Triple Coil Cold Finger Condenser

[sltm1]

Beautiful work!!

[moorem]

Beautiful work!!

Thanks Sltm1,
I'm just eyeing up 50" of 2" ID stainless tube for a new reflux column. That coil will fit in nicely with 1/8" clearance all around.

[moorem]

Thought readers might like to have a look at my latest construction for a fellow forum member.

This is a HUGE triple coil condenser. 11 inches long and made to fit a 3 inch off-set head. I've refined the construction of these coils a bit more and I think it pays off on the finished item:

Completed 3" coil

Look at those bends... pure magic

last view.

These big coils benefit from 3 PTFE spacers placed between each of the coils to make sure that they remain equally spaced from each other and within the tube housing.

[Doogie]

You are a copper porn master ... friggin sexy as heck

[bearriver]

You should sell those...

Seriously, there should be hundreds of those things floating around.

[Doogie]

ya, I would probably buy one at a reasonable price ...

[T-Pee]

The perfect symmetry is almost weird.
Did you get your methods from the MiB?

tp

[biggeroots]

I am proud to say that I am the owner of this latest piece of art! Thanks so much for it moorem

[just sayin]

Mr. "Wizard",

Your skill is unsurpassed. I stand in awe. Please continue to share your builds. Thanks you!

Just Sayin'

[moorem]

I am proud to say that I am the owner of this latest piece of art! Thanks so much for it moorem

You are welcome my friend.
I really enjoyed the finished article. Everything I expected came together just nicely. I think the symmetrical arrangement of the pipes terminating in the center tube looks good. I hope it performs well for you.

[biggeroots]

I am proud to say that I am the owner of this latest piece of art! Thanks so much for it moorem

You are welcome my friend.
I really enjoyed the finished article. Everything I expected came together just nicely. I think the symmetrical arrangement of the pipes terminating in the center tube looks good. I hope it performs well for you.

I decided to use copper wire that i had from an overhead power line, it fits perfectly between the coils. Even the spacing between coil and head are just right!

[moorem]

Now there is an example where two heads are better than one. I never thought of that solution, I was stuck with the idea of thin flexible PTFE tubing - which is actually quite expensive. What a good idea to use heavy copper wire and it looks good as well.
I was thinking about these condenser coils, if you are into making stills to try different models - boka, offset etc... then you would only need one of these and just move it about as required. I mounted both my 3" and 2" coils in turned PTFE caps so that they just plug into the tops of whatever head I'm working on.
By the way I'm not obsessed with PTFE its just that I have some in the workshop and its so easy to work with.
Thanks very much for sending these updates I'm quite chuffed to see one being developed and used.

[biggeroots]

Tis a pleasure to show it off. I just need to make a wire widget to suspend the coil. And maybe a custom 4 branch manifold.
I cant help handling it and admiring it

[moorem]

Got the manifold sorted for you...
Have a looked here http://www.ebay.co.uk/itm/Plastic-X-Cro ... 2eca58e594
I use these to feed or to take off from the three 6mm tubes. There is more than enough flow through these adapters and they are as cheap as chips.

[Doogie]

Guess who got a sexy coil ?????

Many thanks Moorem ... just an absolute masterpiece ... the big builders in N.A. should either pay you for a course, or pay you to make them for them.

I plan on taking a 2" cap and drilling the cap for the input and output, and a hole or two for the safety vent. This way it can be supported from above.

[moorem]

Thanks for the complement Doogie,
Yes I use a plastic cap (I used PTFE because I had some in the workshop) in the same way. Works a treat and means that its portable to other projects. Post some pics as the build goes - it would be interesting.

[moorem]

Well I'm still making them and learning and improving all the time (which is half the fun I think).
I just thought forum readers might be interested in my latest attempt at "copper porn"... a 9" long coil for a 3" head. Triple coil of course for a fellow forum reader.

Not assembled them yet but they are looking good on the bench as I packed in for this evening:

Before assembly

The real killer is the return bend to the cold feed for the center coil:


Getting it to return in on itself without the tube collapsing is difficult even with the jig already in place.

