but i can't decide between LM or RLM.

The reason is that I want to be able to do light rums thru the LM part, ie experiment and be able to use it completely like a LM.

Do I loose that ability by going RLM? My thinking says no, but i do need an definiteness in the answer.

Could you please clear this up for me?

After this is answered, ill would like to be able to talk about if slant plate or any other LM is better suited for a combo head, only find ~ 10 yrs old threads about it.


Rikus book is on its way too, maybe get it today

Peace RH

[Yummyrum]

LM , RLM both achieve the same thing . They set a reflux ratio . The product from both will be the same if they both have the same reflux ratio set .

The difference is how the still runs throughout the run .
If you did not adjust a LM , the ABV will drop as the reflux ratio drops through out the run .
If you did not adjust a RLM , it will maintain a higher ABV as the reflux ratio rises throughout the run .

A VM when set to the same reflux ratio as a LM or RLM will also produce the same product . So yes , you can make your light Rum on any of the heads .

I built an LM/VM head with the possibility of RLM . Used LM a couple of times . Switched ti VM and have stayed that way ever since ( apart from converting it to CM for a short time and switching back to VM ) and never bothered with RLM .

I make really nice light Rum , I think it is pretty close to Baccardi , in my VM .

[bluefish_dist]

I built a vm/lm setup and found I rarely used the lm side and eventually just unhooked it. Running purely vm. I always wanted to try rlm as it should run more like a vm in that the reflux ratio increases as the alcohol is depleted, which should require less adjustment to hold a specific abv.

I think the LM style really got its start with the Boka style head which was very common when I started to hang out here 10 ish years ago. Since that time people seem to have moved away from that style and either run a CM based on Chinese built stills or a CCVM due to its ease of construction. Both of those didn’t really exist back then. You could also easily buy copper tube at the big box stores. Now you can’t.

[still_stirrin]

I have a combination LM/VM head for my column. I sometimes use the LM control to compress and collect the heads, while I prefer the stability of the VM valve for the bulk of the run.

The interesting thing about a VM (conventional “valved” control) is that it will hold the %ABV high even as you approach the end of the run. The rate of production will diminish, however, to the point that it stops producing at the backend.

I can collect a little more through the LM valve, but the %ABV at the spout will fall rapidly (the VM manages to strip most of the “goodness” from the boiler).

The VM (conventional valve) is a “set & forget” operation, as the reflux ratio will be managed by the vapor split between the reflux condenser and the product condenser. It is unaffected by the boiler heat input (vapor production rate) or the coolant flow or coolant temperature variations, as long as the reflux condenser can handle the full heat input (adequate knockdown power).

The CCVM can be more sensitive to these fluctuations, so consider that when you’re operating the stillhead.
ss

[Rumhead]

LM , RLM both achieve the same thing . They set a reflux ratio . The product from both will be the same if they both have the same reflux ratio set .

The difference is how the still runs throughout the run .
If you did not adjust a LM , the ABV will drop as the reflux ratio drops through out the run .
If you did not adjust a RLM , it will maintain a higher ABV as the reflux ratio rises throughout the run .

A VM when set to the same reflux ratio as a LM or RLM will also produce the same product . So yes , you can make your light Rum on any of the heads .

I built an LM/VM head with the possibility of RLM . Used LM a couple of times . Switched ti VM and have stayed that way ever since ( apart from converting it to CM for a short time and switching back to VM ) and never bothered with RLM .

I make really nice light Rum , I think it is pretty close to Baccardi , in my VM .

Thanks for your time and help.

I have full understanding of how all still types works and their differences as i have read all the pdf books thats available online so i need no help understanding principles as such, been reading some 1000+ pages and spend about 6 hours a day on the forums that are available mostly here.
Im from a family that has been doing this atleast for 3 generations but there is some evidence that points to it might be all the way back to early 1800. Thats whats is possible to find anyway..

I already distill in a spiral still so i are new to it on my own but i have been around it all my life, so education is covered. But i am fairly new into it and stubborn so i chose to learn on my own, thats the best way.

Yes, Bacardi rum is exactly what prefer and want to make, also fruit spirits like blueberry "vodka type".


Im akso going to be doing a birch spirit, and raspberry, such things from mash not infusion.

Im going to be building a pot column and a pair of strippers.

I will post a log when im thru RIKUs book so you can follow along. Just need to get well and live thru this abcess in my bbrain stem. Might be wheelchair bound for life but i have for now anyway the ability to holdn the flame in left hand and tin in the right hand..

