The Quest M3 Coffee Roaster

The Quest M3 Coffee Roaster

ETA - August 1st 2014. It's hard to define exactly what the Quest M3 Coffee Roaster is, exactly; it falls in-between the current categories of small scale coffee roasters. It is hand-built, one at a time, in a small workshop factory in Taiwan. It has no advanced electronics, no motherboard or chipset, no heat profiling or automated cooling cycle. This is basically a miniature shop roaster scaled down to sample roaster size. It is a very manual machine and therefore most suitable for an experienced professional coffee roaster. It's not a Probat sample roaster (nor is it priced like one!) Yet it has some similar features: a sample trier so you can view coffee from the drum while roasting, a glass view window to see roast progress, manual temperature control (a dial adjusted gauge shows you the amperage sent to the heat elements), air speed control (fan speed controls volume of air pulled through the drum. A timer essentially functions as an on/off switch and allows you to cool the roaster down when you are finished with your batches, as well as acting as a safety shut off if the roaster is left unattended. It has an ingeniously simple way to cool the coffee; you dump the batch into the tray like a little shop roaster, open the rear door to the chaff collection chamber, and set the tray there so cool air can be pulled through it. Outside-the-drum cooling in 3 minutes or so ... another great advantage over most home roasters. Important! Turn the amperage all the way down when cooling your coffee. The drum will retain heat with the amperage down, but if left on it can overheat the roaster. The Quest is designed for continuous roasting, once it is properly warmed up you can roast for hours and in fact this is the way to use the machine, as heating it up to do one batch and cooling it back down right away could cause wear and tear on the drum. So, in this sense it is much more like professional sample roaster. The Quest M3 has lots of power and, as a miniature shop roaster it requires a knowledgeable operator too. You can have a chaff fire in a hurry without cleaning it, and it's not so consumer-oriented in safety design either; like a Probat, there are lots of hot surfaces to remind you where your fingers should and should not be during roasting. With an Allen wrench and a screwdriver the Quest M3 can be stripped of it's bodywork, the drum pulled out of the motor drive, and any part accessed in minutes. It is incredibly straight-forward in terms of wiring and parts. For example, it uses a commonly available computer fan for air intake. Heating elements can be changed out quickly, if need be. It is ready for any type of modification you might desire, such as PID control of the burners. (Not that I would want to automate anything here - the idea is a manual roaster with a trier to pull samples. Yes, it's a tiny, tiny trier but it works!) One improvement you might want to add over time is a thermocouple into the bean mass to read bean temperature while roasting. Roasters now come with a second hole drilled to accommodate this addition - it comes covered with a small bolt. The analog dial thermometer acts as an effective drum air temperature (environmental) reading. We did have trouble with the initial heating elements sent with the machines, but we worked with the manufacturer so now the heating elements have a higher electrical rating (up to 130v). We do have some in 220v available from this page. The Quest M3 is very quiet, and runs on standard US voltage (120v, 60 hertz). You'll be impressed with the ease, convenience, and consistency that you can achieve roasting coffee with this electric roaster. The ideal batch size is 120 grams which is a rather standard load for a modern electric Probat roaster. The absolute maximum batch size is 200 grams. Dimensions: 14.25" x 9.5" x 11.75" The Quest has 30 Day Warranty, parts are available for sale after warranty- contact: coffeeshrub@gmail.com We require previous roasting experience and signed Terms of Use. Processing of orders may take additional business days until this verification is complete. Full instructions for use can be found in the Quest M3 instruction manual.

