Thermometers?

[BoomTown]

Building a Boka, and have to buy thermometers to monitor column, and output temperature. Anyone have a recommendation for what works best and whet I can get it?

[still_stirrin]

Here’s a start:
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[NZChris]

Don’t use anything that switches itself off.

[Demy]

I use a simple alcohol thermometer, I also have digital thermometers but they are self-out if you don't touch something after a few minutes.

[Yummyrum]

It must read tenths of a degree or its pointless in a Boka Iff’n you are going to deduct anything from watching it.

Watch it but don’t take any notice of it .... its placement and accuracy will effect the reading .
Out of curiousity , I run one in my VM last weekend fir the first time in ages . It ran at 77.8°C for the whole hearts .
If I was to base that on Boiling points , I was taking heads for the whole run . It was well into tails before it read Ethanol boil point of 78.3°C
I was tasting tails starting to appear before the temp started to rise by 0.1°C . It was me that called tails , not the thermometer.

I agree that the auto shut off is annoying but all my thermometers have that function . If I want to know what the temp is, I turn it on .

[Saltbush Bill]

: Buy one of the ones used on the little commercial availabley t500 reflux stills.
Most HBS,s stock them as a replacement part.
I've used one for years on my 3 inch bona.
They don't turn them selves of and are accurate enough for what you need.
They also have a a foot or more of cable between temp probe/ sensor and the readout screen.
I've always found mine to indicate the onset of tails perfectly.
As soon as temp changes by 00.01c you know they are not far away.

[StillerBoy]

Out of curiousity , I run one in my VM last weekend fir the first time in ages . It ran at 77.8°C for the whole hearts .
If I was to base that on Boiling points , I was taking heads for the whole run . It was well into tails before it read Ethanol boil point of 78.3°C

I run using temp at the base of column, and at the top of the packing..

Temp probe reading are just indicators, not meant to read boiling points, due in large part to the small volume of vapors in the path..

In the example about of 77.8*C for the whole hearts.. that was a true indicator of the body section, per that unit setup.. once the temp changed a .1 tenth of a degree or in the case of 77.8, it changed to 77.9*C, that was the indicator that tails were starting.. by 78.3*C, that would of indicated right into the tails.. at 77.8 I would have started to compress the early tails a bit..

Also buy LED meter which are able to read in both F or C.. as the F reading is much more precise..

Mars

[Andrew_90]

Out of curiousity , I run one in my VM last weekend fir the first time in ages . It ran at 77.8°C for the whole hearts .

What is the adjusted BP of Ethanol for your specific altitude?

[Winnipeg204]

: Buy one of the ones used on the little commercial availabley t500 reflux stills.
Most HBS,s stock them as a replacement part.
I've used one for years on my 3 inch bona.
They don't turn them selves of and are accurate enough for what you need.
They also have a a foot or more of cable between temp probe/ sensor and the readout screen.
I've always found mine to indicate the onset of tails perfectly.
As soon as temp changes by 00.01c you know they are not far away.

I have a t500 and the thermometers are $30 at a local store and similiar price online anywhere. Aliexpress I ordered 4 of them and they are exact same functionally yet $3 a piece. Depends on how long you can wait. I will use a $3 replacement if my t500 temp gauge ever stops working.

[Tropic]

Watch it but don’t take any notice of it .... its placement and accuracy will effect the reading .
Out of curiousity , I run one in my VM last weekend fir the first time in ages . It ran at 77.8°C for the whole hearts .
If I was to base that on Boiling points , I was taking heads for the whole run . It was well into tails before it read Ethanol boil point of 78.3°C
I was tasting tails starting to appear before the temp started to rise by 0.1°C . It was me that called tails , not the thermometer.

I just bought more than ten 12v thermometers (10kOhm NPC) from Aliexpress. The thermometers seem to be accurate to +/- 2 degrees C. So I'll probably need to get some trimpots to add to the thermistor cables to calibrate them since these are non-adjustable gauges.
Also, depending on their placement, thermometers can measure the hot vapour going up, the cooler condensate going down and maybe some column wall if the probe is close enough to conduct it.

My build is a completely over-the-top measuring still where the thermometers are placed through the column into the packing spaced every 16cm over a 128cm long insulated column. Here's the first results of a 8% spirit run recorded once the boiler hit 70C, then measured each 5 minutes until I got bored. Initial reflux was 50% then pushed up to 80% after 9:15 which is why the top 2 gauges drop after 9:15 - they are getting cold condensate on them.
Read the graph right to left in time and each 'section' is a thermometer at the base, 8cm above the base, 24cm, 40cm, etc.

[BoomTown]

I’m seeing several recommended thermometers that have cables and probes. How does that work? How are the sensors installed?

[boomstick]

As soon as temp changes by 00.01c you know they are not far away.

Do you happen to have a link for that model. Havent seen anything that is reliable lower than 0.1C

[Saltbush Bill]

My mistake they do only read 00.1 .... close enough for what we need though.
Google T500 thermometer finds plenty of them.

[boomstick]

My mistake they do only read 00.1 .... close enough for what we need though.
Google T500 thermometer finds plenty of them.

Ah thanks. That extra digit would have been cool to see.

[NZChris]

The extra digit wouldn't be useful. For my Bokakob, I wait until the temperature is well settled, then use a 0.2C rise to either decide to shut down, or automate the shutdown. Anything collected after the rise is only good for tossing under the lemon tree.

[boomstick]

The extra digit wouldn't be useful. For my Bokakob, I wait until the temperature is well settled, then use a 0.2C rise to either decide to shut down, or automate the shutdown. Anything collected after the rise is only good for tossing under the lemon tree.

But for the datadriven curious mind it would be nice indeed.

[Saltbush Bill]

But for the datadriven curious mind it would be nice indeed.

Boomstick just something i noticed over the last 9 - 10 years of forums....maybe pay attention over the time you spend here to how long data driven folk stay in this hobby.......few seem to last very long.

[bunny]

BoomTown-
This is not a "Boka" per say, but is an LM head that I screw to the top of my spp column.

I scrounged up 4 of these Taylor 9867FDA digital thermometers from Amazon, Ebay, and COSTCO.
They turn on/off only by opening and closing the probe. They will run for days straight on the two AAA batteries.

This one is stuffed on top of my stripper.

They are easy to calibrate in distilled water vapor if you know your barometric pressure. I live practically next door to the Hillsboro, OR airport at almost the same altitude. The adjustments are in 1/2 degree increments, so I wait till the Barometer reads 29.92(212 degrees) or about 30.55 (about 213 degrees). This ends up fairly accurate (relative to my budget).

Bad news is they may be out of production. I've seen them offered on EBAY for 15-70 USD

$23

$34.95+$8.50 shipping

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$56.51

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