Quest M3 Phidget probe question

Discuss roast levels and profiles for espresso, equipment for roasting coffee.

#1: Post by F1gpstar »

Hello, has anyone used the m8 nut on a quest m3 to fit the probe phidget offered. Thanks ... rodid=1240


#2: Post by jrham12 »

Bill, Those are the fittings I ordered for my M3 along with the 11cm RTD's when I was converting it from thermocouples to RTD's... Worked fine with the exception that the BT fitting interfered with the door a bit. My solution was to install it with a jam nut underneath it so i could lock it in place with a specific "flat" facing down towards the door. Then I marked that flat with a marker and took the fitting back out and filed it down to the point I could fully open the door. I ended up doing the same on the jam nut as best I could. I've had them installed for a couple months now with no issues.

I'm assuming that a clearance issue is the question you were headed for... :)


F1gpstar (original poster)

#3: Post by F1gpstar (original poster) »

Thanks Josh. I was concerned of it screwing in properly, and you confirmed that, and more. I'll just be ordering this for the bean temp only, along with everything else needed to hook it up. Any other tips for the Quest? It's brand new to me. It's a mrk II. Thanks again



#4: Post by edgndg »

Lots of threads here if you search, have you read Nunas' intro manual? It's a pretty helpful overview... ... 1.pdf?dl=0

F1gpstar (original poster)

#5: Post by F1gpstar (original poster) »

Hi Josh, I did. It was the first thing I printed off. It was a great start, and his replys to questions here are priceless. Thanks again


#6: Post by jrham12 »


I'll honestly tell you that I'm still learning as well since I just got my Quest about 4 months ago. It's a M3s that I picked up on FB marketplace. So I'm right next to you reading all the previous posts and learning how to better control my roaster and how to better anticipate when adjustments need to be made to account for the lag time in seeing the results in the ET / BT / ROR curves.
The majority of the roasts I've done have been between "drinkable" and "not bad" but I'm still working towards that first "wow" batch!


PS - this could get confusing since you have two Josh's responding to your posts!!! :)

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#7: Post by dcbrown1 »

Curious if anyone knows of a reason why just placing a probe (it's pretty snug) into one of the upper screw holes on the bean shoot isn't a good solution for MEV? I didn't use a coupler and it seems to be working great. Thanks!


#8: Post by jrham12 »


The two concerns I would have are:
1) If the probe moves at all (even rotates a bit), could it come in contact with the drum or the heating element?
2) By leaving that screw out, you now only have 3 screws holding the faceplate on (which also carries the weight of the front of the drum). Granted, I believe it has a "lip" or "boss" to keep it centered so probably won't be a big deal though.

I've read that most folks who use MET use a much thinner probe to get a faster temperature response, but that also allows them to drill out the existing screw to insert the probe without the worries I mentioned above. But if it is working well for you, I don't see a reason not to leave it that way... Although, do keep in mind that I'm still a pretty new owner when it comes to my M3!


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#9: Post by dcbrown1 »

Hi Josh. I just saw your note...thank you! (sorry for the tardiness!). Things seem to be working well. A few thoughts. The probe I'm using for the MET is indeed thicker than my BT probe (which I sourced from Quest direct). That said, the response time on the MET probe seems adequate. I suspect the changes in MEV are much slower than probe response time. I think what I need is a M4 screw or nut drilled out to 2mm...and a 1/16" probe. If anyone has a good source/part numbers, etc. that they'd be willing to share for these things, that'd be terrific! Thank! Dave


#10: Post by edgndg »

Hi Dave

If you search the forums, someone did a post re this. what you would want to buy is a vented M4 cap screw. I think I got mine from McMaster Carr. Then you need to buy a drill bit that can drill stainless (slowly) and find someone with a drill press. I did mine to fit the standard thin probe from coffee shrub.

Edit: this post - Quest M3s Thermocouple Mounting Hardware

Other Josh/Josh redux