Good night from Karlskrona hospital in Sweden.

[StillerBoy]

As the title of the thread imply, I would go with a LM concentric design, for the following reasons.. easiest to clean if required too as the unit is one straight line, and the unit can be used in hybrid mode..

Mars

[still_stirrin]

As the title of the thread imply, I would go with a LM concentric design, for the following reasons.. easiest to clean if required too as the unit is one straight line, and the unit can be used in hybrid mode..

Mars

+1.

My combination LM/VM head is a concentric design (thanks Rad). It’s an easy build and functions great. I used a 2” x 1-1/2” DWV tee below the concentric throat and the branch is then reduced to 1” for the ball valve (VM). Some use gate valves for the VM and they work great too. I just happened to have the ball valve.
ss

[Rumhead]

Okay concentric it is going to be but i have to decide which of the versions available.

I'm leaning towards slanted plates aka Boka but i would want to hear your opinions on if a "cup" above a thinner part would be better?

The column will be of several parts for maximum modularity with tri clamps.
I'm leaning towards 1*100cm, 1*50cm, 1*70cm column pieces and VM and LM both separated so it is so modular that if I'd like to do a heavier light rum i got many options on packing length.

A pot still head is also in the plan of course.

The idea is to build the most versatile still possible.
And to this one or two strippers.

I do got one thing that might be troublesome, the distance between the VM off take and LM off take and then to the reflux coil.
Are there any restrictions in what works for distance there, can it for example be 40cm between the VM off take and the reflux coil without issues?

My VM tee is 2" and 28mm and my valve is 22mm. The VM Liebig is going to be 22/15mm.
The LM Liebig is going to be 10/12mm and just for getting the temp a tad lower, so maybe only 20cm long.

What do you guys think about it?

[Dancing4dan]

Post a quick sketch

[StillerBoy]

I do got one thing that might be troublesome, the distance between the VM off take and LM off take and then to the reflux coil.
Are there any restrictions in what works for distance there, can it for example be 40cm between the VM off take and the reflux coil without issues?

You have no idea what you are talking about when it comes to a true concentric, and how it's properly built..

A true concentric LM does not use a coil condenser but a jacket cooled condenser, plus the vapor behavior existing the vapor throat body is much different that the boka design..

Mars

Vapour Behavior.jpg

Links to enlighten you on the true conentric..

Originator of the concentric.. viewtopic.php?f=16&t=8046
Rads updated the design... viewtopic.php?t=36382

[Saltbush Bill]

concentric LM does not use a coil condenser but a jacket cooled condenser

Wrong Stillerboy......plenty of LM reflux stills of that design use coil type reflux condensers.

[StillerBoy]

Wrong Stillerboy......plenty of LM reflux stills of that design use coil type reflux condensers.

SB.. why not post the whole phrase, instead of picking and choosing, as you often do..

The whole phrase stated.. "A true concentric LM does not use a coil condenser but a jacket cooled condenser"..

Those that use coil type of condenser are not of the original design and do not work the in the same manner.. and they build a coil one because they do not understand how it is built or they are too lazy to build a proper one..

Mars

[Saltbush Bill]

Define  "A true concentric "......by that do you mean the original design?
Any change on the original is usually an improvement imo.
You only need to look around to see how many of the " jacketed condenser " types are built these days on forums.......about zero in recent times.

You have no idea what you are talking about when it comes to a true concentric, and how it's properly built..

Your rudeness is starting to annoy people again , if you can't be more polite don't post.

[StillerBoy]

Define "A true concentric "......by that do you mean the original design?

Had you taken the time to read the links provided, and not just here and there, as you often do, and instead of using your green jacket, you would have read who was the design the original.. it states the "originator of the concentric".. a member back in 2008..

Any change on the original is usually an improvement imo.

Maybe in your mind and opinion, but not in mind.. again just don't skim but read the whole posting..

You only need to look around to see how many of the " jacketed condenser " types are built these days on forums.......about zero in recent times.

How can you make such a statement.. do you have a crystal ball to state such that member don't build the original style.. I just recently help a member build one, and guiding another one presently.. not discounting the 10 -12 in the past 3 yrs..

Mars

[bunny]

Okay concentric it is going to be but i have to decide which of the versions available.

I'm leaning towards slanted plates aka Boka but i would want to hear your opinions on if a "cup" above a thinner part would be better?

