Thread: Behmor max temps

The temp you're measuring with the heatsnob is environment temperature, not bean temp. Have a look at the image of the profile attached to this post http://coffeesnobs.com.au/home-roast...tml#post568241 - the pink line is ET while dark green is BT. You'll see the BT keeps rising where ET levels off.

Originally Posted by stevenc

I'm also interested in those steep temp drops that people post on cooling, with temps dropping from 200C to 20C in a minute or 2.

I get this by opening the door, taking the chaff tray out (careful, extremely hot) and blast a fan in.


20160331-ethiopia-yirg.jpg

Hello Steven,

I’ve been using a Behmor for about five years with reasonable results. Andlike you I’ve not seen incredibly high temperatures. Not 200. When I first gotmachine I did query this with Behmor butthe answer is the power feed to your house. Which I can tell you here there isabsolutely no problem.
I’m into HiFi and have a voltage monitor across my mains it’svery steady here at 238 V and I plug my Behmor short heavy grade electrical cable back to themains board. There is no loss there. I am very confident I get maximum Voltsand amperage.
One thing I do know if you lessen the amount of copy beansin your roaster this will bring up the heat significantly. I’ve worked out formyself and optimal amount of green beans in the roaster is 220 g. I roast inmanual mode bringing the beans up to 1^st crack as quickly aspossible and then controlling the heat from the using the other buttons todecrease the heat at any given point as I see how the beans are progressing allthe time that they have been in the Behmor.
I have been a little naughty and have been doing this for along time now and it is been working well for me and that is when I’m satisfiedwith the roaster that I’ve had cooling after which a few seconds pass I stopthe machine quickly grabbed the tumbler containing the beans and remove it fromthe Behmor after which I turn the callingcycle back on in the Behmor . I’m then quickly exiting the house with the beansand hands (picture me wearing some very sturdy gloves so I don’t burn myself) I’moutside now with ambient temperatures around about 20° or less at this time ayear 17° and I start shaking the tumbler. Benefits I found you slow the roastdown quickly and remove more of the husk from the beans. You have to really setyourself up well and ensure you can do this safely. It’s not a recommendedapproach by Behmor and they would advise against it.. but that’s what I do here.Sure there is a concern about decreasing Behmor life expectancy but I’m fairly confident itwon’t drastically shorten its life as I’ve already been doing for at least ayear now.
With 220 - 300 g of beans I would reach first crack in about9 ½ to 10 minutes SHB beans taking longer. If I’m using SHB I will lighten the beanload to 220 g.
If you do a cleaning cycle look at the temperatures that youwill get there and they’re starting to get right up there for me the highest I’veseen is 180°C so that’s what taught me that it was how much green matter is inyour Behmor
also when you’re in manual mode it is P5 that is giving youthe full element heat. So you would start off doing your usual roast hitting astart button then I would hurt P5 to bring the elements to maximum heat output.P4 being 75 and P3 being 50% heat output I’ve not used anything less.
For myself I never experienced any real joy using theprofiles so I found my way to using manual mode. And I think it’s all becauseyou’ve got to get that balance of the right amount of beans in your Behmor to beable to use the profiles at any given weight. But they’re not all beans are thesame. So I found it easier to use manual mode.
The more beans you use in your Behmor thetrick here it is to control where you want the beans to slow down and to stoproasting.
I would be really interested also to hear those getting 200°Ctemperatures and being able to drop the Behmor to 20°C within a minute - the little fanin the Behmor Hmm It would be most interesting to hear how that isachieved.
The only time I’ve had my machine shut down was not givingthe Behmor enough time to rest after a roast and thendoing another. Anyway I find the Behmor tooperate better with less beans. HoweverI’m surprised that 145°C is where youreach first crack whilst not a great deal more in my Behmor itwould be nothing less than 154 -160 most of my roasting is taking place at 160degrees C
also there is something else I noticed compared to you, I cannot preheat my Behmor to 100° C same as you, if I let my Behmor get to anything like 75°C it would fail to start I would have to wait for it to cool. I use to pre-heathowever using less coffee beans that’s a practice I’ve stopped doing.