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$1350.00

Side view
Side view
Top view
Top view
Rear view.
Rear view.
Cooling tray
Cooling tray
Heating elements
Heating elements
Accessories!
Accessories!
The cooling tray
The cooling tray
Circuit breaker reset button
Circuit breaker reset button

Power specifications label
Power specifications label
Heat and Air Speed controls, On-Off Timer
Heat and Air Speed controls, On-Off Timer
The cooling tray
The cooling tray
The trier
The trier


Thermometer
Thermometer

Heat and Air Speed controls, On-Off Timer
Heat and Air Speed controls, On-Off Timer

Comments

#1 Quest M3 K-Type Thermocouple

I wanted to post a bit about my experience so far with the k-type thermocouple that quest makes (and shrub now sells). I hooked mine up last weekend, and right out of the gate I was having real issues. The read out was very jumpy, and what really confused me was each jump was symmetrically matched between both of the ET/BT probes, but they were the inverse of each other.

The issue I eventually discovered (painfully) is that the casing for the probes (the entire length of the wire) is actually connected to the common of that probe. So, in my case, because the two probes wires (read: outer casings) were in contact with each other as they ran from the roaster to my computer, their voltage (and current) fluctuation due to temperature, were immediately drained into each other, hence causing my symmetrical disturbance. The wires have no shielding at all. If I kept the wires entirely separated, the graph was perfect and smooth. A long term solution is to cover the wires with electrical tape, or some other non-conductive coating (whatever works).

I wanted to share this, as this could affect anyone. Even if you're using one wire, if that wire happens to be touching something that is grounded (or otherwise), it could cause unexpected readings/results.

I hope this helps!

Andrew

#2 roasting time

I've developed a basic roasting profile that seems to work consistently and allows me to tailor the endpoints to my desired roast for the SO greens or blend. (NB: 110V version, line voltage is a stable 126.4VAC, usually around 230g load) I warm the drum to 160C using the BT probe. (Max amps, no fan, bean chute lid open) Drop the beans, cut the amperage to ~7A, no fan and chute still open. When BT rises to 150C, close chiute, crank amperage to max and run the fan wide open. At 190C, decrease to ~5-6A and lower the fan to somewhere between 1.5-3, depending on whether or not your fan is actually all the way off at the zero point. Monitor bean temp to desired endpoint. Elapsed time for the roast is 8-12 min usually depending on endpoint. I never roast beyond Roasted Coffee Pictorial Guide. ">FC+ and usually C+ to FC.

#3 triodelover, I would

triodelover, I would recommend never running full amps with no fan. It could reduce the life of the elements... a lot.

#4 +10! Hear, hear :-)

+10! Hear, hear :-)

#5 cpsuguy

Does any one else's first roast take like 20min to get to FC even though you warm machine up and drop beans at 210c?

#6 QUEST M3 ROAST TIMES

I am now at roast run number 81 (around 35 pounds of green beans total) . I have solidified on a batch size between 150 grams and 200 grams. I made myself a note on my log sheets to never use less than 8.25 amps except sometimes during the drying phase. I use a minimum to a 2.5 fan setting during drying. I will use between 9 and 10.5 amps during the roasting phase after drying (and fan setting of 4-6) and then reduce heat to there area between 8 and 9 amps before 1C, but never later than 1C itself. I will use increased fan to modify the length of time between 1C and drop which is at City to City+ for me. My times are usually somewhere around 8:30 minutes for 1C and drop at 10-12 minutes. I have done faster batches, but like these better. I have found that I have run into stalling at times when my amps got too low and lengthier roasts without a stall at other times, hence my rule of not using less than 8.25 amps during the roast phase and usually much more than that. I definitely agree that it takes time to actually get the unit to temperature. Without proper preheat you will notice a major difference between batch number one and batch number two on any day. I have done significantly larger batch sizes previously but dropped the size so that I can produce smaller batches to blend together to obtain the taste profile I like. In other words 2 - 150 gram batches with different profiles to blend into a 300 gram (minus moisture loss) final mix.

#7 It takes me in the range of

It takes me in the range of 8.5-9.5 minutes to reach first crack from when I drop the beans in the roaster for a 300gm load. I've recently been loading at 150c @ 10 amps, reducing to 8.5 amps after 4 minutes. Before I used to load at 170c @ 9 amps with fairly similar timings.

