Torrefattore

[MvO]

I have been roasting on a Quest M3 and enjoying it so much that I have been supplying family, friends and colleagues. No so easy with the limited batch size of the little Quest.. It was starting to take hours every Sunday.. I recently bought a Torrefattore that is almost new and am in the process of setting it up - electrician coming Saturday (hopefully) to install 20A circuit!

I have been doing a bit of google type research in hope of getting a few tips from others that have been roasting on the Torrefattore for some time. Unfortunately, not much luck...

There is an old Solar/Torrefattore thread on coffee snobs but most of that was written when the Torrefattore was quite new. Given that the Torrefattore has been out for quite some time now, I am hoping some owners can provide some tips. Any would be appreciated as I can only assume that roasting on the Torrefattore will be quite different to roasting on the Quest.

Also could anyone advise how far the thermocouple probe sits into the drum on their Torrefattores that have had the probe professionally installed. It appears that the probe was installed professionally however it only protrudes into the drum space by about 15mm, seems awfully short...

Although a little apprehensive about the new roaster, I can't wait to have a play!

Cheers

MvO

[JamesM]

Sell me your Quest.

[chokkidog]

Hi MvO

Don't get too hung up about the length of your probe ;-)
Except that too short a probe (and I'm talking 5mm) can receive too much interference from the roaster body or faceplate and give you an
odd reading with a flattish profile once you get around 160*-180*, which can be misleading, especially when 1st crack fires up at around 160*-70*!

So long as your bean mass probe is giving you a reading which is relative to the progress of the roast it's
not overly important what the actual temp reading is, so long as it's ball park.
Remember that the BM probe doesn't record actual bean temp but rather the air temp inside the bean mass,
as opposed to the ambient temp of the 'vacant' air inside the drum.

The thermocouple probe on my roaster (not a Coffee Tech) was fitted by the importer in such a way that the maximum depth
was only 5mm before it was hit by the mixing vanes of the drum as it rotated. I have had to experiment with a couple of different
spots to find a more optimal position.

I have played around with the depth of my thermocouple probe from 15mm - 30mm. There was no difference to the shape of the profile graph or
the outcome of the roasts. The only difference was the relative temperature reading for the progressive stages of the roast,
the range of difference was about 5*-7*. On the shorter length, 1st crack started 193*ish, 2nd crack 213*-15*ish.
The deeper setting : 1st crack starts 200* ish and 2nd crack scouts at 218*- 220* ish. I currently have it set at 30mm.

Ultimately, it's preferable to be as close as possible to actual bean temp but it's not absolutely necessary in order to get the best results.
What we are really trying to do is monitor the roast progress, so we know what's happening to temp increase *C/min,
the response of the roast to heat and airflow settings and the repeatability of our profiles, after that, it's about what's in the cup.

[MvO]

Sell me your Quest.

I will keep you in mind if/when I decide to sell it For the time being I'll be using it for smaller roasts.. Given the different roasting process, I'm not entirely sure that it would be wise to profile on the quest then try to translate that profile to the Torrefattore...

[MvO]

Hi MvO

Don't get too hung up about the length of your probe ;-)
Except that too short a probe (and I'm talking 5mm) can receive too much interference from the roaster body or faceplate and give you an
odd reading with a flattish profile once you get around 160*-180*, which can be misleading, especially when 1st crack fires up at around 160*-70*!

So long as your bean mass probe is giving you a reading which is relative to the progress of the roast it's
not overly important what the actual temp reading is, so long as it's ball park.
Remember that the BM probe doesn't record actual bean temp but rather the air temp inside the bean mass,
as opposed to the ambient temp of the 'vacant' air inside the drum.

The thermocouple probe on my roaster (not a Coffee Tech) was fitted by the importer in such a way that the maximum depth
was only 5mm before it was hit by the mixing vanes of the drum as it rotated. I have had to experiment with a couple of different
spots to find a more optimal position.

I have played around with the depth of my thermocouple probe from 15mm - 30mm. There was no difference to the shape of the profile graph or
the outcome of the roasts. The only difference was the relative temperature reading for the progressive stages of the roast,
the range of difference was about 5*-7*. On the shorter length, 1st crack started 193*ish, 2nd crack 213*-15*ish.
The deeper setting : 1st crack starts 200* ish and 2nd crack scouts at 218*- 220* ish. I currently have it set at 30mm.

Ultimately, it's preferable to be as close as possible to actual bean temp but it's not absolutely necessary in order to get the best results.
What we are really trying to do is monitor the roast progress, so we know what's happening to temp increase *C/min,
the response of the roast to heat and airflow settings and the repeatability of our profiles, after that, it's about what's in the cup.

