FLUTE TALK

[freespirited]

Probably PP guess it depends on the upcomer dia. I spoke with OD last week he said to use a 2" cap which would justify a 1.5" upcomer. For that I would use a 1" downcomer. However, OD may have been talkin a weir wall setup, cause I cannot get a 2" cap and a 1" downcomer to fit. So its gonna have to be 3/4". I know the OP was talkin perf plates so I would go with at least 3/4. I may be wrong but wouldnt 1" allow for faster run? More heat with less chance of flooding?

[Padraig]

I started a separate thread to discuss my flute. Link: http://homedistiller.org/forum/viewtopi ... 17&t=28395. Just added drawings there. Glad to have your input. -P

[NcHooch]

Listen up here for a minute yall ...I want some feedback on somethin.

My usual routine when running my flute goes something like this:
heat up .
once the vapor hits the dephleg, I throttle down the propane a LOT ... (if I don't, the top plate hold 70% of the distillate)
run in full reflux for 30 mins and then start throttling back the coolant to the dephleg ...
at that point , collection starts .

As I was running my rig the other day, I was thinking about how my still runs, and some stories about how other flutes flood the bottom plate. The thought occurred that in order to ensure proper operation you really need to

• Provide enough heat/vapor to keep the fluid on the plate.
  Balance heat/vapor with cooling capacity of dephleg for the mode of operation (full reflux or collection).
  Yet, too much vapor will create too much pressure under the plates and disable your downcomers.

I think the reason plates get flooded is not from too small a downcomer, it's from too much pressure under the plate slowing/stopping the downward flow of distilate in the downcomer.

You can change the heat, and most of us can change the cooling in the dephleg, which should be enough to keep most of the plates working. We cant change the open area of the plates which has a major effect on the amount of power we can run, because we don't want excessive pressure under the plates which will ultimately blow vapor up the downcomer, but also disable the downcomers by preventing or slowing flow..

I wonder if there is a difference in the amount of pressure between the different plates in a flute, that would require a different amount of open area on each plate in the column.

Hmm

[Prairiepiss]

I've been thinking about the pressures present within the still spurring operation. For some time now. Finding actual measurements of hobby scale stills is well almost non existent. I'm in the middle of some kinda experimental still parts. And will be making a test adaptor. This adaptor is going to be able to test WC pressures, flow rates, and temps. I plan to use it at different stages of the column. Between plates, between packed column sections, on top, and on the bottom of the column. I also plan to out the same test ports in the boiler before the reduction for the column.

Now that I let that cat out of the bag.

My thinking is. ( haven't ran or built a perforated plate still) There is a pressure drop at each plate due to vapors collapsing. And by knowing how much of a drop is at each plate. The perforated plates can be adjusted accordingly giving a even pressure at each plate. I think that maybe? Not only the perforations sizes will need to be adjusted. But also plate spacing or volume of the chambers. And possibly liquid depth. All of which can contribute to the pressures.

Unfortunately I will be starting the experiments with a bubble cap setup. Then moving on to perforated plates. So it mite be a bit before I get any data on them. But once I get into the new house and get my shop setup. I'm gona dive into it. And hopefully get some usefull data to share.

Yea I know most of this can be figured out mathematically. But that hurts my simple little head. So I want hard proven numbers that can be posted for all to see. I will also be doing flowbench experiments. More to come on that later.

But I would love to see this discussion get going. So I could hear others thoughts and maybe think of more testing I could do.

[emptyglass]

Funny you mention that Hooch,
My runs go similar to yours, big heat, then throttle back, and so on, but I was watching the behavior of the J cup (I have a window there). Last run I did was the first run with my new fill port and drain. The fill port showed no leaking until all the plates were full, then mr drip appeared. I tightened the tri clamp a little and it was fixed. But it led me to question why it didn't leak untill all the plates charged. Then I guessed that it must have been the weight of all the liquid on the plates creating a reasonable increase in pressure in the boiler.
Then, watching the j cup on the bottom plate, I noticed this pressure acting on the surface of the j cup and the bottom of the plate. As my gas bottle was running low, I had screwed up the heat to compensate (yeah, I know, I should just get it filled) and was running a little above normal. Dropped the heat back to normal and all was good.
But it sort of backs up what you observe. The pressure between plates is what stops the downcomers working.