#8 First Batch Blues

The trick I've been using to beat the first batch blues is to toggle and fan between mid and low settings. I just watch the ET/BT temps to make sure they are rising eventually.. I find with the fan very low, the ET spirals up way faster than the BT.. if you run the fan for 60 seconds, the BT catches right back up and usually passes ET.. just let them rise together to somewhere above 400, and it should be good to go!!

Also, I'd agree with the other poster that running the fan at too high a level early in the roast would make it very slow in general.

#9 hmmmmm, it shouldn't. How

hmmmmm, it shouldn't. How much coffee are you putting in, and how long do you let the roaster sit at temperature before you load it? I like to let my roaster stay at temp for 20 mins or so before I drop the first batch. The therm might read the temp, but my experience is that you have to let it sit at the temp for bit to get it really ready. Even if, it shouldn't take 20 mins, I would imagine that has something to do with your energy and airflow settings.

#10 Loving my Quest

I've recently received my Quest and done probably 20 batches so far.. just want to echo the love for this machine. Buy it today!

I'm having no trouble with 8 oz roasts and can easily get FC starting at 8:00 minutes or faster if I want.. the cooling is amazing, and it really is easy to clean. Even between the drum and the casing via the hole near the back.

Happy roasting!

Andrew

#11 Great Machine

This is one great machine. Have now done 7 roasts. First 2 we learning experiences and last 5 were very drinkable. The last two were great. One question: I have read what I can find on removing the drum. I can get to the stage where the front plate is loose (removed 3 screws on plate face and 2 screws on circumference) and it seems the plate and drum should come out but gentle tugging does not seem to do anything. Do I just need to tug harder or is there another step?

#12 It takes a pretty sturdy

It takes a pretty sturdy pull. Just be sure to pull straight and be careful to not bend anything. It can also be squirrel-y to get back together so be careful. Lining up the drum casing with the groove is a little tricky. We don't really recommend taking the machine apart if you don't need to, for the record. It doesn't sound like you've done a whole lot of roasts to need maintenance, is there a reason you're taking it apart?

#13 QUEST MAINTENANCE

RE: Taking the Quest M3 apart. I guess it is the engineer and hopeless mechanical and electrical tinkerer in me that makes me take things apart and put them back together. I agree on there being no maintenance need this early. When I got it apart it was basically pristine everywhere. A small amount of chaff on the fan that needed a little coaxing to release, but that's all. Drum and roasting chamber spotless. I think doing lighter roasts helps with the cleanliness.

On a scale of 1 to 10 with ten being an engineer's (or technicians's) nightmare, working on this machine is a 1. For the mechanically adept, it is a dream. I am totally impressed with it's simplicity and elegant design. The more time I spend with it, the more impressed I am. This is definitely the machine I have been waiting for since I started roasting.

#14 stopped during roast

while roasting a sample I stepped into the next room for maybe 15 seconds, just walked in a grabbed a bottle of water from the fridge. When I came back the Quest sounded funny, too quiet. So I looked it over and the drum had stopped. My first thought was "Oh, I forgot to wind the timer" but no it was fine and the fans were still running. Weird, well I quickly turned it up on its end and dumped the beans, turned the heat off and used the brush handle to try and move the drum. It wasn't just a broken gear or something, it was stuck firm. So I left it to cool figuring I'd have to look on here and see how to tear it down.

After it had cooled completely, I started checking it out a little more. The drum didn't want to move, but I still seemed to have a bean inside and as I turned it over to dump out that bean, a small flat rock fell out too. And of course the drum started moving freely again.
So, I will check my samples over very carefully from now on!

#15 Stopped

Excellent observation Scott. It's really important to check all of your samples and to keep in mind that there is a gap between the drum and the front and back plates where something like this can get lodged. Thanks so much for sharing.

