CM the benefits and the downsides

Vapor, Liquid or Cooling Management. Flutes, plates, etc.

Moderator: Site Moderator

Post Reply
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

CM the benefits and the downsides

Post by Stonecutter »

Running my CM reflux still tuned down to a mere trickle while maintaining a decent takeoff rate (about 3-4 drops per second) results in a fairly flavorful whiskey with high abv 80%. To me that’s beneficial. The down side is that it’s a one and done run using reflux so you don’t have as much product in the end of your final run and you lose a bit of flavor. Anyone else out there experimenting with this setup?
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
Bushman
Admin
Posts: 17988
Joined: Tue Mar 30, 2010 5:29 am
Location: Pacific Northwest

Re: CM the benefits and the downsides

Post by Bushman »

I have a 4” diameter CM and I run it a bit faster and feel I get good flavor. Not sure I understand your downside, as I don’t think I would get a smaller amount of useable alcohol on my CM as opposed to a pot still?
User avatar
shadylane
Master of Distillation
Posts: 10364
Joined: Sat Oct 27, 2007 11:54 pm
Location: Hiding In the Boiler room of the Insane asylum

Re: CM the benefits and the downsides

Post by shadylane »

There's many of us running CM stills.
It's the most versatile and my favorite.
The Pro and Con of CM is it's controllability.
A CM works best with constant heat, such as electric.
It also works best when the cooling water temp is constant.

posting with Bushman
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

I’ll turn my reflux pump on late into my heads and turn off 3/4 of the way through hearts. That way I can gather that much more flavor towards the end and really make tight cuts into my tails.
Bushman wrote: Thu Jun 03, 2021 7:02 pm Not sure I understand your downside, as I don’t think I would get a smaller amount of useable alcohol on my CM as opposed to a pot still?
Yes it was a pretty piss poor example of a “downside”. Was hoping someone could come up with something better
shadylane wrote: Thu Jun 03, 2021 7:08 pm The Pro and Con of CM is it's controllability.
A CM works best with constant heat, such as electric.
It also works best when the cooling water temp is constant.

posting with Bushman
I absolutely agree. I keep my reflux/Liebig water supply between 78-81 degrees throughout the run. I use a 110V 2000W electric element. If I keep that throttled to 50V I can go through 90% of my run without touching the SSR.
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

I’ve never run a CCVM which is a really popular design. Why do you guys think CCVM seems to get more attention than CM? Is it because of build-ability?
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
Windy City
Site Donor
Site Donor
Posts: 1177
Joined: Fri Jan 25, 2013 10:52 pm
Location: Chicagoland

Re: CM the benefits and the downsides

Post by Windy City »

What is the diameter of your cm still that you are just getting drips.
I get about 1.75 liters every 12 minutes or 8.75 liters per hour from my 4” CM
The liver is evil and must be punished
Cranky"s spoon feeding for new and novice distillers
http://homedistiller.org/forum/viewtopi ... 15&t=52975
User avatar
Windy City
Site Donor
Site Donor
Posts: 1177
Joined: Fri Jan 25, 2013 10:52 pm
Location: Chicagoland

Re: CM the benefits and the downsides

Post by Windy City »

Is it bubble cap, perf plates or a packed column
Why would you have the reflux off in the beginning.
That is when you are trying to compress heads.
If it is bubble caps or perf plates how many?
Flavor will come through plates (cap or perf) very well.
Don’t turn off the reflux, that is one of the things a CM does well is shutting itself down for tails
The liver is evil and must be punished
Cranky"s spoon feeding for new and novice distillers
http://homedistiller.org/forum/viewtopi ... 15&t=52975
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

I’m at 2” (par for the course in my life in general :ebiggrin: ) if I run any faster I’ll start to flood a bit. Column packed with 2 rolls of copper mesh each about 18” long. I’ve been thinking I could probably pack a bunch more copper in there.
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

It’s nothing more than a reflux jacket sitting on top of my riser below my Liebig.
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
bluefish_dist
Distiller
Posts: 1502
Joined: Fri Jan 16, 2015 10:13 am
Location: Eastern Ia

Re: CM the benefits and the downsides

Post by bluefish_dist »

Stonecutter wrote: Thu Jun 03, 2021 7:47 pm I’ve never run a CCVM which is a really popular design. Why do you guys think CCVM seems to get more attention than CM? Is it because of build-ability?
Easy to build, easy to run. The favorite used to be a boka for the same reason, but the CCVM is even easier to build.
Formerly
Dsp-CO-20051
User avatar
NZChris
Master of Distillation
Posts: 13062
Joined: Tue Apr 23, 2013 2:42 am
Location: New Zealand

Re: CM the benefits and the downsides

Post by NZChris »

What puts me off building a plater, is the thought of doing cuts on every boiler charge. For four charges, the plater requires four sets of cuts. For four charges with a pot, you have to add on a fifth run, but that run produces four times the product to choose your cut from and the stripping runs for a four times larger ferment are fast and require little brain power after the first one.