Hello Agrajag,

I've not seen the HeatSnob unit can you point me to information looks really interesting

Thanks
John

Originally Posted by nzgreenbean

I've not seen the HeatSnob unit can you point me to information looks really interesting

Available here: CoffeeSnobs - BeanBay - Other Stuff - HeatSnob Temperature Data Logger

More info here: http://coffeesnobs.com.au/home-roast...-software.html

By the way the beans certainly would be getting > 200°C in the behmor otherwise you wouldn't be roasting your beans. The temps you're seeing are lower because of where they are being measured.

Originally Posted by stevenc

After reading through dozens of posts I'm still unsure about the max temps I should be expecting in my Behmor 1600 plus. I've happily done over 100 roasts over the past few years, with (usually) great results, at least to my taste.

But having recently added HeatSnob unit and using the new features of the Behmor plus panel (A and B temps), I'm wondering if I could be doing things better. I know that the results in the cup are much important than a roast graph but it has me wondering...

In particular, I always seem to be hitting first crack at around the 145C mark. From that point ETs don't rise much at all and second crack is usually at the same or only 1 or 2 degrees higher. This has been consistent on over more than 20 roasts of Ethiopian Gambella using a 400 g load on P3, D settings. I tend to preheat to around 100 C before loading.

I've noticed lots of roasters in the forums using Behmors reporting steep temp rises to over 200C.

There is no way that my Behmor will reach 200C unless I am missing some trick. The few times that I have tried a faster temp rise with a P1 manual setting it has auto shutdown to cooling cycle at around 170C.

I'm also interested in those steep temp drops that people post on cooling, with temps dropping from 200C to 20C in a minute or 2. In my Behmor, with cooling cycle and door open, it takes the full 13 minutes of cooling for the temp to go from 140 back to 25 C or thereabouts.

The temp logs are a great but for me they are raising more questions than answers. Perhaps I can get some here.

Thanks,

StevenC

Just to clarify Steven - which temp readings are you referring to? 'B' readings on the Behmor? 'nzgreenbean' pretty much covered all variables in the two posts above and I use my Behmor similarly. For example I've got some Mexican SHBs at the moment and I've had to drop the quantity as the first attempt didn't get hot enough even on P1 auto and P5 manual after the fan started. Most of the time I'm roasting between 250 and 350g batches as I find this is sort of a sweet spot. 400g seems to be too much for all except some softer Brazilians or the like.

So the 140degC you mention must be the 'B' temp reading. Is that right? If so then you're right that it won't go much above 140. In fact it'll probably shut down if it went too much higher although I'm not sure exactly what level the safety shut off is set at. 'A' temp readings will go much higher later in the roast once the fan has been running for a few minutes. I don't use 'A' readings as they don't really seem of too much use to me as they're not a true environmental temp. So until I get myself a Heatsnob (hopefully soon) I just use 'B' readings to 'profile' a roast and make adjustments or repeat a successful roast. Max 'B' temps for me are usually around the 146degC mark.

And yeah there's no way you'll get fast cooling by leaving the drum in the machine. Within a minute or so of starting the cooling process I whip the tray and drum out, tip the beans into a colander and sit them on top of a fan to cool. I always make sure I hit cool on the Behmor again to let it go through the motions of a proper cooling cycle, but I don't bother putting the drum or tray back in. I reckon I'm getting better results in the cup since I started doing this.

Can't speak for the new heatsnobs, but here's an example of the temp readings I get using a pair of the older Victor DMM's.
Eth. Harrar, 180g charge, P3B, with manual override to 75% power at 11:45, and 25% power at 13:30. Door open on cool + fan.
Red = internal, Blue = exhaust.
Eth.HarrarP3BSample.png

This post shows you where I've mounted the bead probes.
http://coffeesnobs.com.au/home-roast...tml#post565133

Thanks Agrajag,

I understand the BT keeps rising while the ET falls off. What I'm curious about is that others, like this example, are reaching much higher ET than me. This example shows ET at around 170C. My Behmor throws to the cooling cycle with Err2 at an ET of 165C or thereabouts.

I am measuring ET with heat snob unit placed according to the classic CS template. For the record, it measures pretty much exactly the same as the Bemhor B thermistor readings.

Or are the >200C temps I have been seeing in other posts BT, instead of ET? I thought I was comparing apples with apples but maybe I've misread the data.

Cheers,

Steven

Thanks NZgreenbean,

I will try smaller batches and see if this helps. Although even with an empty roaster on a clean cycle I'm not seeing ET reaching these high temps, using either the B thermistor or the heat snob probe.