#16 need to calibrate thermometer

A customer said that the thermometer shipped with his machine was off by as much as 30 degrees - so if you are getting odd readings - it might be good to check the thermometer for accuracy by placing it in boiling water.

#17 Compared

So I cupped my samples from yesterday, 2 from the Quest and 2 from the Probat PRE 1Z. I used the Guatemala La Esmeralda Yellow Bourbon, which was crazy sweet and delicious with rich chocolate and date notes out of both roasters. I roasted on the Probat with my standard profile for samples:

- 100-115 gram charge (by volume)
- Energy set @ 8.5 (I leave it set here, the 8.5 is just a marking on a dial does not indicate amps)
- Charge @ 320˚F (environmental probe in the rear of the drum, this is the only time I look at the temp)
- First 1:30 the air is full open, @ 1:30 air set at 50/50, 3:00 air set at full closed
- First crack start at 8:15, 8:30 air set at 50/50, 9:00 air full open for 10 sec.
- drop @ 9:50

With the Quest batches I did a profile that I had worked out the other day
- 125 gram charge (by volume)
- Energy set at 7.5 amps, air at 4.5 speed
- Charge @ 220˚C
- First crack start @ 7:30
- Air full speed for 20 sec @ 8:00
- drop 9:40

Very few adjustments with the Quest, but I felt that I was getting the development that I wanted this way. I also was basing my drop time on time from the end of first crack along with the odor from the beans (really impressed by that little trier on the Quest).

The cups were very similar flavor and sweetness wise. The main differences were that the Probat batches had slightly more body, maybe a bit more depth of sweetness because of this, and the Quest batches were brighter with a bit more defined acidity adding a bit of an apple tart-ness to the date notes. I attribute these differences to (as I theorized above) the different methodologies of air control in each roaster. I will continue to play around and take actual before and after weight measurements next time, this should be at least a little telling.

Overall though, I am really pleased with the results of this exercise. The clarity in the cup of the Quest roasts is spot on for sample roasting, and I still have plenty of room to play around with to try to get the body in line with the Probat roasts.

#18 Great Suggestion Above

I read this and do pretty much this exact same thing and it's great. NOTE that ceschooley states gram charge BY VOLUME. That's the 125g line on the little clear cup provided. I did 125 grams weighed out on a scale and I kept roasting too fast. After re-reading I cought the "by volume part". This comes out on average to be about 142 grams weight.

Great suggestions, great sample roaster.

#19 questions about the above method

thanks for the tip on the 142g that makes great sense! I blindly tried 125 and it was crazy.
so in terms of the air being turned on full, is it a 'full' setting relative to what the beans can handle, or is the dial turned to 9? Theoretically a full airflow setting would speed up a roast and a 9 setting on my quest seems to introduce so much air that it slows/stalls/reduces the temp in the drum.

#20 reply

stephenmentze,

I'm still working on tailoring this roast profile because I'm finding that the roast may vary +/- a minute or two depending on the coffee, but I can tell you what I've found about the air flow. I think you're right that it stalls out this little roaster to turn the fan full on so what I'm working on is to turn the Amps up earlier in the roast to prep for that temp loss such that it can push through and head to an appropriate final drop temp.

As for "speeding up the roast" I think what we see when we increase the fan speed and then see an increase in the temp readout (depending on the location of the temp probe/thermocouple) is just hot air moving through the roaster more rapidly across that thermocouple. I feel that the bean temp is still steadily increasing an may not be as high as the temp probe/thermocouple is displaying and that eventually the actual bean temp and the temp we see come to equilibrium.

For example, On my 18 kilo roaster I have a temp probe higher in the roaster near the entrance for the green and also a thermocouple a little lower in the drum for bean temp. When I turn up my fan during first crack to get some excess smoke and humidity out of the roaster, that top temp probe rapidly increases while the thermocouple stays at its steady growth rate. As I come toward the final temp, the top temp probe hasn't changed much but the lower thermocouple starts to read closer and closer to it. Do you see the same things as you roast?