The column will be of several parts for maximum modularity with tri clamps.
I'm leaning towards 1*100cm, 1*50cm, 1*70cm column pieces and VM and LM both separated so it is so modular that if I'd like to do a heavier light rum i got many options on packing length.

A pot still head is also in the plan of course.

The idea is to build the most versatile still possible.
And to this one or two strippers.

I do got one thing that might be troublesome, the distance between the VM off take and LM off take and then to the reflux coil.
Are there any restrictions in what works for distance there, can it for example be 40cm between the VM off take and the reflux coil without issues?

My VM tee is 2" and 28mm and my valve is 22mm. The VM Liebig is going to be 22/15mm.
The LM Liebig is going to be 10/12mm and just for getting the temp a tad lower, so maybe only 20cm long.

What do you guys think about it?

While the above debate continues i would suggest you give consideration to this design:

P1050284.JPG

It's not mine, I wish it was.
My tests show it's not necessary to have the reflux return tube for 2" plumbing.
You can put it in if you like. It won't hurt anything.
Here's a few pics of mine to show just how simple it is to build.

P1050295.JPG

P1050304.JPG

P1050298.JPG

P1050300.JPG

If you're interested, I can probably answer most of you questions about this design and operation.

[StillerBoy]

Here's a few pics of mine to show just how simple it is to build.

Hope you are not encouraging to use the take off method used as it's not an approved design..

Mars

[drmiller100]

Here's a few pics of mine to show just how simple it is to build.

Hope you are not encouraging to use the take off method used as it's not an approved design..

Mars

Approved design??? I've used something similar since 09.

[StillerBoy]

Approved design??? I've used something similar since 09.

The link to the answer..
app.php/rules

Mars

[Twisted Brick]

Approved design??? I've used something similar since 09.

Mars is referring to the plastic spout. You running the same?

[drmiller100]

Approved design??? I've used something similar since 09.

Mars is referring to the plastic spout. You running the same?

Oh. Lol. That isn't a design feature to me. Design is the overall, well, design.
One plastic line isn't design to me.

But yes, that is against the forum rules.

[StillerBoy]

Hope you are not encouraging to use the take off method used as it's not an approved design..

Many here lately just skim through statements and fail to comprehend what is stated..

Design.. A take off using a plastic tube controlled by a scissor clips for managing the removal of hot distillate..

Wiki..

A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process or the result of that plan or specification in the form of a prototype, product, or process.

Mars

[drmiller100]

Hope you are not encouraging to use the take off method used as it's not an approved design..

Many here lately just skim through statements and fail to comprehend what is stated..

Design.. A take off using a plastic tube controlled by a scissor clips for managing the removal of hot distillate..

Wiki..

A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process or the result of that plan or specification in the form of a prototype, product, or process.

Mars

Yes. You are more better than I. I bow to your superior intellect, vast knowledge, and important contribution to this discussion.
Thank you.

May I have another? Please?

[Rumhead]

ä9,Good to see some discussion in the thread.

Im going to go RLM just because the extra reflux control. It also looks better in my eyes.

But i am having decisions about going slant plate or cupped LM...

And please you are all older than me, please act so too?
bickering never ever gives anything positive.
Stillerboy, i do know what a true ccentric is but my native language isnt english so it was more of a short bit of brain freeze. I study distilling all day long all days as i am hosptalised with a abcess in pons in the brain. Extremely rare. My mind is the onlyu part of me thats unaffected. everything else is like your worst drunken time in life plus almost half paralyzed on the left side.
Went thru brain surgery last friday and am steady lie improving and fast so. Got a 11mm new ventilation hole behind my right ear, hopefully effective hot summer days

Plans have changed a bit and im going to go 3" and the parts i already have are going to someone else.

so, for a 3" vm/rlm, what dimension does one go for? Thats where i need your experience right now..

And opinions on which LM solution to use with 3" in mind. Im building for the future as this is such a wast and diverse hobby.
Im reading rikus book too atm so it might evolve to be with heads colon and hammerhead for space saving.

So please continue witth your advices
/rumhead

[drmiller100]

3 inch column. 4000 watts is plenty. I use 36 inches of 12 or 13mm marbles. Marbles are very rare as almost no one else uses them.
Other things work equally or even maybe better.

[Rumhead]

Yes as wattage go i know 4000w is plenty. It will be SPP as packing, no expenses spared build is whats up.
i am after purest purest possible product and in haste too.
plan is to legal and then build more instead of bigger. I have found my calling.

With that in mind im still going for a high column ie 140-160cm to vm arm. Should be pleeenty of HETP..