Pretty sure my voltage is fine as I used to monitor it when we had some power issues. Is usually a solid 240 at the outlet.

Using the heat snob probe I do know that I can reach 95C in a preheat no problems. Not sure where the cutoff point is, but it's not time dependent as I would be well past the 1:45 'limit' in the manual.

Cheers,

Steven

That's a decent temp plunge. Might try that technique. I know that the really steep temp drops are achieved by removing the beans to a cooling unit of some sort but then how are the temperatures being logged? Good to know you can improve a lot still in situ in the Behmor.

Thanks,

Steven

Originally Posted by pcf1978

Can't speak for the new heatsnobs, but here's an example of the temp readings I get using a pair of the older Victor DMM's.
Eth. Harrar, 180g charge, P3B, with manual override to 75% power at 11:45, and 25% power at 13:30. Door open on cool + fan.
Red = internal, Blue = exhaust.
Eth.HarrarP3BSample.png

This post shows you where I've mounted the bead probes.
http://coffeesnobs.com.au/home-roast...tml#post565133

I am using the classic CS HeatSnob probe placement which is the sames as your probe placement with the older DMM. So why are you getting ETs of 230C when I am never hitting higher than 170C without an Err2 shutdown.

Steven

Originally Posted by stevenc

So why are you getting ETs of 230C when I am never hitting higher than 170C without an Err2 shutdown.

Steven

Dunno

What does your heatsnob/probe measure in boiling water?
Could try another probe or even a bead type?

I wouldn't get too hung up on the DMM temperatures as long as they're fairly consistent from roast to roast. If you are hitting first crack then your environment temperature is reaching 200C and beyond. For what it's worth my DMM readings look nothing like the built-in A/B readings on the Behmor display, which always seem to be much lower.

The exhaust temp will be higher than internal chamber temp due to afterburner, that's my understanding.

I have done a couple of of roasts with bean temp and I also noted down the A and B temps (need to try and plot them back in to the profile). I will post these up once I figure out how.

The err2 seems to kick in at B temp of 166. Is that your experience?

Cheers

Here it is.

Main temp is bean mass temp, measured with bead type sensor.

I manually added the A temp and B temp into the CSV (is there a way of inputting temps manually in the roast other than the air and heat sliders?)

A and B temps were logged every 30 seconds. B maxed out at 164 degrees C at 12m30s.

Ambient temp was 25.3, bean was Kenya AAA Bold, 411g green, resulted in 340g roasted.

Also is there a way of making the template colour again to enable export to JPG?

Cheers

Kenya AAA Bold.JPG

Nice work artman! If you don't mind me asking, how have you setup your bean mass probe? Looks to be nice and smooth.

Originally Posted by artman

The exhaust temp will be higher than internal chamber temp due to afterburner, that's my understanding.

I have done a couple of of roasts with bean temp and I also noted down the A and B temps (need to try and plot them back in to the profile). I will post these up once I figure out how.

The err2 seems to kick in at B temp of 166. Is that your experience?

Cheers

Just did a test on empty roaster running manual P5 to get the temp up and it throws an Err2 at a B temp of 163 on the nail. That is the temp I thought it hit last time I got an Err2 (sadly full of beans that time!). Well at least I know what B temp to stay under now. Stupidly managed to close the RM program so lost the HeatSnob probe temp but it was slightly under that - seems to run 10C below the Behmor B value.

I'm guessing with the graph you just posted of the Kenya beans you were on an auto profile so the Behmor was keeping itself under the cutoff temp of 165 or so? (Minor differences in Err2 temp due to variations due to different voltages etc I suppose..)

Cheers

Originally Posted by artman

The exhaust temp will be higher than internal chamber temp due to afterburner, that's my understanding.

I have done a couple of of roasts with bean temp and I also noted down the A and B temps (need to try and plot them back in to the profile). I will post these up once I figure out how.

The err2 seems to kick in at B temp of 166. Is that your experience?

Cheers

Correction - user error at my end. You are quite right. B 166 seems to be the magic number to trigger an err2. A number to watch out for!

Cheers

Steven

Originally Posted by Agrajag

...the beans certainly would be getting > 200°C in the behmor otherwise you wouldn't be roasting your beans. The temps you're seeing are lower because of where they are being measured.