I've just put down a wash of free fruit that is about 7 charges worth of wine, so 7 runs with cuts for a plater, or 7 fast stripping runs with my Charentaise style preheater setup, (which I should be able to do in a day), then two sets of spirit runs and cuts.
kimbodious
Distiller
Posts: 1199
Joined: Fri Apr 17, 2015 3:57 pm
Location: Far northern tropics of Australia.

Re: CM the benefits and the downsides

Post by kimbodious »

Stonecutter wrote: Thu Jun 03, 2021 7:47 pm I’ve never run a CCVM which is a really popular design. Why do you guys think CCVM seems to get more attention than CM? Is it because of build-ability?
Yes

Pros:
Cheap and easy to build.
Quick to learn to operate.
Not as finicky about fluctuations in water supply as a CM.
In most cases won’t require a needle valve for fine scale control of coolant flow.
You get nearly an instant response to changes of the position of the reflux condenser.
You can usually get away with plumbing the product and reflux condensers in series
You won’t need a valve like the VM has.

Conversely:
They can be a bit tall with the RC above the offtake.
I need to stand on a stool to change the position of the RC.
You need to use a flexible plumbing solution for putting the RC at different heights.
Tricky to make a mechanical remote or automatic RC position adjuster
I find it boring to operate so I only do one (BIG) run a year

Have I missed anything?
--
50L Beer keg boiler, 2200W element
Modular 2" Pot Still
opinions are free and everybody has them, experience costs you time
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

kimbodious wrote: Thu Jun 03, 2021 11:48 pm
Not as finicky about fluctuations in water supply as a CM.
In most cases won’t require a needle valve for fine scale control of coolant flow.
You get nearly an instant response to changes of the position of the reflux condenser.
You can usually get away with plumbing the product and reflux condensers in series
You won’t need a valve like the VM has.
Are water supply fluctuations really that common? I think most guys are running radiators with fans and a pump for cooling. Guys running smaller rugs can manage with a cooler and some ice with a thermometer. Sure, you need to basically feed ice every 5-10 minutes which can be a pain but it’s do-able. I would assume a needle valve would be beneficial no matter what kind of reflux design your running.
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
kimbodious
Distiller
Posts: 1199
Joined: Fri Apr 17, 2015 3:57 pm
Location: Far northern tropics of Australia.

Re: CM the benefits and the downsides

Post by kimbodious »

Water supply fluctuations are an issue for people running CM stills using tap water for their coolant.
--
50L Beer keg boiler, 2200W element
Modular 2" Pot Still
opinions are free and everybody has them, experience costs you time
User avatar
shadylane
Master of Distillation
Posts: 10364
Joined: Sat Oct 27, 2007 11:54 pm
Location: Hiding In the Boiler room of the Insane asylum

Re: CM the benefits and the downsides

Post by shadylane »

There's one thing a CM can do, that other reflux stills can't.
A CM can run at lower reflux ratios. That gives it a real advantage when making whiskey. :wink:
User avatar
acfixer69
Global moderator
Posts: 4832
Joined: Mon Dec 20, 2010 3:34 pm
Location: CT USA

Re: CM the benefits and the downsides

Post by acfixer69 »

This thread is a bit confusing because it is combining a CM packed column and a CM plated to aquire the same results. Both CM but desired end results are not the same. Plated CM is best for the tasty stuff one and done. Packed CM is for natural or voddie stuff. When talking CM end product decides what column to use.
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

I guess it’s Ford vs Chevy debate between CM and VM regarding neutrals? And the consensus for flavors is on the plated CM side?
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
User avatar
Saltbush Bill
Site Mod
Posts: 9677
Joined: Thu Mar 17, 2011 2:13 am
Location: Northern NSW Australia

