Single Large Bubble Caps vs Multiple Smaller Bubble Caps

[WTDist]

Thought i would start this post for people deciding on single or multiple bubble caps. Dont even know if im posting it in the right location but this seems right. If anyone has any input or corrections to my sums feel welcome to add to this. Ive looked before and didnt find much on this so this may help others. This is just my findings along my travels here at Aussie Distiller and may help influence someones bubble plate design :handgestures-thumbupleft:

I was thinking about the large single bubble caps and multiple smaller bubble cap methods and wondering about their benefits...

I'm no expert on still making but in my short experience it seems like the multiple smaller bubble caps might be the way to go to increase ABV. When i was working out the area of my shotgun condenser i found that 2 1/4" tubes combined had the same perimeter as a single 1/2" tube but half the area.

Ive also read somewhere and i may be wrong, but what i read was the thinner the slots and with more slots in the bubble cap they will produce a higher ABV, more smaller bubble pretty much.

So in a 4" still if i were to have a single 2" bubble cap then this cap would have 159.6mm perimeter with small slots. the area is 2026.8mm^2
If i were to have 2 1" caps then the combined perimeter would be 159.6mm and the combined area would be 1013.4mm^2 which is half of the 2" cap

The area in the column after the bubble caps are taken away would be for a 2" 6080.5mm^2 making the average diameter of the column (once taking out the cap area) 87.98mm (4" is 101.6mm)
and for say 2 1" bubble caps the column area would be 7093.9mm^2 making the diameter 95.04mm
Im wondering if 7mm is much in diameter to increase speed, probably not but maybe it could be :think:

so...
If there were 4 1" then the area left would be 6080.5mm^2, the same as a single 2" cap but the perimeter of the 4 caps would be 319.19mm twice that of the 2" cap
So
if you do 4 1" caps instead of 1 2" cap then you have twice the amount of slots with the same area being consumed with the 4 bubble caps as the single 2".


Im Thinking that smaller bubble caps may give a higher ABV and with no loss to take off speed. And a single bubble cap may be easier to solder up or less work but have less ABV.

I have not run a bubble cap column yet so maybe the difference between single or multiple caps in a 4" still is zip to none and this doesn't matter. but maybe it does...

[Magnus]

You've done the math, interesting read m8. I'm still trying to work out what my next build will be. Think ill wait and see the results of your single bubble cap with interest.

On a side note my glass of bubbles is looking and tasting real well..

[dogbreath vodka]

Thanks for the thread WTD

Maybe one is better than the other

Or maybe - like all theories the proof is always in the practical applications.

This is the results from a 6" column with 4 x 3" single bubble caps

DSCN3973 (Copy).JPG

This is the results from a 6" column with 3 x 3" single bubble caps and a thumper (glass section on a carter head)

DSCN3265.JPG

This is the results from a 4" column with 5 x 2" single bubble caps

95% (Copy).JPG

What's my point?
You can pull azeo from any good still.
It not only depends on the still, it depends on the operator and what you feed the still (the wash)
It's all part of the hobby and we never stop learning. :handgestures-thumbupleft:

The advantage of one over the other?
I don't really see one.
Both multiple caps and single caps perform pretty damn fine. :D :handgestures-thumbupleft:

Just need to get in and give it a go with whatever you decide on.


As far as I can tell (correct me if I'm wrong here Mac), the only reason Mac went into the multi caps is they fit every still, from a 2" up to the 8".
One design - just keep adding extra caps to suit the size of the plate being used.
Ordering more of the same product = lower prices
So all his customers get a better deal. :handgestures-thumbupleft:
Having a one cap fits all saves on confusion as well.

That's clever designing.

[woodduck]

I read somewhere that mac recons on our small scale hobby rigs there's no real benifits to any perticular type of plates, be it, single, multi or perf. I guess if you look at the pro himself, he uses multi caps so there might be something in that not sure.

I think it is personal preference more than anything. Single caps would definitely be easier to build but i recon multi caps looks cool. Just my take on it.

[WTDist]

Excellent info DBV, the sort i like to hear.

I thought as much also with small rigs woodduck, i figured the difference would be zip for a 4". Just wasnt sure.

I plan on making a 6" in the future and im on the fence with single or multiple caps. What L per hour can a decent 6" achieve? with those ABV's DBV
EDIT: im looking to maximise my take off rate to save time for family etc. Kids can demand a lot of time 8-}

[dogbreath vodka]

When I run a 70-75 ltr boiler fill with a 12-13% wash
Can have that through in about 4.5-5hrs from start of the foreshots to final tails at 20%ABV
I tend to run slow.
So you could conceivably run at maybe 6+ltrs an hour, but I tend to keep it around the 3ltrs
Effectively I do a spirit run every time.
That way I end up with a very clean product as I will do three runs and cut out the heads.
Then those three runs are watered down to 40% and put through again for the final run.


There are a lot of factors involved.
What the wash is and the ABV of the wash.
Are you looking for a neutral, a flavoured spirit or a gin/flavoured vodka.

There are so many things you can do and experimenting is half the fun. :D :handgestures-thumbupleft:
If you did a stripping run, I can see it being over in 3.5 - 4hrs from light up to closing it down.

I might add as a safety precaution.
If you intend using a 6" column, I'd go electric. . . . it minimises possible kaboom/fire issues.

[WTDist]

sweat, ill be doing flavor runs with the occasional feints or vodka run.
Ill always go electric :handgestures-thumbupleft:

[dogbreath vodka]

Don't take my figures as gospel as it's been some time since I did a run and checked the flow rate.

Seem to remember somewhere that I was changing jars every 9 minutes
Each jar containing about 600- 650ml Which adds up to about 4.5ltrs an hour.
It wasn't a big deal to me (the take off rate) I was more interested in getting a decent product at whatever rate it was.

It definitely was/is faster than running a 4" and a 50ltr boiler.

A 6" is the ultimate hobby still for me.
It gives you the options of running a lower ABV wash and with a small boiler (80ltrs) and is quick, no matter what ABV wash you run.

Currently I am doing a 6% UJ wash as an experiment.
It distills cleaner with less heads or tails.
BUT the hearts at 95% is not a lot.
See this thread where I explained what I was doing.
Vodka/neutral thread