Give yourself an elephant stamp for an excellent answer!

The temperature measured means nothing except it was a temperature measured.
It won't translate to another person's setup or even the same type of roaster. There are so many variables that can change the expected number.

DON'T GET HUNG-UP ON SOMEONE ELSE'S NUMBERS

Okay, now that's out of the way...

I always seem to be hitting first crack at around the 145C mark. From that point ETs don't rise much at all and second crack is usually at the same or only 1 or 2 degrees higher.

Perfect. Shows consistency in what you are doing, it really doesn't matter if you see 45C, 145C or 245C... the number you see makes sense for your roaster and conditions and if you can repeat it (as you can) then you are well on the way to being able to make fine adjustments and taste the differences.

I'll let you into a secret, Arabica beans have a built-in thermostat that cracks at 196C.
Yep, that's right, when you hear first crack the bean temperature is 196C so you can adjust to "real" numbers using the bean as a guide.

Luckily we have that covered in Roast Monitor too. If you make the following changes to your preferences.txt file you will calibrate your temperatures with the actual temperature of the bean (regardless of where you have the probe).

Change this:

Code:

# Meter calibration factors.
meterAdjustMults=1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

To this:

Code:

# Meter calibration factors.
meterAdjustMults=1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=51.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

or better still to this:

Code:

# Meter calibration factors.
meterAdjustMults=1.3 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

The first one will add 51C to the read temperature, it will make low temperature readings wrong but it will be calibrated accurate at first crack.

The last one will make all readings on the primary HeatSnob 30% higher and will be at its most accurate at first crack too.

Make sense?

You can find the setting file at:
My Documents\CoffeeSnobs\Preferences.txt
Just open it with Notepad, make the edit and save it.

Re: Artmans questions... please post the specific Roast Monitor questions in the Roast Monitor thread, I would rather reply to them there so others benefit from the answers instead of them getting buried here.
http://coffeesnobs.com.au/home-roast...-software.html

Originally Posted by Andy

Give yourself an elephant stamp for an excellent answer!

The temperature measured means nothing except it was a temperature measured.
It won't translate to another person's setup or even the same type of roaster. There are so many variables that can change the expected number.

DON'T GET HUNG-UP ON SOMEONE ELSE'S NUMBERS

Okay, now that's out of the way...



Perfect. Shows consistency in what you are doing, it really doesn't matter if you see 45C, 145C or 245C... the number you see makes sense for your roaster and conditions and if you can repeat it (as you can) then you are well on the way to being able to make fine adjustments and taste the differences.

I'll let you into a secret, Arabica beans have a built-in thermostat that cracks at 196C.
Yep, that's right, when you hear first crack the bean temperature is 196C so you can adjust to "real" numbers using the bean as a guide.

Luckily we have that covered in Roast Monitor too. If you make the following changes to your preferences.txt file you will calibrate your temperatures with the actual temperature of the bean (regardless of where you have the probe).

Change this:

Code:

# Meter calibration factors.
meterAdjustMults=1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

To this:

Code:

# Meter calibration factors.
meterAdjustMults=1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=51.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

or better still to this:

Code:

# Meter calibration factors.
meterAdjustMults=1.3 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0
meterAdjustAdds=0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

The first one will add 51C to the read temperature, it will make low temperature readings wrong but it will be calibrated accurate at first crack.

The last one will make all readings on the primary HeatSnob 30% higher and will be at its most accurate at first crack too.

Make sense?

You can find the setting file at:
My Documents\CoffeeSnobs\Preferences.txt
Just open it with Notepad, make the edit and save it.

Re: Artmans questions... please post the specific Roast Monitor questions in the Roast Monitor thread, I would rather reply to them there so others benefit from the answers instead of them getting buried here.
http://coffeesnobs.com.au/home-roast...-software.html

Thanks Andy,

I understand that temps are a relative, not an absolute, measurement. Guess my curiosity about large differences in ETs got the better of me and I wondered if I had screwed something up.

I shall press on, content with with my own temps from now on, and change one variable at a time to check outcomes in the cup.

Cheers

Steven

My pic was manual roast, started at P5, then altered. You can see the P numbers along the bean temp line (added manually to the CSV file afterwards, as were my A and B temp readings) as I changed programs (trying to avoid getting the the temp cut out.