Mr Piss, you may be able to back this up in time (now we know about your cat in the bag!) but I'm sure this would apply more to perf plates that rely on sysem balance more than bubblers do.

[Dan Call]

Perhaps a silly question.

Most of these videos I've seen show the plates really full and bouncing.

I see picture of commercial scaled collums, they have alot more plates/sight glasses.

What if you had a 4 ft. collumn with 6 or 8 plates sight-glasses. Wouldn't that cut down on a single plate being too full?

[Prairiepiss]

Perhaps a silly question.

Most of these videos I've seen show the plates really full and bouncing.

I see picture of commercial scaled collums, they have alot more plates/sight glasses.

You need to also look at what that commercial still is making. Many are designed for one specific spirit.

What if you had a 4 ft. collumn with 6 or 8 plates sight-glasses. Wouldn't that cut down on a single plate being too full?

The liquid level isn't determined by the number of plates. It's determined by the plate drain design. So adding more plates won't change it unless you change the drains too. How hard you run it will make a difference on the liquid levels too. Adding plates will just change the ABV and flavor profiles of the output. You would need to design the liquid level you want on the plate into the build. Changing drain size, and placement, plate hole sizes for perforated plates and size and number of bubble caps. And determined at what power level you will be running it at.

A 4' column not including the dephlagmater could hold 10 plates with a 4.8" spacing. That's well within what has been found good plate spacing. But unless you are shooting for a neutral? Not sure why you would want to?

What is your reasoning for lowering the liquid levels on the plates?

[Dan Call]

Well currently I'm using the "Smiley" fractioning set up and I"m more happy with ABV when I run more packing more slowly. I also run a very clean distillate and take a long
time to rack. I let it settle completely before racking more. It really does effect the taste. With more purity taste is not reduced, it allows more flavor complexity and less junk if you're using grain. If you're using sugar, well sure, it's just pure sugar vodka....who cares about that? Run a pot still with well setlled sugar wash, no big deal there. Where's the challenge in distilling sugar? Only Rum with the oils added back in (read Pugi's rum oil discussion) is an interesting sugar based setup.

I'm going to build a plate and I want the option to run alot of plates, slowly. It just seems like the way to go.

Not intereted in neutral at all, I'm doing all grain barley, rye, and corn, with some peating on the barley, not peat peating, but wood substrate peating.

THat's it. It's easier to reduce plates than to add them.

[Prairiepiss]

Why would you want to run more plates slowly? If your not interested in a neutral?

Sounds like to me your after a more flavorfull drink? So build accordingly.

Start with 4 or 5 plates. Try it out see what you get. Then make an add on with 4 or 5 more plates. That you can put under the first build. I wouldn't start out with 8 to 10 plates. Harder to remove them later. If your not happy with the outcome.

I bet you would be happy with the 4 or 5 plater. Once you learn to drive it for what you want.

[Dan Call]

Yes I am interested in grain/peat character. So the assumption here is less plates more taste? What about plate size? Larger plate=more taste?

[olddog]

What about plate size? Larger plate=more taste?

The size of the plate has got nothing to do with taste, it's proportional to the diameter of the column.


OD

[Sungy]

Just some observations of my setup.
The original build used 1/2 inch OD downcommers and 3/4 caps suspended above the valve plates. This resulted with excellent results in the early stages of the run. But when the alcohol content in the wash started to go down a bit the traps would go dry and vapor would go up the downcommer and the plates would flood becoming mini thumpers. This was because the traps where to small and they where suspended in the vapor path. To fix it I used U bend (180) traps. They increased the trap liquid volume allowing me to run harder and also now sit 1/8 inch above the valve plates ( surrounded by liquid ). All was good except for the bottom plate which would still blow out. This was because the pressure in the bottom of the column exceeded the trap size. To fix this I went to 5/8 downcommer and U bend. All works well now untill the deep tails. When the temp rises to around 93'C on my thermometer I start loosing plates from the bottom up ( blow out ). If I notice this happening now I go into full reflux for 5 - 10 min and build up the plate concentration and the blow out is prevented. I continue this method once more then shut the reflux off and crank up the heat to gather the last of the good stuff to be recycled in the next run.