Re: CM the benefits and the downsides

Post by Saltbush Bill »

Stonecutter wrote: Sat Jun 05, 2021 3:17 pm I guess it’s Ford vs Chevy debate between CM and VM regarding neutrals? And the consensus for flavors is on the plated CM side?
In theory you could / can use either sort for either job.......in reality one is the right tool for the job at hand , the other is not.
Trying to use the wrong one for the wrong job, just makes your life more difficult. Using the right tool for the right job makes it a breeze.
There are a ton of posts here on the forum written years ago about making whisky and such using detuned packed columns if you want to go down that rabbit hole.
User avatar
acfixer69
Global moderator
Posts: 4832
Joined: Mon Dec 20, 2010 3:34 pm
Location: CT USA

Re: CM the benefits and the downsides

Post by acfixer69 »

I’ve run plated CM since I made it and never looked back. CM is not just for voddies
User avatar
shadylane
Master of Distillation
Posts: 10364
Joined: Sat Oct 27, 2007 11:54 pm
Location: Hiding In the Boiler room of the Insane asylum

Re: CM the benefits and the downsides

Post by shadylane »

I've noticed 99% of the plated columns use a CM head.
Just guessing, a VM, CCVM or LM head can't be turned down like a CM.
A plated column needs enough reflux to keep the plates loaded but much more and flooding becomes a problem.
A CM is able to turn down enough to do that. The other options except for an offset LM can't.
But compared to a CM, an Offset LM would have more smearing.

Or so my alcohol persevered brain is telling me. :lol:

On a side note.
I don't think it matters what type of reflux head is used on a packed column.
Mostly packed columns are used for something like vodka or neutral.
Where high reflux ratios are the norm. An example for a 10:1 reflux ratio.
100% of the vapor goes up, 90% rains down as reflux and 10% goes in the jug.
User avatar
Yummyrum
Global moderator
Posts: 7657
Joined: Sat Jul 06, 2013 2:23 am
Location: Fraser Coast QLD Aussie

Re: CM the benefits and the downsides

Post by Yummyrum »

Not sure what you mean Shady . I have VM head on my 4” perfplate . Works just fine . Also works when I stick it on 2m x 4” packed .
Setsumi
Distiller
Posts: 1371
Joined: Tue Sep 07, 2010 10:23 pm
Location: Central South Africa

Re: CM the benefits and the downsides

Post by Setsumi »

Shady, myself runs plates with CCVM heads. i must tun very hard on propane to get a flood. on electric with a 3.6 KW heater it does not flood but i run around 3 KW on a 1.5 charge.

to Chris, these days i strip a charge on pot still and the combine it with mash for a full charge. it nets double of a single charge with good flavour.
My first flute
My press
My twins
My controller
My wife tells me I fell from heaven covered in white. Why did they let me fall?
User avatar
NZChris
Master of Distillation
Posts: 13062
Joined: Tue Apr 23, 2013 2:42 am
Location: New Zealand

Re: CM the benefits and the downsides

Post by NZChris »

Setsumi wrote: Sat Jun 05, 2021 9:54 pm to Chris, these days i strip a charge on pot still and the combine it with mash for a full charge. it nets double of a single charge with good flavour.
That makes a lot of sense. Extra esters because of the acids in the mash reacting with the higher abv from the strip.
Setsumi
Distiller
Posts: 1371
Joined: Tue Sep 07, 2010 10:23 pm
Location: Central South Africa

Re: CM the benefits and the downsides

Post by Setsumi »

NZChris wrote: Sat Jun 05, 2021 10:34 pm
Setsumi wrote: Sat Jun 05, 2021 9:54 pm to Chris, these days i strip a charge on pot still and the combine it with mash for a full charge. it nets double of a single charge with good flavour.
That makes a lot of sense. Extra esters because of the acids in the mash reacting with the higher abv from the strip.
i never thought of it that way, thanks for the headsup on the esters.
My first flute
My press
My twins
My controller
My wife tells me I fell from heaven covered in white. Why did they let me fall?
User avatar
Saltbush Bill
Site Mod
Posts: 9677
Joined: Thu Mar 17, 2011 2:13 am
Location: Northern NSW Australia

Re: CM the benefits and the downsides

Post by Saltbush Bill »

Setsumi wrote: Sat Jun 05, 2021 9:54 pm i strip a charge on pot still and the combine it with mash for a full charge. it nets double of a single charge with good flavour.
Ive done it that way to for a long time with my Rum Setsumi, ...sometimes I do UJSSM that way to..other times I single run it, all of the Uj however its run ends up in the same barrel....the blend seems to work for my taste buds.
User avatar
Hambone
Rumrunner
Posts: 509
Joined: Sun Jun 07, 2020 7:24 am
Location: MO, just around the bend...