I will post up my probe set up later on.

Thanks Andy, will post my RM question in the post you linked.

Cheers

Originally Posted by artman

My pic was manual roast, started at P5, then altered. You can see the P numbers along the bean temp line (added manually to the CSV file afterwards, as were my A and B temp readings) as I changed programs (trying to avoid getting the the temp cut out.

I will post up my probe set up later on.

Thanks Andy, will post my RM question in the post you linked.

Cheers

I noticed the P values on the chart after my last post and realised then it was a manual job. You were working the Behmor buttons hard to keep in the right sweet spot - sailed pretty closet to the dreaded 166C !

Can I ask what program you are using to graph your csv files out of RM.

Thanks

Steven

Yes it makes it a bit exciting keeping the temp below the threshold!!

I opened the csv file in excel and inserted figures into the Colin's manually then opened up the csv as a template in RM.

If you do a dummy run and press all the buttons and slide the sliders you will see where the figures pop up in the csv and you can add your own values.

Cheers

Here are a couple of pics of my rough and ready temp people. I did this as a makeshift thing to try and do some diagnosis and it's been working a treat.

The probe is attached to the stainless piece (it's the bit in some windscreen wiper rubbers to make them stuff) with a bit of copper wire. The end bend allows insertion through a hole drilled in the left drum spigot and clears the mixing vanes.

The other bends make the end of the stainless "rod" sit on the base of the roaster so it doesn't spin around. The bead is situated at around the 7-8 o'clock position of the drum as viewed from the left end.

The "assembly " inserted into the drum- slid out from normal position.


In the drum in operating position.


Installed in the roaster.


Cheers

Nice work artman :thumbup: I'll give this a go when my heatsnob arrives in the mail this week.

Great work. Like the alternative to drilling even more holes in the Behmor. What thermocouple did you use? Where from? Thanks again.

Steven

Yeah for something that was meant to be a quick makeshift solution while I worked on mounting the probe through the the side (someone posted this version previously), it works very well. I just leave the probe in the lid so it's very easy. Not sure if with time the insulation will rub through (looking untouched at the moment) but I could always put a plastic (heat proof) bush in to protect it.

Not sure to be honest re what probe it is. Might be the one that came with the victor DMM (I think it came with this and the stainless probe?) or it could be from one of my other DMMs. Either way you should be able to get something similar from Jaycar, Altronics, the bay etc.

Cheers

Originally Posted by artman

Not sure to be honest re what probe it is. Might be the one that came with the victor DMM (I think it came with this and the stainless probe?) or it could be from one of my other DMMs. Either way you should be able to get something similar from Jaycar, Altronics, the bay etc.

...or from BeanBay!
CoffeeSnobs - BeanBay - Other Stuff - Spare Thermocouple Bead
(yes, it was originally shipped with the Victor and is in BeanBay as a spare part)

Sorry Andy. I did have a quick look and didn't see it on bean bay. That's the one I am using, great price too. Will have to grab a spare on next order.

Cheers

Thanks for sharing your windscreen wiper mod artman - working an absolute treat on mine too

I've done a dozen or so roasts and every single one has returned a nice smooth bean temp and most importantly, it has been consistent roast to roast.
Another bonus is that it has no problem with small batch sizes - the roast below is 190g in manual mode, and the probe remains completely in the bean mass.

Cheers,
Pete


IMG_1039.JPG16-05-19_1344.jpg

Is the stepped line the power level? Are you using a different control method? Looks like is it just under 90, as opposed to the built in 100, 75 modes of the Behmor? Or is the value on the graph just arbitrary?

One thing I have found with mine, is the the hole though the spindle is on a slight angle (drilled by previous owner), which causes the end of the probe to move around with each drum rotation. For small batches the probe comes in and out of the bean mass but only momentarily and it doesnt seem to affect the readout. So for people who are drilling their spindle, best done on a drill press so the hole is nice and square which will give you a steady probe.

Cheers

Just the default manual controls, the stepped line is the manual power level (100 -> 75 -> 50) - Artisan can be a bit hard to read like that.
The other line is the exhaust temp, but I'll probably ditch that soon.

Good advice on the drilling. I must admit, even WITH a drill press I still managed to put the hole slightly off center and on an angle
I tried sooooo hard to get it centered, but there you go.... It isn't too bad.

