vm lm design sketch

[greenthumb]

hi guys, after previously owning a cm still, and building a large pot still and a small pot still I have decided to build a vm/lm combo as I miss my neutral and really fancy
getting to grips with something a bit more technical, and being able to compress the head and tails would be great, so here is my design taken from various others and snippets of info I have read like not reducing the vm take off until after the 90

so here goes

rsz_lm-vm-design.jpg

let me know what you guys think, ,any mods recommended?

[still_stirrin]

Check out Rad's concentric design for the reflux LM head. And putting the VM valve in the vertical can/will result in condensate pooling above the valve.

I run a LM/VM combo, ala Rad, and I like it a lot.
ss

[still_stirrin]

To refine my response, I recommend putting the VM valve in the horizontal run before the elbow. But in order to maintain minimum reflux ratio, use a 2" diameter valve. Now, this is a high dollar proposition, so a good compromise woud be to reduce to a 1" or larger valve. A 1" valve raises your minimum reflux ratio to 4:1, which I believe is a fair $ to performance compromise.

Making the head modular with a Triclover joint would allow you to swap in a 90 elbow in lieu of the reflux head so you could always run in pot still mode, provided you put an inline union in your VM product circuit.

I suggest this as it's the way I have mine setup. It allows me to operate any way I want (excluding CM).
ss

[greenthumb]

i wasn't too concerned about the pooling, i would just dump it before I started collecting, the original idea was to run a 54mm column reduce to a 54 x 35 x 54 tee and have the 35mm gate valve on horizontally like you say, but then I read what rad wrote that it would be better to run full bore until after the 90 and place the gate valve after the 90, as like you say buying a 2" gate valve is mega bucks, and will deal with any pooling at the time, im trying to make the hole thing modular with tri clamps and ferrules so its easy to clean, hot swap, and modify and parts as and when wanted.

do you have any pictures of your rig? to help get my head round it?

[greenthumb]

wouldn't the reflux ratio be better the way I have sketched it having it 2" all the way to the gate valve after the 90 then reducing it? then how about adding a drain valve to deal with the pooling just before the gate valve.

my original design was this with a 54x35x54 tee going horizontal to the gate valve then the 90

rsz_lm-vm-design1.png

[still_stirrin]

wouldn't the reflux ratio be better the way I have sketched it having it 2" all the way to the gate valve...?[/attachment]

Better is a "qualitative" term. If the goal is to reduce the reflux ratio, then yes, maintaining 2" to the vapor management valve is "better". Similarly, maintaining the size of the vapor branch off the column.

Howver, a slight increase in reflux ratio isn't necessarily "bad" either, especially if you're trying to pull higher %ABV product off. You're trying to improve the reflux through the column anyway, so the $$$ saved with the VM valve size reduction has more merit.

If you're trying to emulate a pot still with a 1:1 reflux ratio, then the take off reduction is a detriment.

Me...I simply change heads for pot still (stripping) runs.
ss

[palinkagus]

Greenthumb, the 22mm liebig cooler on the LM outlet in your sketch is unnecessary since the reflux condenser at the top of the rig is already condensing the the vapors that collect on the bottom slant plate. I would recommend changing the 1/4" stainless steel gate valve to a needle valve. That way you can, with great precision, bleed off the fores/heads one drop at a time prior to opening VM takeoff.

[still_stirrin]

Here's a link to my build:
http://homedistiller.org/forum/viewtopi ... 6#p7207937

ss

[still_stirrin]

Greenthumb, the 22mm liebig cooler on the LM outlet in your sketch is unnecessary since the reflux condenser at the top of the rig is already condensing the the vapors that collect on the bottom slant plate. I would recommend changing the 1/4" stainless steel gate valve to a needle valve. That way you can, with great precision, bleed off the fores/heads one drop at a time prior to opening VM takeoff.

The liquid will still come off of the still hot. Having a small Liegig product condenser for the liquid takeoff is a good idea. I know this for a fact.
ss

[palinkagus]

The liquid will still come off of the still hot. Having a small Liegig product condenser for the liquid takeoff is a good idea. I know this for a fact.
ss

ss, the liquid that is being removed from the LM outlet is basically a waste stream from the distillation process (fores & heads). Dealing with the minor volume of "hot liquid" IMHO is not worth the cost and complexity of an additional component to the still head.

[still_stirrin]

Unless, of course, the OP prefers to run the still as a LM, that is liquid managed still. Then the product will all come out of the LM takeoff.
ss

[greenthumb]

My mistake on the plan, the lm take off valve is a 1/4" needle valve, not a gate valve, so I can have accurate control.
I must admit I have read a lot about reflux ratios but not enough in a simple format as to understand it, when I want to run in pot still mode I would just remove the lm head and clamp on a blank plate, for stripping runs I could couple the lm head straight to the keg? As with rads concentric design?

