see saw design

[metalmickey]

Hi Any bight sparks out there to think this one out for me...?


Ive missed the cut on the 50ml acetone/methanol collection a couple of times so i thought of a method of collecting it without being present, but im not sure how to biuld it.

Its essentially a see-saw with a cup at one end and a slope on the other.

when the bucket fills up it will fall away from the alcohol drip stream (see saw or ferris wheel) to be replaced by the slope at the other end of the contraption, diverting the flow into my collection vessel.

anyone seen such a device or made somethiong similar? or am i trying to solve a problem that doesnt exist?

MM

[Normski]

Im not sure leaving a still alone is a good Idea, At least wait until you know its not blocked and some spirit is flowing.

[Almanac]

I like the idea but no clue how you'd go about it but I'll be very interested if anyone can come up with a solution.

Come on the inventors - I can hear the brain cogs whirring from here.

AM

[Capt-Cudellez]

Have to agree that leaving the still unattended is a risky idea, that aside are you taking about missing the point where you would swap over to the collection vessel - so instead of 50ml you have a few hundred mls that you would rather not throw out?

If that is the case, why not just keep it and chuck it in with the next run and make that cut over properly on the second run.

[Almanac]

See! no panic! Everything is solvable. Don't worry - be happy!

Don't leave your still unattended for long periods. Having said that I don't believe it's necessary to stand beside it on a stripping run.

When I set my Airstill up for stripping I set the plug-in timer for 3.5 hours and let it run. I often set this to start at 3.30am so that it's finished at 7am when I will be up and about, then I can empty it and put on another 4Lt and get the max possible done in a single day.

A spirit run is a little different. From my records I can predict, with reasonable accuracy, the time of each cut and I use the alarm on my mobile to tell me when to go to the still to change collection vessels. Even though I can predict the cuts with reasonable certainty I never take those cuts for granted and go to the still 10 minutes before I expect each cut.

Unlike a stripping run, I only do a spirit runs when I'm at home and available to regularly check the output. I keep a very close eye and nose on the distillate to make sure I get the end of the heads and keep the tails out of the main body.

Having said that - I can see the merit it automating the physical change over of collection vessels for the foreshots and heads.

For what it's worth I came up with a basic design the workings of which I have not tested but I believe it would work with a little tweaking!

Parrot Draws.pdf

You'd think I had nothing better to do!

AM

[Capt-Cudellez]

I had in my head that MM was using a T500 - I see where you are coming from talking about using an air still.

When I'm doing a strip and chucking 3Kw at it, it produces between 10-12ltrs of distillate in a little over 2 hours - if I was to pop a cooling hose the room would be full of vapour in no time so I'd rather sit by the still, reading a book or going on-line with the laptop. It's just not worth the risk for me, but we all make out own choices.

[metalmickey]

Wow thats a great design. If the collection vessel is wide enough it wouldnt matter if the drip tube moved a few cm to accomadate the movement of the foreshots cup

Nice one and yes im using an airstill.

the starting point for the still output is somewhere around 70 mins+ but it depends on the temp of the wash. As im not particularly organised i often forget to set the timer on the cooker to remind me to return and remove the shot glass in the funnel.

What times are you expecing the cuts and how much do you collect of each?

MM

[YHB]

I like that, a lot.

Slightly off topic but somewhat related.

I was talking to a guy in the local HBS, who was describing his modus operandi to speed up the stripping.

He has a dedicated stainless steel electric kettle that he uses to preheat his wash. He fills the kettle three times and heats the wash to a temperature of just less than the temperature that things start to happen and then adds it to the airstill. When the airstill is full with hot wash he turns it on.

Is this a common practice, does it / would it save time? I have never seen it mentioned here, is there a reason?

Just Curious.

[Almanac]

What I posted earlier can only be done with an Airstill.

You can bet your ass I won't be leaving my new 50Lt still alone when it's running. Once you get into serious equipment you got to get serious about safety too!

MM I've attached a chart of a recent Airstill operation which I recorded for the purpose of posting.

Output Diagram.pdf

there's a cat among the pigeons!

Note: the strip in this example had tails @ 30% ABV added to boost output.

I copied mozr's chart but included results from my full run and if your output falls anywhere between the two examples you're doing alright. The difference between mozr's figures and mine is simply due to different methods and shouldn't be interpreted as one method being better than the other - it's just different strokes!

AM

[Normski]

-----------------------------------------

I like that, a lot.

Slightly off topic but somewhat related.

I was talking to a guy in the local HBS, who was describing his modus operandi to speed up the stripping.

He has a dedicated stainless steel electric kettle that he uses to preheat his wash. He fills the kettle three times and heats the wash to a temperature of just less than the temperature that things start to happen and then adds it to the airstill. When the airstill is full with hot wash he turns it on.

Is this a common practice, does it / would it save time? I have never seen it mentioned here, is there a reason?

----------------------------------------------
Hi YHB
Not sure its common But its what I've always done. It saves a lot of time. I do this with both the stripping and spirit runs. I use a 1.7L kettle and only put 1L in. Heat it up. Tip it in the boiler. When full I give it a degas. Turn still on. It usally starts to drip in 10 to 15mins. Fastest I've had was 8 mins.
Quick enough Not to have to leave the still alone to collect the foreshots etc.

Norm

[metalmickey]

i might give that kettle method a try but how doyou stop it boiling at 80 rather than 100? im assuming the bimetal strip will bend at 100 degrees truning off the kettle, otherwise youd be bioling off the alcohol.

although (thinking while trying) any methanol would boil off at 65 degrees so as soon as the kettle started boiling then you could turn it off...although there is virtually no methanol in a sugar wash.

Any thoughts?

MM

[Capt-Cudellez]

If it was me, I wouldn't let it get up to boiling - maybe just leave the lid open and use a thermometer to check when its getting up there, then switch off at the wall.
Or to do it oldschool - dip your finger into it 3 times in quick succession if you can do it 3 times but don't want to do it a fourth, its probably in the low-mid 60's. I read that on another site and tried it out, it does seem to work - but I guess folks tolerances could be different.

[Normski]

Even if you heat it more than, lets say 60, as soon as you chuck it into the boiler it will cool a bit. I dont worry to much, just heat it and chuck it in. It has worked every time. It still needs a bit of heating in the boiler before it will start to flow. But it can be quite quick if you want it to be.
I did a test yesterday. just to see what would happen if it was boiled. I got it to start dripping spirit in 2 mins. I was a bit surprised and had to feel it betweem my fingers and smell it. It was spirit. Now that is quick, Probably too quick, but I had to see if there were any problems and there wern't. The run went as normal. Remember this is just to save the 320w boiler some time in getting up to temp. I recon its also saving about an hour of the life of the boiler element too, every run. And as a cheapo kettle is about £4 in asda/tesco etc it makes sence to me. >:D

[metalmickey]

anthing that will cut the run by an hour is a good thing.

mm

and thanks for the tips.. this sort of info should be in a "how to " section.

[Normski]

Hi MM

Give it a try, and then please come back to your post and let us know what you think.

Norm