I'm trying to take some learnings from things like that and drastically scale it down and see if they apply. I'll update any roast profile that I come across that seems any better than ceschooley's but I may not since he's a genius. No matter what profile I come up with though i have a feeling that I'll have similar time variation problems since coffees are so different and we're roasting on such a small scale. I'm just attempting to make it a little more controllable and to roast a little longer (not full production roast though).

Lastly, keep in mind that the trier is right next to that probe, so if you're getting lower temp readings and you're looking at the trier a lot near the end of the roast, it may affect what you're seeing.

#21 quest profiling

Thanks for the reply adam. I think it is interesting that you are turning up the amps to push through, my response was the opposite. I started using a 6 on the airflow instead of going all the way up to 9. Actually, I have torn this profile apart. I was roasting some natural ethiopians and started dropping at 195C, then wile roasting a Kenyan (second sample), I dropped from 210C to get a little bit more time at the bottom so as to accentuate some sweetness. Then I broke down further and would start with a 6 on the air to lengthen out the early stage without dropping at a lower temp.. what is interesting is that it does seem to slow down the development. I mark by smells, grass, hay, bread ect.. and like you said the temp will rise quicker, but those markers seem to still happen at a steady pace. and using a 6 on the air seems to actually slow that pace down. Or at least for a little wile. I can't really decide what I think. it's almost as if using lots of airflow over a larger period of time just creates momentum that once started can't really be stopped. what I mean is that my environmental temp can get super high and if I take the air back down going into first crack I can still rush through it, like the beans slingshot into equilibrium with the energy in the drum. I might be a little crazy.
My experience is limited to just the quest at the moment. I spent a little time on a small diedrich a few years back but don't remember the specifics of this kind of stuff. So I can't comment much on what I've seen on bigger roasters. I think I have done just about every variation imaginable on the quest though. It is amazing how many different approaches one can come up with for a coffee and still achieve something drinkable in the end. It would be cool to hear how ceschooley came upon this profile and hear what else has been tried. I found some stuff he posted on the roasters guild about liking high heat and low charge settings and have also found a lot of people enjoying higher airflow for the last portions of the roast as opposed to the beginning.
I would love to hear what other people are doing on this as well!

#22 Quest For Better Coffees in Nebraskaland.

We're loving the Quest as a sample roaster. On the other hand, it's our only option at this point, and we're not picky. We tried the Hot Top and passed quickly on it. In the past, I bought a used Palini & Alves double barrel roaster, turned around and sold it rather quickly due to the fact that it was poorly made and smelled terrible. I must say, for the price, the Quest does a much better job than the previous industrial-style Palini, and it's more manual and simple to use than the Hot Top. No filters or programs, all of which seem silly to me. It's like trying to add a "1950's convenience" mentality to a craft that seems to me to not benefit the coffee. I saw the most recent Behmor 1600 home roaster review online. It looked like a microwave, and the guy (who seemed like a very nice fellow) kept on saying something like, "you can't add more time after a while, because it's programmed to a certain profile" also, there's a smoke suppression device. I'm convinced the Behmor 1600 is a quality roaster with great results and programming, but it's not the style in which I feel comfortable in approaching coffee.

I'm a lover of all things manual, especially when it comes to coffee. It kind of reminds me of selling espresso machines. Do I choose to sell and promote super automatic espresso machines to customers who are in search of the best quality tasting experience or the fastest, easiest, push button good enough coffee for businesses who feel the need to maximize their profits?