[emptyglass]

Yes I am interested in grain/peat character. So the assumption here is less plates more taste? What about plate size? Larger plate=more taste?

Alcohol dosn't have any taste. If its made from potato or sugar dosn't matter. You will only ever get 96% out of a still. Its the other 4% that tastes (good or bad)

3 or 4 plates is all you need if you want to carry some flavor from grains. With 11 plates your making vodka.

Most flute users here say the same thing, they run comfortably not trying to screw as high an ABV as what the same rig can make run differently. I know I can do a slow run and get up to 95%, but I can run it a bit quicker and get 91%. It dosn't take as long, and my sugar/grain product has more taste.

If you run/have run a pot still, you will know the difference speed of the run can make to flavor. No different with a flute, but you have more control.

[MexicanCustard]

I'm a long time lurker with some questions before building my first flute.

In OD's first flute his deflag was a single smaller pipe running straight through a larger pipe. What I'm seeing on all of the new builds is the shotgun deflag. I can't seem to find any discussion where the two were compared and the reason everyone is using the shotgun over the single pipe design. Since this is the new Flute Design thread, can someone enlighten me on the difference in the two designs?

I really like MR-E's modular design which is similar to the Hillbilly Flute. Are there any downsides to this type of design other than the greater chance for leaks?

I just want to say hats off to everyone who participates in these forums. There's a lot of knowledge here.

[NcHooch]

I'm a long time lurker with some questions before building my first flute.

In OD's first flute his deflag was a single smaller pipe running straight through a larger pipe. What I'm seeing on all of the new builds is the shotgun deflag. I can't seem to find any discussion where the two were compared and the reason everyone is using the shotgun over the single pipe design. Since this is the new Flute Design thread, can someone enlighten me on the difference in the two designs?

Well, I think it goes something like this, OldDog proved that the simple single-pipe dephlag did the job just fine.
When the design started getting copied, it appears the "bigger is always better" mindset took over and the shotgun was adopted as the rainmaker of choice .I also tend the think a shotgun is cheaper to build vs. the dephlag with the cone-shaped endplates in the original OD flute. the efficiency of the shotgun is hard to beat, and I'd venture to say that most of the shotguns would work perfect if they were 2-3" tall, instead of 4-6" .
hope that helps

[LWTCS]

And to expound on NC's answer,,,,,the folks running a recirc pump and smallish reservoir also wanted wanted to insure that they could get the best performance....
All the while,,,,no one really knew how small was too small to achieve 100% reflux.....not even the eggheads were chiming in within the context of how the rigs were being driven as it took some time before the eggheads could get past the fact that we were using the condenser as more than just a "partial" condenser.......

Someone please correct me if my perception is out of line.

[mash rookie]

And to expound on NC's answer,,,,,the folks running a recirc pump and smallish reservoir also wanted wanted to insure that they could get the best performance....
All the while,,,,no one really knew how small was too small to achieve 100% reflux.....not even the eggheads were chiming in within the context of how the rigs were being driven as it took some time before the eggheads could get past the fact that we were using the condenser as more than just a "partial" condenser.......

Someone please correct me if my perception is out of line.

You are correct Larry. The shot gun approach works best because of shear size. Consider the total surface area for cooling vapor and volume of water. Smaller units like a coil require much more water to do the same amount of refluxing. I believe a drop in works better than a modular shot gun dephlag because you have the additional surface area between the column wall and condenser.

I ran sexy girl yesterday and barley had a trickle of water exiting the dephlag taking off at 85-90%. My two rigs that use coiled reflux condensers use considerably more water to reflux and won’t keep up with my flute on speed for that reason.