Thanks Chokkidog!

The mixing vanes are most likely the reason the probe is so short on the Torrefattore. I was a bit surprised how short it was given that the factory fitted probes that came on the Quest are huge! I guess I just have to accept I now have a shorter probe and not get too hung up on the fact as you suggest. Like that say, it's not the size that counts, it's the way you use it!

Great to hear at you have undertaken some experiments with the size. I'll see how I go as it is currently set and might try my own experiments if necessary..

Cheers

MvO

[chokkidog]

Hi MvO,

I had a look at some utube vision of a Torrefatorre, the probe was in the discharge door, about halfway up and
under the left hinge. Is this where yours is?

In looking for a new spot for mine, I have drilled and tapped a new hole in my roaster door and have also
placed the probe in one of the sight glass mounting screw holes ( a suggestion from Andy).
Currently, it's in the latter position as I need to buy a compression fitting to hold the probe securely in the door, it wobbles a bit.
An option for you would be to try something similar; maybe in one of the door hinge screw holes? Or you could drill a new hole in the door
to suit a compression fitting, or have another way of keeping the probe stable; teflon tube or even paper wrapped around the probe to
keep it from metal to metal contact. You might be able to use the current fitting and blank off the old hole with a stainless steel bolt.
It might just be a matter of moving the probe position a few mm, bearing in mind the different batch sizes you are likely to run.

Mark at Coffee Roasters Australia (sponsor) might be able to advise on/supply compression fittings and threaded teflon fittings.
No harm in customising!

Cheers.

[MvO]

Hi Chokkidog

My probe is installed next to the sight glass about half way up and under the left hinge.. It appears to be done professionally and having read some old posts on the roaster, I wouldn't be surprised if the probe was installed by Coffee Roasters Australia when they first sold it. It appears that a hole was drilled out and a bolt without a head was then threaded in. This bolt has been drilled out in the centre where the probe sits. I'm happy enought with the location and the way it was done but just surprised at how short the probe sat into the drum as I was used to the huge probe of the Quest.

No I just hope someone has some tips on the Torrefattore for me?...

Oh, electrician didn't show but did send an SMS stating that he had been up most of the night fighting fires... Can't complain about that.. He is now coming Monday morning! I hope...

Cheers

MvO

[chrismelb]

Hi MvO

Congrats on the move to a Torrefatore, you will have some great results. Like you I am leaving a Quest and upgrading as well, hoping for the new arrival early Jan, yes the thermocouples on the Quest all seemed to be well thought out and and well placed, I moved the BT probe location for a trial but may move back to factory position.

I cant offer any info on Torrefatores but please, post on your findings. On my new roaster I too will have a very short probe and read what chokkidog said about probe length, will have to do some adjustments, thanks for that info - you have saved some head scratching.

[chokkidog]

Hi MvO,

That fitting which you described is a purpose made compression fitting, used for mounting probes.
Does it have a teflon sleeve?
All will be revealed once you start roasting, Mark knows his stuff, so I'm sure your temp readings and profiles will be fine!
It's a pity that the utube video doesn't show more of the actual roast and CS Roast Monitor progress but it looks like it's
pretty normal, if you pause the clip when the screen is in view.

Hope all goes well for you and chrismelb, looking forward to hearing of your progress!

Cheers.

[MvO]

Chrismelb

What are you looking at upgrading to?

I have been happy with the locations of the probes on the Quest and very happy with the roaster! Once you get used to the roaster it is easy to control the roast. If only it was bigger! What is the reason for upgrading for you?

Anyway hopefully I can get as good or better results on the Torrefattore!...

I'll update you with my results once I get an electrician out to install a separate circuit.. One guy came out but didn't appear to know what he was doing... Just kept scratching his head and making a hmmm sound...



Chokkidog

Ill look more closely at the fitting when I get home tonight.. Given that the probe cable is very bent and my data logger needs a k type fitting I decided to replace it for $15. The cable I have bought is rubber coated rather than braid. From what I have read it shouldn't matter?.. It is designed for temperature over 1000oC so no problem there...

Do you know how easy or difficult it is to remove and reinstalled the probe in compression fitting? It does seem very tight...

Cheers

MvO

[JamesM]

Chrismelb
I'll update my results once I get an electrician out to install a separate circuit.. One guy came out but didn't appear to know what he was doing... Just kept scratching his head and making a hmmm sound...

ABORT. hahaha

[MvO]

Chokkidog

I had a closer look but can't see a teflon sleeve.

Got another electrician coming out Thursday. Hopefully I'll have better luck this time...