Des anyone have anything negative against that column height with SPP?

With the LM head i feel i would gladly take more peoples experience/opinion on going slant vs cupped T boka RLM, speed in mind and control wise, so please all boka users chime in what you use and how fast it produces! AND how it behaves with light rum as thats why im going fully modular column with modular heads, everything is going to be cooked in the wessel with appropriate head and piece of column height.
//Rumhead

[Rumhead]

!Ohh and opinions on stable power control is also interesting, have been using SCR and notice the fall in the power lines well. Dont want that anymore. Stability and repeatability is the key in this build!

[Yummyrum]

LM and RLM are both effected by changes in supply voltage . Supply voltage variations means power variations , means vapour production variations .
As both LM and RLM send a metered amount either out , or back as reflux , the reflux ratio will vary with w supply variations and so will the ABV .

Where as ,a VM just splits the vapour .
Variations in supply voltage , and consequentially the amount if Vapour produced , don’t change the reflux ratio and as a result , the ABV remains constant.

I wonder why , if you have unstable mains supply , would you still consider RLM ?


Regarding the Crossflow condenser head .( Hammer head , Thors Hammer ) . Never really grabbed me , but I need to upgrade my 4” and I an seriously looking at it .

Although it is a height saving design , for me , I like that it can be done with cross tubes ( tube in shell) or even as a big old coil . I think I would go Tube in shell .

There is a really cool 3” build floating around that Stubbydrainer made . I’ll see if I can find a pic for you . He’s a LM fan , but the crossflow might get your juices going .

Edit : Doh , it was 2.5” still and used a coil
Anyway , nice bit of copper porn …. And inspiration
Note the fluid lock and vent on the LM take off . That section could be modified to redirect reflux back to column below reducer section for RLM if you wanted .

It uses a dual reducer collection cup . You could easily stick a VM takeoff in the reduced section .

D6B19076-488B-4189-8B99-413C3063EC6F.jpeg

[still_stirrin]

I agree with Yummy, if your power or water source are subject to flow variations, then the vapor managed (VM) stillheads are more consistent (stable through the variations). Also, liquid managed (LM) heads often run slower than VM heads at production to the spout.

And 140-160cm of SPP will certainly strip most of the flavor from your rum wash, since your goal is a high purity product. Funny thing is, that most rum makers like the rum flavor so they distill using a potstill, often double or triple distilled instead of refluxed. So, your choice of tools leaves me wondering about your solution.

It would seem that your requirements for the still would be better solved by a VM head. Oh well, a hobbiest will do what he wants to do and learn from his mistakes. Just be safe with whatever you do.
ss

[Rumhead]

I agree with Yummy, if your power or water source are subject to flow variations, then the vapor managed (VM) stillheads are more consistent (stable through the variations). Also, liquid managed (LM) heads often run slower than VM heads at production to the spout.

And 140-160cm of SPP will certainly strip most of the flavor from your rum wash, since your goal is a high purity product. Funny thing is, that most rum makers like the rum flavor so they distill using a potstill, often double or triple distilled instead of refluxed. So, your choice of tools leaves me wondering about your solution.

It would seem that your requirements for the still would be better solved by a VM head. Oh well, a hobbiest will do what he wants to do and learn from his mistakes. Just be safe with whatever you do.
ss

My preference when it comes to distillates and rum is always light tasting ones. I for the most part dont like aged products. Some aged ru is splendid but still, i prefer light ones as i am into mixing drinks and liqeurs and as such, a true clean azeotrope is the best base for almost all my uses.

But, this thread is already obsolete, im going E-ARC now when i have access to all the very very worthwile information out there. Best 30 bucks i ever have spent. That book is so well written it is unbelievable and thoroughly going from knowing nothing to knowing the most advanced smaller stills on the market.
There really is no turning back. Not with the added chapter about continous stills in the new edition...

[Big Stogie]

My preference when it comes to distillates and rum is always light tasting ones. I for the most part dont like aged products. Some aged ru is splendid but still, i prefer light ones as i am into mixing drinks and liqeurs and as such, a true clean azeotrope is the best base for almost all my uses.

But, this thread is already obsolete, im going E-ARC now when i have access to all the very very worthwile information out there. Best 30 bucks i ever have spent. That book is so well written it is unbelievable and thoroughly going from knowing nothing to knowing the most advanced smaller stills on the market.
There really is no turning back. Not with the added chapter about continous stills in the new edition...

Tell me about this book please, Im interested