MR

[Prairiepiss]

I would like to add my experience with my dephlegmater. Well its a reflux condenser on a cm column. But I haven't seen much in the way of experimenting with what I have found.

I built mine kinda last minute addition to a pot still. And I didn't expect it to perform as good as it did. It's only a 2" column. I added a coil with a 2" Id made of 1/4" copper. There is 7 foot in the coil. But I placed it in a 4" ball section at the top of the column. What I think happened was. The added expansion area of the ball made the small condenser more efficient. I can knock down 2700w with it no problem. As small as it is that's the only thing I can think of that increased the efficiency of it.

I know its not the norm. But I would like to hear thoughts about it? I'm thinking about a bigger experiment along the same lines for a plated still.

[MexicanCustard]

What about the modular design? Pros and Cons?

[moonshine guy]

I built a flute with 4" sanitary tee's. She stands 9' tall and one heavy SOB! Runs great and always put out 186P. I'm going to build one out 4" sight glasses, so it will be a clear column. I think this will be a bad ass column!

[LWTCS]

Pros.....
Modular is always handy as it allows you to modify a configuration with out having to do anything but assemble you parts differently. More flexibility with modular. More ways to skin the cat........
Cons.....
Poorly constructed bits might make for more potential for leaks.......

Can't really think of other cons.

[moonshine guy]

Yes on the leaks, use Teflon seals at first with my flute and it would leak on heat up and most of them would stop and some would not. Switch to epdm seals and no leaks at all from start to finish! On this next build, I have bought silicone seals and see how they work and hold up!

[emptyglass]

What about the modular design? Pros and Cons?

Pro's; Easy to make changes.

Con's; No point changing it once its right.

Pro's; In a way, its a bit easier to make smaller components, then put them together.

Con's; Its still going to be the same size once it's finnished.

I think the modular option is good if you want to use the bits of your flute for other reasons, perhaps drop the top off and convert to pot still, maybe use the product condensor somewhere else and so on...
I made mine modular, but so far havn't changed it (other than the plate tree). I do have a plan for a worm and bucket condensor off my old pot still, but its just for fun, I don't expect any gains.

Yes on the leaks, use Teflon seals at first with my flute and it would leak on heat up and most of them would stop and some would not. Switch to epdm seals and no leaks at all from start to finish! On this next build, I have bought silicone seals and see how they work and hold up!

Guys! If you are forced to look for an alternative to teflon seats that you can't get to seal, don't use rubber, use cork!
It works well enough, and is a lot safer/better/cheaper than rubber. This thread is not a materials debate thread, but modular flutes end up with a lot of joints that can be tricky to seal. Cork can be a friend.

[mash rookie]

PP, You no longer have a pot still. You have a CM reflux column. Welcome to the club. Your coil and water flow are well matched to power out put and temp at the top of the column. That is why it works. I run 5500 watts. It would not touch that.

Modular is the only way to go if you want to have a multiple component still head and you are going to change configuration each time you run something different.

A well designed still will allow you to make different products by running it differently. There are plenty of micro distilleries that have shown this.

A simple example is the production of whiskey. It can not legally be taken off above 150p. Why is that? What would they have if they took off at 190p

If you want to go to the extra work of building modular go for it!

[Prairiepiss]

It's always been a CM still MR. And yes I feel I lucked out and got a good match for my power. But that's why I'm asking. I know it won't work with the 5500w I'm going to. And I'm needing to build a new one to go with the rest of my new build.

So my question is. Will providing a vapor expansion area around a condenser coil improve its efficiency? Expanding vapors will cool them some. But it will also slow the vapor speed so it has more time for contact within the cooling chamber. And the exit restricting it again will slow it down just a bit to. And the outside having more surface area would have a better chance to get some paralistic or what ever that word is reflux. I no not much but?

My biggest problem with mine is while taking product off its almost to efficient. For my power input now. But I know it has its limitations. But I almost have to cut the flow off to get the desired output. So something is going on here? Just trying to figure it out. So I can apply it to my new plated build.