Back to the Quest: It's quiet, consistent, small, and also a great choice for home roasters. But I do have critical notes too;

http://cultivanotes.aimoo.com/SAMPLE-ROASTING/Quest-Notes-1-386986.html

We have a forum where we take notes, share info on spot samples and other roasters in the industry who send us coffee, share profiles, etc. If you take a look under our categories, and you'll see further info. Please feel free to sign in, say hi, and add any suggestions on sample roast profiles, times, amps, fan speed, and what has worked for you, and we'll give it a try!

here are some recent posts on our forum:

POST #1

"Day 1: out of the box"

the cupping room on 11th street just-so-happened to have an exhaust system that was not in use, and in perfect working condition. the set up was easy. We decided to locate the duct directly behind the QuestM3 in order to remove as much smoke from the room as possible. It may have worked too well, since we noticed a slight stalling when we located the duct directly behind the roaster. we ended up moving the roaster about three inches away, allowing the roaster to run on it’s own predetermined airflow speed without the vent disrupting it.

ups and downs: day 1

the ups

it’s electric.

It’s easy to find a power source and doesn’t use a crazy amount of power

it’s small

The footprint is very minimal, it's light yet seems pretty durable. I like the metal. it's sleek. no paint! I hate paint on a sample roaster. I’ve seen many single barrel sample roasters, and this one seems to do the job well enough for the price. Compared to other home roasting units, this actually reminds me of the same level of quality the ECM espresso machines when compared to commercial units, if that makes sense, or dare I say GS3? maybe with some improvements...

it’s manual

After experiencing the hottop and other home roasters, the ablitiy for this unit to not have silly filters to replace is wonderful. Also, there is no automated programming functions. The dials are very manual, although I would prefer dials which have “steps”, not just four or five, but as many as possible. “digital steps” would be nice, so as to show the exact amount of electricity being used for heat, and the airflow adjustment having steps would also help control variables. With “stepless” adjustments, much like grinders, it’s very hard to precicly replicate profiles, but again, you loose an amount of control or opportunities eliminating infitine adjustment. we don't have them on our Diedrich anyway, so it's nothing abnormal, I would just enjoy to see more accuracy in adjustments. In any case, digital timer, temperature, and airflow would be wonderful, and I’d likely invest more to have it as such.. A Celsius/Fahrenheit temperature gauge for the US models would likely help, although I'd love to go fully metric myself:)

consistent

it seems to have the ability to replicate profiles easily.. this is only the first day, four roasts, and we hit exact time temps on the last two batches. It’s looking good.

The Downs

it’s electric

I don’t know if it will effect the cup quality, so this will be determined by several rounds of blind cupping within the next few weeks. Also, it’s only an assumption, but electric might be harder to increase and decrease temperatures during the roast, but we’ll see if it’s even a concern.

it’s slippery

without rubber on the metal legs, or something to hold it down, it’s easy to move, worst case scenario, slide right off a table. I’d suggest to hold it down somehow. I’ll likely clasp it to the table tomorrow.

vague adjustments

The adjustments, as it came, are not as accurate as I’d like. They seem to be good enough, but more accuracy would improve the ability to replicate the profiles. There’s a green mark on the airflow nob, but no mark to match it up to to determine what the “lowest” airflow adjustment is. We were told that the lowest airflow is adjusted by watching the speed of the fan until you don’t see the fins anymore. This is pretty loose, but it seemed to work. Some speed dial airflow gauge would be a huge improvement. Along with adding a digital control for the electrical heat monitor. I also wish there was a light to help see the bean color.

No funnel for the hopper

It’s pretty easy when loading green coffee for a few beans to get trapped into the air passageway above the drum. I think it would be neat to replicate the traditional style of roasters by adding a stainless steael funnel ontop, and it would look nice too!

Exhaust is messy

I would love to see the exhaust have some sort of standard ductwork adaption added, so people could easily hook it up to a ventilation system. It would also be nice to have the exhaust come out in an upward or adjustable direction, rather than a flat panel out the back. It’s okay, but I think there’s room for innovation here.

Overall impression after day 1

I can’t wait to roast on it again.

I’ll be curious to see how many batches per hour I’ll be able to roast, how often it will need to be cleaned, and how consistent the profiles can be. the time it takes to cool down in between roasts will be observed and noted. "

POST #2

SPEED TRIAL:

I gave the Quest a 15minute preheat, began roasting at 945am and was done right before 11:00am.

