Why not glass?

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Re: Why not glass?

Postby spencoid » Wed Aug 02, 2017 10:30 am

i missed the part of your posting with the actual calculations. i see that you had not missed my idea about the distillate cooling the teflon piece. a couple of points though. i think that the distillate is cooler than just 2 C below boiling when it hits the teflon. it also sits there because the draining was not complete (it is better now but still not perfect) so it could also be evaporating to some extent and absorbing more energy this way. also the teflon piece loses some heat to the outside air but i think teflon is not a great conductor of heat and this is probably minimal.

one thing i forgot to mention is that in an attempt to keep liquid from wetting the bots, i made the lower end of the teflon fairly steeply conical. compared to the original flat piece, the surface is maybe twice what it was. if i run the still pretty fast it looks like a lot of condensation is occurring on the glass walls as well as the teflon piece but of course it is difficult to see if there really is distillate running down the feed tube. i hope the new setup will allow me to see what is really going on.

i think i also forgot to answer the question about how the reflux condenser is controlled. the cooling water is pumped from the heat exchanger to a wye where it goes to both the main condenser and the reflux condenser. to get to the reflux condenser it goes through a solenoid valve which also has a needle valve in it. so i can control the amount of cooling water with both the needle valve and under microcontroller control. the microcontroller has several counters and timers running. one counter is incremented 10 times a second, one is incremented once per second. the faster counter is used to pulse width modulate the heater and the once per second to PWM the cooling water to the reflux condenser. this is so the valve does not open and close excessively. i definitely can see a difference in the reflux when i change the duty cycle or open the needle valve more or less. my guess is that if the new setup works better and i am not condensing off the teflon piece of spilling back through the vapor tube that the reflux condense will be too small.

i might try running the still with just water as a test if i have time today.
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Re: Why not glass?

Postby spencoid » Wed Aug 02, 2017 1:32 pm

i ran the still with just water as a test. it now seems there is not as much condensation on the teflon piece. there is really little but there is a little on the glass tubing near the top. if i figure out how to insulate this section it might improve.

definitely do not have a big enough reflux condenser after downsizing it over and over so i made much larger one which i will install before the next run. i can get what looks like 50% reflux with the current coil at about a 30% heating rate which should be about 1500 watts. only guessing, did not measure.
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Re: Why not glass?

Postby spencoid » Sun Aug 06, 2017 4:26 pm

i ran the still today for a while. the teflon cone no longer condenses vapor. i am getting a lot of flavor from the bots because they are in the vapor path and not getting wet now. the larger reflux condenser is close to big enough now. i can get close to 100% reflux now as long as i have the heater running at 1000 watts. i can run the still at 1500 watts in normal operation with the duty cycle of the reflux condenser set at 60%. my distillate is coming off at about 186 proof. when i dilute it to something reasonable like 100 proof, it actually tastes quite good.

still a lot of details to work out but i am finally getting there.
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Re: Why not glass?

Postby skow69 » Tue Aug 08, 2017 2:04 pm

Congratulations, spen. I'm happy to hear you are getting some drinkables. What are you charging the still with? Wash or neutral or?

To me, it still kinda feels like going through the glovebox to get into the trunk, but don't let that stop you. No doubt you will continue to improve the process as time goes on. Let us know how it goes.
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Re: Why not glass?

Postby spencoid » Tue Aug 08, 2017 4:54 pm

using fermented sugar. some day i might try something like potatoes or cattail roots. a friend would love to have me remove a ton or so of cattail from her pond but i think i am too old for that kind of work.

not sure about the analogy? i can actually get some really good gin out of the still and some not as good after that. i dump the first 250 ml for fear of methanol. run the still on full reflux at relatively low head temp and then run it at that temp for the first 250 ml. then i run it at a higher temp limit (but of course it will only heat to whatever there is to boil in the boiler. the limit shuts the still down at the set point so i don't have to watch it the whole time. preheat mode is also really useful to avoid watching. i think i got 48 ounces of strong good gin and about 36 of not as good gin and then about 16 ounces of gin good enough for gin and tonics if you are not that fussy. i am making my own tonic and it has a lot of flavor so the gin is not as important but i will use the best for anyone who can tell the difference. the best gin is 184 proof and then next is about 170. the drinkable stuff is about 150. the reflux seems to be doing its job since i go pretty quickly from 150 proof ok stuff to weak nasty garbage tails without losing too much alcohol, i think. this was from a load of 10 gallons. i think i forgot to check the OG so i did not bother to try to determine the alcohol in the mash. next batch i will do a lot more measuring at every stage but i do think i am getting my value from 20 lbs of sugar.

my still may seem a little odd but i can get a reasonable amount of really good gin in one distillation without having to deal with a stripping run etc. once i figure out the best heating rate, reflux rate and temp cutoff for each phase, i can automate each phase without having to sit and watch. i can use measurements like the condenser output temp to moderate things like the heating rate. currently it is just used to shut down the still when it gets too hot or stops flowing.
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Re: Why not glass?

Postby skow69 » Sat Aug 12, 2017 4:40 am

So you're making gin in a single run from a sugarhead wash with no heads cut. Not the way I go about it, but if you like it, what the hay.

I get the feeling there is no point in trying to talk you out of automation. One of the cardinal rules here is to never leave a still unattended. Even if you are sure you have all the parameters covered, things can go south and end in disaster.