I'm changing the design of the bottom junction so that it provides a center run-off/drip point from the condenser coils while providing more support for the structure.

More pictures in a day or so.

[rad14701]

Nice work... What you really need to figure out is how to wind a double or triple helix in a single go rather than winding two or three separate coils and soldering them together... That would be the cats ass...

[moorem]

Hi Rad14701 - Far too difficult for a simple bloke like me to attempt. These triple coil assemblies are fiddly enough as they are. Imagine three lengths of soft 6mm copper pipe flapping around as they are wound. I think I'll stick with my current format, they seem to work out reasonably well.
Thanks for looking.

[moorem]

Well its done.
My newest creation all assembled, cleaned and pressure tested.
I used a different method for the bottom junction... what do you think?

Definitely a better finished format and the solid copper fitting assisted in providing a solid mounting for the junction of the 3 coils.

Pointed run-off connector

[Red Rim]

Oh my Gawd! That is almost more than I can handle. You have really outdone yourself. The bullet on the end made it perfect. I think I might go blind if I look at it anymore!

[moorem]

Thanks Red Rim,
Well I'm thinking of upgrading my own 3" Boka to one like this one above. My original triple coil looks like a dogs ear compared to this one. Don't get me wrong, it works OK enough but inside - I know what is wrong - the coils are too close and the run-off tends to fall to the outside instead of to the center. I also over softened the copper before winding the coils which means that it sags under its own weight and can distort if not handled carefully. I silver soldered the joints but, although the actual joints are as tough as old boots, the copper around the joint area is so soft because it has become annealed, that its a real problem with cleaning and maintaining between runs.
And apart from that these do look good.

[biggeroots]

Hi Moorem. Just to say i have used my tripple coil several times now and it works perfectly. I have noticed that only the bottom quarter of it actualy does the cooling even on full blast. Its that efficent.

[moorem]

Hi Moorem. Just to say i have used my tripple coil several times now and it works perfectly. I have noticed that only the bottom quarter of it actualy does the cooling even on full blast. Its that efficent.

Ah! Thank you very much for the feedback. That is really very kind of you to take the time.
Yes I kind of thought that these were a bit good. My own 3" coil (an early one and my first) knocks down my 3KW element running full on fairly easily enough. When I first tried it, I was so surprised with the volume of water coming from the outlet that I thought that I had a leak in a condenser joint. I still have a couple of gallons of distilled water in the garage from that first try.

Someone commented that they thought a triple coil was a bit of an "overkill"... well it is but at least you will never be left wanting for additional cooling capacity if you move it between still projects.

I think that they not only perform well but they also look good. I've had some fun working on a different end fitting where the coils come together, its tinkering really, the cooling capacity is the same, I think it just looks a little more professional.

Thanks again for the feedback.

[Doogie]

I still have yet to initial test mine ... life ...

I was unhappy with the pieces of copper I had to cobble together to get a maximum stack ... but I just scored a 6' piece of 2" thin wall (nicer for weight) for $30 ... so hopefully within a few weeks (after a massive rum run) I will push some sac runs thru the coil ... thanks again ... I will let you know what my dual does for me

[moorem]

Hi Doogie...
My second has also been a slow job. I finally got hold of a smaller stainless keg (30 liter) and this week I've only just finished turning and welding in a 1" BSP fitting for the element and a flange to attach the 2" column by tri-clamp to the 2" keg opening. I prefer working in stainless because I can soft solder it, weld it and generally work it without worrying about dents and bends occurring. It helps having a lathe and a good selection of 1mm stainless rods as I'm using stick welding not tig or mig. Next on my list is to sort out a PID thermostat and SSR linked to the sensor in the head so that I can accurately hold the head at a constant temp through the various stages.

[Hound Dog]

Hi Doogie...
. Next on my list is to sort out a PID thermostat and SSR linked to the sensor in the head so that I can accurately hold the head at a constant temp through the various stages.