I was able to roast 7 batches, back to back without stopping, within an hour of roasting time.

the typical roast profile:

charge temp at around 185-200C
charge air position: FULL
Charge amp level: 8A

I changed the airflow typically around 1:30min to allow the beans in the cooling tray to have some time at full air speed to cool rapidly. at 130min I decreased airflow to 4.5, the slow fan speed.

gas remained at 8A until the beginning of 1st crack, which typically hit around 6min, then I lowered the Amp temp to 7A, and then gave full airflow until the end of the batch. At the very end of the batch, with about 10-20sec left, I killed the amps completely.

after dumping the beans and placed into cooling position, I immediately charged the next batch, temp usually being around 185-200c, and put the amps back up to 8 at the beginning, and repeated this process 7 more times with a few variations, partially due to distractions of taking notes, not paying attention, etc. but generally they were all very manageable. the roaster didn't go up in flames, etc. pretty easy hour, with 8 samples.

Fears:
they may have all been too fast, but after talking with others in the industry, I thought I'd give 6min 1st crack a try, with an average of 2 minutes from beginning of 1st crack to the end of the roast. never at any point did any of these hit or see any signs of 2nd crack either.

I'll cup these tomorrow and post notes on what the results show!"

CONCLUSION:

I noticed there had been a concern with the heating element burning up, but so far, with much continual use, we've had no problems with the roaster and have had very consistent results. Not only is it a great roaster, but the name can be used easily in clichés, puns, and fun dialogue!

Always on the Quest for better coffees,

Jon Ferguson
Cultiva

#23 Questin'

So impressed by this little wizard. Very consistent from batch to batch, although you will have to lower your charge temp after a few batches due to how hot the whole device gets. I am at this very moment running some comparison batches between this roaster and the Probat PRE 1Z electric sample roaster. Both being electric roasters, I tend not to make too many adjustments to the energy setting, although I do really like that the energy setting on the Quest is directly related to the amps and I plan to do more experiments with energy settings. But today I want to look at airflow.

Operationally, the Quest can behave very much like a sample roaster, but one difference between this and the PRE 1Z (or other open faced sample roaster model) is how they respectively use airflow. With the PRE 1Z, you adjust the airflow to slow the roast by opening up the airflow to draw cooler air through the face and also draw some of the radiant energy from the drum. To speed the roast up, you close off the airflow in order to trap more of the radiant energy and reduce the draw of cooler air through the front of the drum.

With the Quest being a closed face drum (with the drum exhaust positioned at the front of the drum) , increasing the airflow increases the amount of energy introduced to the charge because it's drawing the energy over it. The other way that the airflow is different is that the PRE 1Z uses a damper set up to limit or increase airflow, while the Quest uses a variable speed fan. I'm not completely sure (and I'd love to hear other peoples' thoughts on this), but I think that using a damper system helps curb moisture loss in a way that variable speed airflow adjustment does not. This can easily be measured with post roast weigh out and moisture loss calculation (today I just wanted to run some roasts as I normally would and put them on the cupping table to look at the differences, I did my batches volumetrically and didn't think of weigh outs until after the fact, so... next time) . The solution to this is in how and when you adjust the fan speed. I will continue to experiment and post my findings here.

All of this being said, so far I have found the Quest to be extremely easy to use with extremely repeatable results while honestly making very few adjustments at all. Which makes it an ideal sample roaster. I also would like to look at some of its other uses though, being rather versatile it can reproduce production style roasts in a way that most sample roasters cannot. Of course if you are doing darker roasts, smoke can become an issue. The volume and versatility of this roaster can allow you to do roasting experiments and exercises that you wouldn't otherwise really get a chance to do in terms of training and skill building either because you couldn't achieve the results with your sample roaster, or you couldn't waste the volume that you would need to use in your production roaster (who can?). I will post some exercises that you can do here in the comments section in the near future.

