Quest M3 Mods - Page 3

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

#21: Post by kwantfm »

FotonDrv wrote:Nice funnel, you must have access to a sheet metal shop that can weld stainless!

Does that straight tube part extend past the cross heat return pipe/carry handle on Quest?

I made my funnel out of scrap in the shop and it is heavy but the beans slide down to the bottom of the load chute easily and sure makes loading Quest a snap. If I had a sheet metal shop around here I would use them for sure!!
Yes, the shop I bought the reducer from was able to do the welding. The straight part does extend past the heat return pipe so it all works very well.

How's all of your Quest modding for other HB'ers going?? I'm certainly looking forward to that HG one mod once you have time.

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#22: Post by FotonDrv »


I have been busy doing some mods for the Quest and slowly as time permits working on the rotating arm cooling bin. It will be just a bin and when the beans are cool it will have to be lifted off and dumped as opposed to a dump door.

Can anyone see any difference on moving the MET thermocouple probe from the top right of the loading chute to the top left?

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TomC (original poster)
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#23: Post by TomC (original poster) »

Here's some more modification ideas for the Quest M3; simply adding high temp thermal insulation to the outside of the roaster. It certainly helps stabilize the ET a bit better and requires less babysitting of the MET during the roast to a certain degree. I didn't really have to change my roasting technique, it just made it a bit easier to profile all together.

A fairly easy and reversible modification that only costs about $30. It took me about an hour, but that was partly because I was taking pictures and tiptoeing thru the task. Parts from McMaster-Carr are:

9379K93- Ultra-High Temp Foil Faced Insulation Strip

7594A8-Extreme Temp Aluminum Foil Tape * ( in retrospect, wider tape would be helpful as well)

Tools required: Utility shears, N95 dust mask, disposable nitrile gloves, flexible measuring tape.

I spent a good deal of time trying to figure out which materials to choose as far as utilizing the material without having to trim and modify it too much. Knowing that it would essentially be fiberglass, I didn't want to have to carve it up much and have particles everywhere. The foil faced insulation strip is exactly 3" wide, and the drum, is just a hair over 6" long, so I knew I could get the job done by simply lying 2 sheets parallel to each other and securing it with the foil tape. You can see from the photo below that the insulation isn't very well attached to the foil. It's a bit fiddly getting it to behave the way you want.

It's relatively self explanatory, but a few tips are to carefully fold over the ends of the insulation to help trap the fiberglass and give you a clean edge to tape down.

It's not glued to the aluminum and easily slips off. I'll likely go back and run one strip around the horizontal exhaust tube as well, but I used up most of my aluminum tape, so I'll save that for likely later on in the day after I go to the hardware store for some other unrelated things I need, I'll pick up another roll of aluminum tape. This roll was only 1" wide, and it's not the most adhesive stuff in the world, so in retrospect, I'd go with a wider tape.

The drum diameter is 54cm, I cut each strip at 57cm and still had a slight gap ( unimportant for the most part), the gap is out of the way, underneath the bottom. I took the wire cage off, set it aside, and also unscrewed one side of the lateral drum mounts at a time, meanwhile I supported the drum with my Cafelat tamping stand and a microfiber towel, which just happened to be the perfect height to support it all without any undue flexing.

Sliding in one at at time and taping it in place along the drum face, midline, and rear. I worked around till I had both pieces wrapped and gently tapped, paying close attention to the midline seam. and taping everything down well.

Then replacing the wire cage and gently squeezing and tightening the aluminum tape down where small gaps appeared. The wire cage holds everything in place nicely and still secures well, but I might pick up a few wider washers, since on one side, I had to screw them in a bit lower, where the gaps between the individual wires are wider. It probably won't make a difference, so I'll just watch it for a while and add them if I feel like I need to.

One thing that reinforced the fact that I need to use a wider tape than the 1" was the fact that the lower areas were quick to come unsecured and hang a bit. But the 1" tape was nice for the detail work of securing it down around the drum face and rear, to prevent the insulation from being exposed to my roasting environment. After the wire cage is back on, it's easy to go back and push and tuck around to close everything off nicely.

I ran three roasts (it's super early in the morning and I was awake, but I didn't feel like making it a super long roasting session), but it was quite apparent that this helps stabilize the ET a bit and it allowed me to get thru a profile without as many tweaks to the heat. Sequential roasts were nice in that, I was able to see a dead straight ET/ MET prior to charging my next roast. It also gave me a good extra minute or so between roasts without losing heat. I usually re-weigh my cooled beans and update the Artisan profile so I can save it, before moving on to the next roast, and this modification allowed me to do all these little tasks without worrying about my ET caving down or soaring up. And this was with the fan running at 4.
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#24: Post by FotonDrv »


Thanks for the write up!

I wondered about the functionality of the roaster if the insulation was added.

Do you need the squirrel cage now, or is it still to hot to touch?

Best Wishes,
That Light at the End of the Tunnel is actually a train

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TomC (original poster)
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#25: Post by TomC (original poster) »

I think the "squirrel cage" helps because it will prevent wear and tear of the insulation, where I might otherwise handle the drum's shell, I can place my hand on the cage. It will take several more roasts to be sure, but I'm pretty certain that I need slightly less amperage thru the various parts of the roast. And I can still hear all the cracks of the roast just fine.
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#26: Post by FotonDrv »

Thank you!
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#27: Post by sversimo »

I did the same thing with my roaster. The biggest downside for me was that it affected the temperature response. I could not lower the temperature fast enough, making the machine very hard to control.

I ended up with a heat exchanger instead.

Do you see any difference in the temperature response time?

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TomC (original poster)
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#28: Post by TomC (original poster) replying to sversimo »

On successive roasts, the stored heat will take longer to bring down if that's what I wanted, but for the most part, it's right where I wanted it to be anyway. I've only done 4 roasts since I did it, but it seems rather consistent. I can't really roast anymore for a while, my freezer is filling up with most of my roasts because I haven't been drinking as much coffee as I normally do lately.
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#29: Post by Beanz »

Tom I am considering insulating my Quest and would be interested in your feedback now that you have a few months roasting experience with the insulation installed.
Has it had produced a noticeable change in the roasters performance in terms of roast size or the time taken to respond to changes in heat or fan settings during the roast ?
Have you expererienced any downsides similar to those mentioned by sversimo ?


#30: Post by robmatic »

TomC wrote:Here's some more modification ideas for the Quest M3;
7594A8-Extreme Temp Aluminum Foil Tape * ( in retrospect, wider tape would be helpful as well)
Quick followup on this mod, since I just did it to my Quest a few days ago...

Instead of this tape, I ordered 7631A72, which is "high temperature aluminum foil tape". The difference between this and the "extreme temp" is that this tape "withstands 325F" as opposed to 600F for the extreme. I was slightly concerned about this, but I ran a test on my roaster, running the heat up very high. The drum temp got up to 660F(!) but a naked thermocouple placed just under the "high temp" tape measured only about 300F. So I think that the high temp tape is adequate, and it also has these advantages over the extreme temp tape:
  • it is 2" wide (instead of 1")
  • it sticks a lot better
  • it is much much cheaper (around $3 vs $17)
So far, I am finding the insulation to do its job very well. Much more heat is retained, and I need to use less power in general. More specifically, I am learning that now I need to back off the power sooner than I had been doing in the past.