[Sungy]

Ok so Im just gonna throw this out there and see if it sticks. I was thinking the other day about a new bigger build. My thoughts came round to the dephleg condenser. How can I improve on this? Well here is what I see as the biggest problem with all current builds. The water volume in the Dephleg itself is to large. This causes thermal lag. The time it takes from adjusting the cooling valve to the water temperature actually changing is way to long. In comparison a Liebig condenser holds much less water.

So in my twisted way I thought about a six barrel shotgun Leibig. I was thinking of making 4 tube sheets ( 2 for each end ) Two will have 3/4 inch and two will have 1/2 inch holes. Space the two plates 3/8 inches apart at each end to make a space for the water to enter the 3/4 and have the 1/2 run right threw the 2 end plates.

The pink areas are vapor path
The blue are water
The white is open air space
( note the dashed lines are the plates and are continuous)

Has this been tried? As it seems to me a great reduction in water volume. Its still a dephleg and the size should end up the same.
So what do you guys think? Am I on to something here or just beating the same drum as someone in the past?

Edit for clarity

[emptyglass]

So my question is. Will providing a vapor expansion area around a condenser coil improve its efficiency?

It can't hurt, I'd be pretty sure of that. So I don't think you will lose anything, but you might have a bit to gain.
You might have to pave the way on this one PP.

How would you go about it? I'm picturing a big ball with a large-ish diameter coil- am I on the right track?

As the others have said, I find the 5 inch long dephlag I have responds ok, can knock down all I throw at it and really uses very little water when in partial reflux. I don't know how much more efficient you can make one of these.

[myles]

I dont think anyone on here has talked about the german way that they look at the dephlegmator issue. What they use is effectively a wide short coldfinger, more like a cold bucket as I think it is usually about 1/2 the diameter of the column.

I don't suppose it would get 100% reflux but I personally don't see this as a big issue. Too me it makes sense to have two condensers (possibly in the same physical volume), one running hot to just provide the neccesary condensate for during the run, and the second to switch in as required to run flat out and provide 100% reflux.

I have been thinking about this and believe you could have a short 1.5" or 2" coldfinger for the dephlegmator, surrounded by a double or tripple wound coil to provide the 100% reflux.

[mash rookie]

PP I don’t believe that additional expansion area will help. Yes vapor speed will slow but contact area is not increased.

Thermal transfer is much greater with liquid than gas. You can cool a piece of hot steel with a fan in fifteen minutes or quench it in cold water for five seconds. That is why we need a very large surface area to be in contact with the vapor.

I am working on some new designs and have been giving a lot of thought to my reflux condensers. For simplicity I would love to build a double or triple wound coil but found that more difficult then I had thought and provided much less surface area. i am still looking for a kiss design.

Sungy the problem with your type of design is in construction. The more joints and complexity the more opportunity for leaks. Okay if you are only going to build one but a pain if you are going to build many. I don’t have an issue with slow response with my dephlag. It works great.
If you want less water,a flatter dephlag would hold less water. Instead of ¾ or 1” tubes using as many 3/8” or ½” tubes as possible would create a greater vapor surface contact.

Myles, I have considered something like the German concept. I think we just need a large heat sink. Something like a three inch diameter ball dropped into a four inch column. No through tubes. Cold in the bottom hot out the top. Think backwards Liebig. ???

[MexicanCustard]

More questions...

Has anyone built and used both a perf plate and a bubble plate and if so can you tell me the differences in performance/quality? I think that the bubble is harder to build but it looks like its easier to get premium results. Can anyone confirm that? I was all set to build a perf plate and then I saw emptyglass get crucified over on another forum. So, I'm having second thoughts and I'm considering building a bubble instead. Skill and material are no problem for me, I've been working in the mechanical/plumbing industry for 22 years. So if the bubble is better, disregarding cost and ability to work with copper, then I would rather build the bubble.

BTW, my plan is to monitor the rig using a laptop and an Arduino. With the current cost of control valves I don't know if that will happen but for now it's the plan.