Anyways, the Quest is on. Looking forward to hearing from y'alls about your experiences.

#24 air flow

Here is my simple experiment, to answer the question of air flow in the Quest.
I kept the power at 7.5 on each roast, same 125g for each charge, vacuumed the chaff out between each roast and let the beans cool and removed them so each roast would be identical, with the only variable being airflow. Had already roasted 4 previous roasts, so the Quest was hot.

Kenya AB Nyeri
Charge Temp 200C
Power 7.5
Full air flow throughout the roast
1st crack at 15 min, (very light not even sure I was hearing cracks)
Finished at 19 min @ 192C
Not sure this would have ever reached 200C and to compound it, every time I used the trier the temp dropped 5C.

Kenya AB Nyeri
Charge Temp 200C
Power 7.5
Air Flow mid range- with the little sharpie mark at 4.5 sitting at the 12 o'clock position.
1st crack @ 10:30. Few solid pops up front then barely audible.
Finished at 17 min 200C. Struggled to get it to 200C

Kenya AB Nyeri
Charge Temp 200C
Power 7.5
Air flow with the sharpie line at 9 o'clock, not the lowest setting, but I was hesitant to put it at its lowest.
1st crack 5:15- solid first crack
2nd crack started @ 8:25
Finished at @8:25 and 215C

Sent from my iPhone

#25 question on air flow experiment

Hi Scott,

Thanks for posting the results of your experiment. Can I ask you two questions? is the 125 grams by weight or volume and which mounting hole are you using for the ET thermometer? (under the trier or on the other side)

Thanks,
Dan

#26 Hi Dan,I went with 125g by

Hi Dan,
I went with 125g by volume, using the little measure cup that came with the quest. That seemed to be the standard most people are using.

Not sure about the Thermometer. It's just a factory setup, and I set it up according to the directions that came with it. I'll check tonight and let you know. I know Tom has a Utube video on installing a thermocouple, which I'd really like to do, just never have a drill motor handy when I'm thinking about it! I think Tom just drilled right through the door, if I remember correctly.

The thermometer is installed below the trier.

#27 back to back roasting on the quest

Thanks Scott,

I have now had a few weeks of working on back to back roasting and am finally getting the hang of things. I have been working with a 150gr (by weight) batch size and am pretty consistently hitting first crack at about 7:30 and dropping at around 10:15- 10:30. I'm keeping the amps at 7.5 and just manipulating the air flow as needed..I still need to work on a few things but so far so good...

thanks for helping out!.... Dan

#28 Hey Chris, still like to see

Hey Chris,
still like to see some of the exercises you offered to post, if you have time! Thanks!

#29 Hey Scott, thanks for the

Hey Scott, thanks for the poke. I would check out the experiments I did for the Stretching the Roast articles:

http://coffeeshrub.com/shrub/content/stretching-out

They're not Quest specific but very easily executed on the Quest for sure. I'll definitely do some trials and post some profiles that I used for those.

#30 Yes I did enjoy your articles

Yes I did enjoy your articles in that series! Even referred back to them today as I played with the Kenya AB Nyeri, I'm still having some difficulty deciding if increased airflow actually increases the temperature in this Quest. Sometimes it seems to make no difference at all and other times it seems turning the air flow all the way down will increase temperature rise. The cryptic instruction sheet for the Quest states an increase in air flow will cause a 'too low temp in the roller'. But conventional closed drum roasting wisdom is the opposite. I would like to do a few experiments to answer this, but I haven't really given it much thought beyond that I want to figure this out!

#31 Questin'

Great info,

I would be interested in your impressions at a slightly larger batch size, in the 200 to 250 gram range as well as results of profile roasts to maximize bean's potential.

#32 Air Flow: Damper vs. Variable speed

I do imagine that at this volume the differences might not show significant variation, but I think that it will be fun to look at it.