Re: CM the benefits and the downsides

Post by Hambone »

kimbodious wrote: Sat Jun 05, 2021 12:25 pm Water supply fluctuations are an issue for people running CM stills using tap water for their coolant.
I used a pressure reducer made for RV to keep an even and slightly lower water pressure so flow doesn’t vary with my well pressure. Not so much of an issue now, but I used to have a faucet that came off my well line before my pressure tank and when pump would kick on it seriously increased pressure and flow...
Good judgement is the result of experience.

Experience is usually the result of bad judgement..
User avatar
bluefish_dist
Distiller
Posts: 1502
Joined: Fri Jan 16, 2015 10:13 am
Location: Eastern Ia

Re: CM the benefits and the downsides

Post by bluefish_dist »

shadylane wrote: Sat Jun 05, 2021 4:21 pm I've noticed 99% of the plated columns use a CM head.
Just guessing, a VM, CCVM or LM head can't be turned down like a CM.
A plated column needs enough reflux to keep the plates loaded but much more and flooding becomes a problem.
A CM is able to turn down enough to do that. The other options except for an offset LM can't.
But compared to a CM, an Offset LM would have more smearing.

Or so my alcohol persevered brain is telling me. :lol:

On a side note.
I don't think it matters what type of reflux head is used on a packed column.
Mostly packed columns are used for something like vodka or neutral.
Where high reflux ratios are the norm. An example for a 10:1 reflux ratio.
100% of the vapor goes up, 90% rains down as reflux and 10% goes in the jug.
Honestly I think the reason cm’s are so common is they scale the best. Ie much easier to make bigger. Because of this, that’s the type of head used for commercial distillers. It’s also easy to make if you are selling stills and have the capability to make a shotgun condenser. Yes, they can run lower reflux rates than a VM, but I made a 1:1 VM and never ran it even close to 1:1. Couldn’t control the abv like I wanted. The lowest reflux I would usually run was 4:1 and even that only lasted for a small portion of the run, maybe 10%. Usually I was 4-5 turns open out of 20.
Formerly
Dsp-CO-20051
User avatar
Stonecutter
Site Donor
Site Donor
Posts: 1911
Joined: Fri Apr 16, 2021 2:40 pm
Location: Somewhere within the Milkyway

Re: CM the benefits and the downsides

Post by Stonecutter »

Windy City wrote: Thu Jun 03, 2021 7:58 pm Is it bubble cap, perf plates or a packed column
Why would you have the reflux off in the beginning.
That is when you are trying to compress heads.
If it is bubble caps or perf plates how many?
Flavor will come through plates (cap or perf) very well.
Don’t turn off the reflux, that is one of the things a CM does well is shutting itself down for tails
After gaining more experience and understanding of my equipment my processes have changed. I now compress my heads to varying degrees based on what’s in the boiler. For instance, as an experiment, I ran a brandy last week and didn’t compress my heads as much in the hopes that I could drag more flavor out of them. Maybe there’s a better way of doing this? I’ve got a mesh “trap” on the bottom of my sight glass that sits just below my reflux chamber. I add about one inch of rashing rings there and it acts like a small plate. I have two bundles of copper stuffed into my column below that. As SSB explained there is a rabbit hole for hobbyists that run tuned down reflux rigs and I can see myself naturally heading that way.
Windy City wrote: Thu Jun 03, 2021 7:52 pm What is the diameter of your cm still that you are just getting drips.
I get about 1.75 liters every 12 minutes or 8.75 liters per hour from my 4” CM
I’m definitely running faster now with better results. It’s exciting to make those small steps towards becoming a decent hobbyist. I’ve got a long way to go yet and I appreciate everyone’s input.
Freedom had been hunted round the globe; reason was considered as rebellion; and the slavery of fear had made men afraid to think. But such is the irresistible nature of truth, that all it asks, and all it wants, is the liberty of appearing.
-Thomas Paine
Post Reply