Note how the pipe angles up toward the front of the roaster because of that male fitting not allowing it to sit on the bottom of the roaster? Not sure if this is a good idea or not but I know it is not resting on the burner elements.

The white crappy looking stuff in the photos is the painted white, chipped, military ammo cans that the roaster is sitting on and it is an ugly reflection.

Foton,

Thank you very much for sharing the photos of your mods. Your Quest looks great.

I might be missing something, but why not take that male part of the tubing of so it doesn't angle, or is it not that big of a deal?

Also I just completed my next experiment and I will be posting it soon. I am running into the issue of how changing 1 variable effects other parts of the roast and It might not be plausible in so strict of a sense. However we shall see. I will be cupping in the morning.

Cheers.

amh0001 wrote:Foton,

Thank you very much for sharing the photos of your mods. Your Quest looks great.

I might be missing something, but why not take that male part of the tubing of so it doesn't angle, or is it not that big of a deal?

I had the pipe from a plumbing job and was to lazy to cut the adapter off. Once I realized it fit without loosening anything AND it sat in the front of the roaster away from the burners I thought it might be a good idea and worth a try. It might work better laying on the bottom of the roaster as well, I just have not tried it.

Just a small update,

I added to the original thread

"***PS I am using an older Quest with the trier on the left. and most importantly I am using Eric's thin probe in the BT2 location that goes through the screw the sight window (most people use a bigger probe in BT1) . This is will always make our graphs different if we are using different probes in different locations."

Also I was asked for UltramaticOranges guide. It can be found here. all props to him.
https://drive.google.com/file/d/0B9ohp2 ... VNQ1E/view

I will post some updates soon.

Okay, So for the next experiment I tried changing charge temp. Now that gets a little confusing as I am staying with keeping the amps the same.

Here are the graphs




I tried to keep only the charge temp as different, and drop as soon as first crack stopped.

During cupping I had a pretty hard time telling the difference between these, except that I wasn't wild about either of them. They were not very clear or juicy fruity. They were both thin bodied, and a touch roast.

To Amh0001:

Its hard to compare your two roasts because of the large difference in MET. I think that that has more of an effect than the BT charge temp... The difference between the roasts up to End of Dry is 2 minutes - and that cant be because of the 40 degree difference in charge temp. Regarding to my experiences at least...

****I changed the title of the thread as I do not believe it is ideal to only change one thing in a roast.

OH, I added a 5inch copper pipe like suggested in this thread. I found it at lowes for 5 bucks, it slipped right in, and I added a rubber Oring on the outside to keep it from falling all the way in. So far I have done about 15 roasts with it, and I notice that it keeps the temps in the roaster from falling as much when increasing fan speed. It is also about 60f degrees in my garage when I roast. And my drum is not insulated. I dont know how much of a difference this makes in the coffee, which just goes to show that the roaster makes the biggest difference not always the mods =).

I was reading on Sweet Marias about roasting 2 different profiles. Cupping them, and attempting a new one based on what you like/disliked.

I also in this post was inspired by TomC and some of his comments. I am using TC on some graphs only to note that it was inspired by him, and may not be anything of what hes doing.

I ordered some Columbia lotes from sweet marias that received some recent hype. I tried roasting them 2 different ways.

I noticed in some of TomC's graphs that he draws out the drying phase a bit then kicks it up a notch to finish, more of an S then a C shape curve (on graphs).

So here was my attempt to mimic that, I obviously do not have it mastered. I also used a larger charge size at 175. I have tested this a couple times and dont really find a difference from using 150g as my normal charge size so I went back to it.


here is a more Roa style roast


Tasting notes:
the first roast came out pretty nice. It has no flavors of bake or underdevelopment. It has the most sweetness, but it is hindered a bit by a present roasty character. I would say this would make a fine dark roast.

roast 2 also does not suffer from major flaws. It has no bake or underdevelopment (ie paper wood vegital). However it is slightly underwhelming. It lacks the sweetness that first roast has. It has a bit less body and clarity, but is not a BAD cup, its just okay.



My next two roasts I used a washed guatamala from bohdi leaf that has "juicy" as a flavor descriptor so I call it juicy guat =).

here is the first roast


and the more rao style


So the first roast in this batch had major flaws of paper/woody flavor that gets in the way. I trashed this batch. Underneath this off flavor are some guatamala notes with a small touch of acid in there, but pretty uninspiring.

The second roast has notes of paper, but hidden more in the back. The cup is very simular to roast 2 of the columbia where it was a bit underwhelming. I wouldn't describe either of these roasts a juicy.


