Quick Condenser Q

[lacedspirits]

I'm putting together a 2" Compound (Boka-style) Still. I was planning on using 3/8 tubing for the top condenser coil but after drawing it out I can tell that I'll only be able to fit a single 3/8 coil, not a double. I have figured out that a double coil is possible to make using 3/8 for the outer coil and 1/4 for the inner coil, and just connect them with a flair fitting (H2O in 3/8 and out 1/4) Or maybe making one 3/8 outer coil and just soldiering a plate in the center of the coil half way up and another further towards the top to direct the vapor towards the coil. I used to do alot of plumbing work so I have tons of fittings and around 50 feet of 3/8 and 1/4 tubing so supplies aren't an issue. I've been running this through my head for almost a week now and am getting to the point where I'm wondering if I'm over-thinking it and maybe I should just throw the 3/8-1/4 double coil together and just see if it works.
Any insight would be greatly appreciated.
Thanks in advance,
ls

[olddog]

I could be wrong, but the flow through the condenser will be limited to the diameter of the 1/4" tube, you might as well just wind a double with 1/4"and save the trouble of having to connect two tubes together of different sizes.



OD

[Braz]

Yep, what olddog said. 1/4" double wound coil 8-10" long should give all the cooling you need for a 2" Bok. You can increase its efficiency by inserting an unwound copper scrubber in the center of the coil but it probably won't be needed.

[HookLine]

Please don't take this the wrong way Braz, not having a go at you personally (or anybody else), but...

I keep seeing this 8-10" recommendation for double coil condensers on the forum. It really is not necessary. They are very efficient condensers.

A 6" (150 mm) double coil in 1/4" tubing, like the ones I make in my coil winding tutorial, has PLENTY of condensing capacity, more than enough for our purposes.

I have never tested one to its limits, as I don't have the heat source, but I would expect they can handle 5000 w safely. I can tell you that they handle 2400 w without blinking, using coolant flow rates waaaaay below the maximum possible. I am talking maybe 1/8 of the maximum. (Obviously this depends a bit on your water pressure. If you have very low pressure than adding a couple of extra inches is not unreasonable, just to be safe. But any standard town pressure should be plenty for a 6".)

That easily covers the power coming up a 2" reflux column (1200-1400 w), or even a 3" (2500-3000 w).

In virtually all situations anything longer than 6" is overkill and wasting precious column height, and condenser tubing. Bigger is not always better.

Only thing you need to watch is vapour escaping up the centre space of the inner coil. Just plug the top 2" of it with mesh/scrubber.

[Braz]

Please don't take this the wrong way Braz, not having a go at you personally (or anybody else), but...

Not at all. In fact I used the 8-10" number just because it is what I too have been reading on the forum. My coil is actually right at 7" and I have never been able to overpower it, even running straight water at 212F. So, I expect you are right, 6" is plenty (in more ways than one. I hope.)

[hoody]

How about using a cold finger?

[lacedspirits]

Alright, this is directed at Hookline.
I know you do a damn fine job making condensers and could probably wrap one in your sleep. I'm sticking with your 6 inch recommendation and am ready to wrap one tonight. I'm assuming since you have so much experience you would know how long of a piece of 1/4" copper I need to cut off the spool. Do you think 10' would be enough or am I looking at something around 20"???
Your experience would be greatly appreciated.
ls

[HookLine]

I use 3 metres = 10'

It is in my tutorial.

[lacedspirits]

I use 3 metres = 10'

It is in my tutorial.

Do you prefer propane or MAPP for annealing?

[olddog]

You really need Mapp to get it red hot quickly, it hard with propane.



OD

[lacedspirits]

That's what I wanted to hear olddog. I was considering just buying a condenser from Hookline but really want the satisfaction and gain the skills from making my own. I went to the tool shop this morning and bought another 30 feet of 1/4 inch soft copper tubing. I ruined 10 foot of copper last night and will likely ruin 20-30 more feet before I get it right. As long as I get it right, that's all that matters to me. I could buy 100' of 1/4 copper for what it would cost Hookline to ship me one of his. I'm determined to make this still from the ground-up with my own 2 hands.
Thanks again for all your help,
ls

[olddog]

One of the tricks is to keep it coiled up, do not staighten it out as this work hardens it, if you are careful, you can wind 1/4"without having to anneal it, just wind a half turn at a time and keep it tight to the mandrel.


OD

[HookLine]

Do you prefer propane or MAPP for annealing?

MAPP is better, but propane will do the job. Using a bigger nozzle for propane helps.

[lacedspirits]

I just finished my first 2x coil and am quite pleased. I followed Hooklines' tutorial as best I could. I couldn't find any 5/16 and 1.25 stainless mandrels so I had to use 1/2 inch copper and 1.25 galvanized steel pipes. The inner coil flattened a bit and looks more like a copper ribbon than pipe. The outer coil turned out perfect. The first 10' I used salt and that didn't work for sh*t, I kept kinking it every 3 inches. Tonight I finally went down to the tool shop and found a spring bender set, some piping for mandrels, and some fresh flux. I plan on making 2-3 more until I get it perfect. I'll post picks as soon as it cools down and after I run a flow test to see what kind of litres/minute it puts out.
Again, thank you all for your help and support.

[HookLine]

The inner coil flattened a bit and looks more like a copper ribbon than pipe. The outer coil turned out perfect.

If you don't use filler in the tube (and I don't), then the inner coil always flattens a bit. It is not a problem.

Congrats for your success.

[commonsense]

Don't do like I did I got so hung up on making a perfect coil that I lost site of why I stated the project, just start fermenting and get that thing up and runnin