Moorem, you do a great job with these coils. I have to tell you though, you are off base with the PID idea though. Controlling the temperature at the top of the column of a reflux still is not a function of controlling the heat input at the boiler. Heat input at the boiler must be hot enough to maintain boiling of the wash. Period. The magic 172 you are wishing to hold steady at the top of the column is a function of the reflux. The packing chemically separating the alcohols and the lighter cooler ones getting pushed to the top. The equalibrium of the column is a balance keeping the refluxing condensate just below flooding. Many times after the column balances and is in full reflux and equalizes for a while when I start my takeoff I find that if I bump the heat input up just a bit it helps increase the reflux to compensate for what I am removing. Temps hold steady this way.

I dint think a PID will understand to cut heat back to keep from flooding but increase it to keep the temp down step after step. This has been discussed many times in the past.

[moorem]

Hi Hound Dog,
I gotta do a lot more reading!
The techie side of me (computers, systems and control technology and chemistry) tells me one thing and everyone else tells me otherwise.
Its always difficult discussing things over text - I wish I could talk to someone or even better still have a beer or a long chat over a coffee or maybe even Skype.

[rad14701]

Hi Hound Dog,
I gotta do a lot more reading!
The techie side of me (computers, systems and control technology and chemistry) tells me one thing and everyone else tells me otherwise.
Its always difficult discussing things over text - I wish I could talk to someone or even better still have a beer or a long chat over a coffee or maybe even Skype.

What seems to be the problem with figuring what you need to know out...??? Very few people, if any, are going to be willing to get together or do Skype... Everyone else has been able to read and figure things out without the amount of hand holding you seem to be hinting towards... The information you need is all here and if you have the talents to make the condenser you have then I have a hard time believing that a simple packed column below the condenser would be overly complicated...

[moorem]

Well I've been reading and there are so many questions that keep popping up that the reading just can't answer all of them. And of course within every thread there are so many side comments that the topics often get diluted or take a different direction as people get fed up with diversions that they leave the thread undone. Not everyone learns the same way (evidenced by 25+ years of teaching) where experience has proven that a live discussion is often more productive than just "... read it here".

I'm also part of a Hydrogen development network (we have 3 patents to our credit) and each have come from developing different, quicker, cheaper or smarter ways of doing what others have been doing for years through the "same old" technologies. We achieved this through live chats where ideas can be bandied about in seconds and where creativity is live, real and fast. Reading and forum based conversations just does not cut it when it comes to research and development between colleagues.

Well I've been reading, and lots of it, power input based on temperature control of the head is not the way to go - OK - I can understand that but it has its place lower down. Power input based on reflux ratio within the column in order to maintain the balance of a column is a much more interesting proposition and certainly technically achievable.

So where I'm not looking for someone to "hold my hand" because, as you say, anyone can build a column however it may be made up (plates, packing, baffles etc.) because that is just plain and simple metal engineering and anyone with the tools can do that, I am looking for someone (or a group) who have the technical background and understanding who could discuss such matters as controlled and monitored reflux ratios, active monitoring of specific gravity, Ph (acidity), negative feedback loops, programmable logic control, monitoring of aromatics and other topics.

Some might say that I'd be killing the "artisan" element of brewing / distilling but for me, and I suspect many HD forum readers, to be able to achieve these things in a cost effective and reliably repeatable fashion would mean that their finished products would be better in terms of quality and safety.

I'd love to be able to post a system or method that is cheap enough for HD members to make that would allow reflux ratios to be reliably controlled, that might be able to monitor Ph or specific gravity to automatically predict the margins of fore shots / heads from the main run and tails. If these can be monitored and measured (and I suspect they can - I just don't know how yet) then they can be controlled. The "big boys" do it well enough but their kit costs many thousands of dollars. Technology is cheap enough these days, it just needs someone (or a group) to put the building blocks together in a cheap and reliable way.

So if anyone with the technical background and broad technological interest and wants to explore these issues further... I'm waiting.