So what im trying to take away from this is:

I need to keep some things consistent so I can compare my results better. I will keep my charge weight at 150g, and my charge temp at 350 ( i need to look at my MET too) unless experimenting with it.

I think there room for improvement by stretching out my drying phase a bit. Something in cup one is sweet. Take away the burnt roast flavor, and add some clarity of the SO flavors and THATS what im after.

Anyways, I know my attempts at roasting are all over the place and im trying to hone myself it. Feel free to give me any suggestions or grounding points to work on.

Cheers,
Adam

I notice that most of your roasts take a long time to get to the yellow/dry stage (150-degrees C or 300 F). You might be picking up some leathery notes from this. You might try keeping the heat up higher and longer at the onset, before backing off. This would give you time to stretch out the ramp (dry to 1C), thus reducing the toasty notes. It would also help to bring the drying and finishing time into better balance (I like to see them roughly equal), which is sometimes a challenge when doing roasts as light as you are. Your quick finish times (two minutes and less) would likely be giving you a bit more acid than I like.

FWIW, it took me a really long time to get the balance right on my Quest. No sink shots, but some uninspiring roasts at the onset. It was made worse because I was used to the much brighter notes from fluid bed roasting. Conduction roasters like the Quest are quite the opposite...nearly no air effect. Bash on!

Thanks for taking the time to reply Nunas!

A couple questions tho. I dont actually hit DRY END in these graphs till i see the coffee going tan. As you can see I am hitting 300 around the 4 minute mark. Do you still consider that a slow rise? also, I thought (correct me if I am wrong) you want a shorter middle phase for brighter coffee.

I did some more roasts with some Ethiopian Yirg I got from Green Coffee Buying Club. Here is some graphs:

The first one, I tried to follow the ROA guidlines of declining ROR, 20% dev time, and energy at the beginning.


For a contrasting style, and for trying to lengthen the dry phase I tried this, I realized it was Slow Start, Fast Finish SSFF.

I cupped these roast the following day, and I found the BOTH of them were extremely lacking in body, and not overly fruity for a Yirg. No discredit to GCBC, the coffee does look very well processed and of high quality, just not an extremely fruity crop.

The first roast seemed short in flavor and a bit muted. The thin body really didnt help.

The second roast was my preferred cup, as the coffee tasted more rounded and a bit clearer with a longer taste.

Seeing as I have 5lbs of this coffee, I wanted to see if I could increase the body. I read through sweet marias "stretching out the roast" and saw:

"We've learned through this set of experiments that you can alter the perceived acidity by stretching out the time after the end of 1st Crack (Part 1), alter the perceived body and mouthfeel by stretching out the 1st Crack itself (Part 2), and alter the perceived acidity as well as sweetness by stretching out the drying stage of the roast (Part 3). "

So in this roast my goal was to Stretch out first crack. And since I liked the SSFF coffee better from above it was also a bit more like that.


Now I was quite pleased with this roast. Not because it was extremely fruity and a great coffee. But that It actually had MUCH better body and was a really well rounded, fully developed coffee. I felt like the roast was good, anything else lacking was from the coffee.

Now I have to admit, when I first started reading the internet about roasting, there was a bit of debates about the SSFF and the rao styles. I remember thinking to myself that I was much more confident in the RAO approach, and that I wanted to work on that. But after tasting some of these results, its like TomC said, "trust your pallet".

Another thing TomC told me was that my increase in BT during development was too little and possible baking the coffee. In this thread the better coffees that have tasted well roasted have both had big increases in BT through development. I am starting to think that is a key factor.

I am not for sure, and will definitely keep experimenting.

After taking into consideration of the comment about MET being different, and reading Raos book some more, I decided to do 4 roasts of a the same coffee and try to hold a steady MET temp with a steady fan setting. I went with 540 560 and 590. The first roast took over 12 mins and seemed to stall out at times. The last roast was super fast like around 6 minutes.

I was cringing watching my ROR graphs on the roasts. I cupped them all and guess what.....

They were all pretty good. No noticeable baked flavors or paper flavors in any of them. However the coffee I used was very acidic and it was a little too much even in the 12 min roast. So i decided to go with a around 10 min roast and let it develop a little bit more. It was a bit too roasty the it was developed better and a little sweet and less overly acidic.

This has made me realize how i need to monitor my MET and how I can use it to actually guide my profiles....


Another note on handling first crack. According to Rao's advice on sample roasting he recommends dropping the heat about 30 seconds prior to first crack. I found that because the Quest lacks thermal mass, I had better results getting through first crack, trickling heat off about 30-45 seconds after the beginning of first crack.

I am now working on trying to get my coffee sweeter and better developed while, keeping the MET lower to avoid any roasty notes...