Some things require an investment of time, but once again, if you are satisfied with the result, so be it.
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Re: Why not glass?

Postby spencoid » Sat Aug 12, 2017 8:42 am

i am not sure what you mean by "no head cuts" i am definitely throwing away the first 250 ml of distillate from a 10 gallon sugarhead wash this is after running at full reflux for a half hour or so. i have to turn the heater down to about 20 % to be able to condense all the vapor with the reflux condenser.

when i no longer getting a strong distillate, i stop making gin and run the rest off (until i start getting mainly water) and put this in the next run. but i definitely throw away the heads, don't even want to keep it around but maybe i should save it for Tiki torch fuel?

what is he advantage of doing a stripping run first and other than dumping the heads in the stripping run, how much do you "strip"? do you run until you are getting water? then when i do the second distillation, how do i determine what dilution to use? i assume i would add just plain water.

i thought that the stripping run was to remove any off flavor stuff that might get through but i really do not have anything nasty. i have made on liter of 184 proof gin that several people have tasted and exclaim about how smooth it is and without aftertatste.

i decided to practice my TIG welding a little and made a couple of gin baskets to replace the tea balls i was using. i can now have about 3 times as much bots in the head and it takes up more of the vapor stream so it should really extract the flavors much better. i also did eliminate the condensing at the top of the column so no liquid is washing over the bots.

it is not very likely that i will ever leave the still truly unattended. so far i have found that minor adjustments to reflux setting and heater strength are needed as the condenser temp increases and as the boiling temp changes if i am to get the strongest stuff. i do not have enough water in the summer to use fresh "tap" water for cooling and int he summer it comes in really hot anyway. so i have to use an air cooled radiator and a limited amount of cooling water. at some point i will increase the size of the reservoir but at lest for now, the condenser does run warmer at the end of a run. i have a limit set at 50 C to shut off the still.

when the head temp reaches the target the heating stops and a beeper sounds. i stay close enough so i can hear the beeping and check back frequently. i have done some stupid risky things in the past and although i have never burned down a house, i have injured myself and have broken a few things but i think a lot less than some people. i am very careful about machines and dangerous substances like alcohol. i am pretty confident that my system is quite safe but certainly not safe enough for long term running without monitoring. i just don't want to sit there and watch the whole time.

if i can think of another safety device to add, i will. my last still had a mercury vapor thermal shut off right on the heater coil. if the boiler leaked or ran low it would shut off the heater and require manual reset. i would like to add something like that to the new still but access would be difficult unless i really get good at welding or maybe use one of the weldless bulkhead connectors to get the thermostat tube through.

i have a level tube that i monitor to be sure the heater is covered but nothing automatic. i should add a level sensing device, i guess. that can probably be done with a wire in the level gauge. there are reflective level sensors used in industry but that would require another hole and one that could withstand the hot alcohol would probably be very expensive.

any suggestions as to how to make the still safer would be appreciated. i am still trying to figure out something that would have warned me when the condenser section glass broke.
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Re: Why not glass?

Postby spencoid » Sat Aug 12, 2017 8:50 am

one other thing. i really like the last batch i made compared to previous stuff and even compared to mid priced commercial stuff but this is certainly not the end of the experimentation. i want to keep fiddling with processes and recepies and different sources for flavors. what i like about gin is the immediate feedback. no waiting for aging etc. i had not really thought about making gin until i tasted some made by a local small distillery. it was such a pleasure to sip their $45 (750 ml) bottle i thought i would take it as a challenge to try to make something similar. i have gotten close.

i do want to keep improving what i made and also the efficiency since i do not like to have more vats of stuff fermenting than necessary. so if i should do a stripping run or anything else to improve the yield and quality i am certainly open to suggestions.

i downloaded tons of info from the Aussie site but have not had time to read most of it. I am sure there are docs that would answer most of my questions but a simple summary about how to go about a multiple distillation gin making would be helpful.
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Re: Why not glass?

Postby raketemensch » Sat Aug 12, 2017 6:14 pm

What you’re calling “heads” is actually called “foreshots.” Yes, use them for fuel, or ant killer, or pour them out.

The next fraction after them is called Heads — they have a stronger alcohol “burn” to them, along with a fruitiness that is stronger than the rest of your product.

They also, however, are apparently the main cause of hangovers. The vast majority of us also remove these from the final product and throw them in the jar with that final fraction that you’re rerunning — which is commonly called Tails.

Foreshots, Heads, Hearts, Tails. Check out the Beginner’s Guide To Making Cuts thread, it can do more for your quality than most other things, especially at the beginning.
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Re: Why not glass?

Postby spencoid » Sat Aug 12, 2017 6:26 pm

can you please provide a link to Beginner’s Guide To Making Cuts thread. i can't find it by searching etc. if i do a full reflux for a half hour and then remove the first 250 ml from a 10 gallon sugar wash, would i be removing both the forshots and the heads?
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Re: Why not glass?

Postby spencoid » Sat Aug 12, 2017 6:50 pm

i found the following which is probably the thread recommended. it is highly informative. saved an offline copy so i can find it more easily the next time. i am getting some very drinkable stuff already so after digesting this and learning a little more about how to use the gin basket should produce something really good, eventually.

viewtopic.php?f=15&t=11640
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Re: Why not glass?

Postby raketemensch » Mon Aug 14, 2017 10:09 am

Awesome. One of the nice things about this hobby is that there’s always something else to learn, and more you can do for a better product.
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