The way I see it is I can build any of these configurations annotated here viewtopic.php?f=17&t=10987
I have the parts to build any variation, but the gate valve will remain 35mm.

[DAD300]

Don't clamp an LM head with a 1/4" takeoff to a keg, block the top and pot still through it. That's a BOMB! Not the bomb. The volume of vapor off a keg will overwhelm a 1/4" takeoff.

Your VM head is your pot still.

Pic A- Next, these guys are telling you the truth. Your valve on the VM, on the vertical, will pool a few ounces. That's enough to contaminate the next quart.

The VM product take off inside the Graham is too small. A Graham hanging on the side of a column is also very heavy. 8mm is ~1/4" and will huff and spit even cool product. Make it bigger/better and you'll only make one that will work on the next still.

[greenthumb]

I have run this Graham on the side of this column for months now in pot still mode even with the 8mm output, and it strips very fast, and the weight has never been a issue, I agree with the pooling issue after reading more threads I have decided to run the valve horizontally just need to decide now the best way to tee from the column

[greenthumb]

Sorry DAD think you miss understood, there is no bomb, and never is a closed system, I wasnt going to block the top of the lm head, once I removed the lm head I could cap off at that junction and run the vm as a pot, or just put the lm head as it is onto the keg

[DAD300]

Good deal...

[greenthumb]

DAD have been thinking about your concerns about the graham, I am building this still modular, so if it does hold me back in any way, I have 1 prototype liebig arm, and 2 normal liebigs that will more than cope, and they are already built modular I can add or remove them at my leisure and see what's best

[DAD300]

Even better....ready to go backups.

[greenthumb]

So after some narrowing down it looks like either option 1 or 3 to keep the valve horizontal what do you think guys viewtopic.php?f=17&t=10987

[DAD300]

I like #3 better than #1.

#1's constriction speeds the vapor and makes adjustments harder.

If you put the LM below the VM, you could get rid of the VM valve all together...save money...

COMBO HEAD.png

[greenthumb]

Yeah #3 made more sense to me, but all the original designs are of #1 Wich is what through me, I will go with #3 ,

I must admit if it wasn't for the fact I already have the parts I would be surely interested in your coil controlled vm, I was reading your thread last night, I may look harder at that when I build my 3" version!

[greenthumb]

have digested more information and parts available taken into account I have redesigned my drawing accordingly, please comment accordingly

lm-vm-design2_opt.jpg

[still_stirrin]

I like it greenthumb. I like it a lot.

Boka LM head with a VM take off and interchangeable product condensers (shotgun & Liebig) for performance adjustability/demands. It give you a lot of flexibility. I bet you'll use the shotgun most though because of its knockdown power. It'll handle anything you throw at the still.

Your use of triclover connections gives you good modularity too, for present and future options (evolution of distilling desires).

Build her, clean her up, and get the product/rewards of your efforts.
ss

[Danespirit]

That rig looks realy fine..
It should serve you well for many years.
Keep on posting pictures.. I wonder how your "prototype" Liebig on the VM side would perform..interesting design..

[greenthumb]

Thanks for your input guys, definitely putting all my eggs in one modular basket on this design for sure, can't wait to see how she will run, long way off yet though, all parts purchased and in the post, mid January build completion date hopefully, got carried away today and built 2 burners for my forge and furnace, was supposed to be winding a helix coil

Merry Xmas all!

[greenthumb]

The 1mtr column is now packed with copper mesh and ferruled both ends, insulated and wrapped ready for cleaning runs once other parts are ready

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[greenthumb]

Latest bit of work today, got to work out and mark the cut angle of the slant plates yet, and buy some more gas, run out while heating the shed today!

So here is the latest pics,, still gotta clean her up propper after I silver solder the plates and lm branch.

I managed to mangle the end of the reflux coil (what do I call this type of coil?) on the mandrel, probable would have been ok but I decided to cut it out and bend a new piece to replace it

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[greenthumb]

Another day in the shed has got me lot closer!

The plates and ports have been loosely fitted awaiting soldering tomorrow, ran out of time today, pretty impressed with the cut from the band saw!

big thanks to the guys here for the 2" revised boka plates template , I believe rad posted the first one and Usge posted the revised version

http://homedistiller.org/forum/viewtopi ... &start=180

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[thatguy1313]

I'm liking it, greenthumb! You're gonna get a fine drop outta that rig!

[greenthumb]

I'm liking it, greenthumb! You're gonna get a fine drop outta that rig!

Thanks, I'm hoping so can't wait to run some neutral again, sure it's been over a year since I last ran some, ran out a long time ago, have plenty of rum though

Will be good fun getting used to how to drive her, packed, detuned, lm, vm, it's gonna be interesting!