Also to note, Trico have wiper refills in two sizes (6mm and 8mm), The 6mm has slightly narrower stainless rails - so I went for those to give me more clearance...

https://youtu.be/PsCRU8YQ1nY

Cool slow mo vid!

I just happened to replace the wipers on the car the day before and hadn't turfed the old ones when I came across the idea. Good tip re different widths of stainless. Having a screw/bracket or similar on the sidewall might be easier to stop the rotation of the rod, rather than the vertical leg resting on the floor of the roaster. I find mine sometimes snags between roaster and door, no biggie though. Phase 2 future mod.

A centre punch should help with getting the drill started in the right spot.

Going back to the max temp question, I measured the volts across the wall sensor when it cuts out at 166 degrees and got 0.581 volts.

Cheers

Originally Posted by artman

...Going back to the max temp question, I measured the volts across the wall sensor when it cuts out at 166 degrees and got 0.581 volts.s

Close... the sensor will trigger Err2 when it reads 165C.... the 166C was "over-run". ;-)

FYI: when that sensor hits 180C you will most likely have bean ignition in the drum. We destruction tested one "to death" here a few years ago which was full of temperature probes and found that adding even 5C to the Err2 limit was flying too close to dangerous. Once bean ignition happens the temperature graph goes close to vertical and is uncontrollable at that point.

You don't need that much heat in the roaster to produce excellent roasts, if you are seeing Err2 you are probably ramping way too hot and are searing instead of roasting.

I did notice that with my wiring sorted on the main board the temp didn't really get close to the temp cut out on manual P5 so it looks like this should not be an issue if the roaster is functioning correctly.

Cheers

Hi Artman,

A quick question on your approach for inserting a bean temp probe into your Bhemor, what size hole did you drill through your axle? Also, where are you placing your ET sensor and is it also a bead type thermocouple?

Thanks,
Adrian

Originally Posted by artman

Here are a couple of pics of my rough and ready temp people. I did this as a makeshift thing to try and do some diagnosis and it's been working a treat.

The probe is attached to the stainless piece (it's the bit in some windscreen wiper rubbers to make them stuff) with a bit of copper wire. The end bend allows insertion through a hole drilled in the left drum spigot and clears the mixing vanes.

The other bends make the end of the stainless "rod" sit on the base of the roaster so it doesn't spin around. The bead is situated at around the 7-8 o'clock position of the drum as viewed from the left end.

The "assembly " inserted into the drum- slid out from normal position.


In the drum in operating position.


Installed in the roaster.


Cheers

Hi. Will have to check re hole size but you can not go too big as you need some metal left where it narrows for the spindle support. Also take into account eccentricity if you don't get it spot on. Mine was drilled by previous owner and isn't square, so the end of the probe moves up and down a bit as the drum rotates. Not really an issue.

I don't have an exhaust temp fitted, what additional info would this provide when roasting? I thought if you have bean temp you don't need ET?

Edit: hole diameter is 4.0mm, I chamfered the outside slightly with a larger bit. The stainless support strip is 2.5mm wide.

Cheers

Hi Artman. You are probably right about not needing the ET temperature. I just noticed a few people who posted their roast graphs had a line for ET and I thought it would be interesting to track, but as you said probably not needed.

Thanks for your help on this. I think I have an idea in my head of what it all entails and I look forward to doing it.

Adrian

No probs. I think the ET is done if you don't measure bean temp?

It's easy to do, you might need to re bend the wire to get it right so it doesn't clash with the vanes in the drum.

Also, I just leave the probe in the lid (yesterday was the first time I took it out to measure the hole diameter) and connected to the multi meter while I fill and empty beans.

Cheers

Just a quick update spurred by some discussion on the "whats in my roaster" thread.

The bead probe is still going well, the insulation on the wire has melted in spots (small internal fire - some beans escaped the drum), and is showing signs of wear where it kinks around the door etc but still works fine. I have bought a spare to replace this one but no need, it is still going well.

Another tip is to make sure you secure the wire to the wiper rod along the side wall, to make sure it doesnt snag on the spinning drum.

And I have not taken the probe out of the drum lid, I just leave it in there, doesnt really get in the way of filling/emptying the drum.

Cheers