Ambex Users

[peter]

My USRC 5-kilo is in the range of Stubbie's, maybe a bit higher. First is usually 345-370 and second starts around 410-420.  From my understanding, the main difference is thermal couple placement.

Peter, generally speaking on a timeline, what's your total roast time? Time fo 350-360? Time at first & second crack?  Time that your second crack ends? 

These are rough estimates, mind you... I simply have a basic profile that almost everything gets.

2.5min. to 300, sits there for 3min. to dry;
2.5min. to get to 350F, sits there for 3min. for sugar caramelization;
2.5min. to beginning of 1st, a couple minutes of slowly increasing temps.;
2min. or so after 1st for flavor development, by then it's a few vanguards of 2nd.

That puts me around 16min. for a C+ ~ FC, maybe 19 for a light Vienna.

[H-D Rider]

Thanks for the responses and I've already got some good ideas.
Chad, I was told the 150 equilibrium temp was what I should shoot for and the roast below I was trying for that.  It seemed low so my subsequent roasts were more in the 185-200 range.  Back to the 150 mark I guess.

I've found that 3# or more produces the best results.  A couple of questions

1) what is your drop temp for 3#
2) what are you roasting (high altitude grown beans roast differently)  Ethiopians are pretty high grown normally.
3) Time from bottom temp to 300
4) Time from 300 to 1st crack
5) time from 1st to 2nd

I'm fairly new to the Ambex too but have had some pretty good roasts out of it.. similar or better than the hottop.

If you are missing the fruit Peter is right.  You may be getting to 1st crack too soon.  Remember that stage is where the water evaporates out of the bean and if you get there too soon the water in the center of the bean doesn't get out.  I've been dropping at 300 with 3# and bottom out at 145 or so, then back to 300 in about 5 minutes and hover there for a bit then on to 1st crack in about 10 minutes hovering at 350 for a bit then off I go to second crack in 3 minutes after 1st has stopped. 

Charge temp was 280
Used Stubbies Brazilian
Bottomed out at 147 in 50 seconds
300 at 7 minutes from Charge
5 1/2 minutes from 300 to 1c at 384
2 minutes from end of 1c to first snaps of 2c and ended roast then at 408 degrees
Looked nice, even FC/FC+ by my guess.  Taste was flat.

On my Ethiopian I have only tried #1 roasts.  So the numbers are different, but still similar except faster from 300 to 1st.  I guess that needs to be lengthened out a bit and back to the 150 Charge temp.
Other Ideas or instructions?

[cfsheridan]

How long are you running full flame before 300F?  With the Brazil profiling we did, we'd set it up so the computer profiler would start controlling about 220F, with a bit faster time to 385F (~9-9:30 for a 2.5-3# roast).

[Alan]

You should give Terry Davis a call or drop him an email.  http://www.ambexroasters.com/index.html.  I'm sure they could give you professional advise to help you get the most out of your roaster. 

[Alan]

Wanted to add this forum as a reference source for information.  The unoffical Ambex roaster forum  http://billgiffen.com/ambex/index.php?sid=d0eafb6ca8aa23c896b0371615e0f93e
 

[H-D Rider]

How long are you running full flame before 300F?  With the Brazil profiling we did, we'd set it up so the computer profiler would start controlling about 220F, with a bit faster time to 385F (~9-9:30 for a 2.5-3# roast).

Chad
I have propane.  Full pressure is 10.  I ran full flame from drop to 240, about 4 minutes.  Then cut to 8 till 300 about 7 minute mark.  Full to just before 1c( about 10 seconds before ) then cut to 6.  still rising too fast(I thought) cut flame to 3 at 397 about the 14 minute mark. Ended at 15:30 @ 408.

Are you saying your profiles were about 9-9:30 to 385 from charge?  If so mine was about 4 minutes behind yours. Mine was 13:30 to first crack, which was at 384 on my machine with this bean.  I have found this one hits first with a small load anywhere fron 350-365 and with a 3-4# anywhere from 375-385.  Caught me by surprise at first because the hottop was pretty regular at 397-401.
H-D

[Ringo]

I am a want to be Amebex user but I found this.  It will be a help too me someday.     http://www.ambexroasters.com/pages/articles/article/managing_profiles.html   

[shep]

I ran a YM2 3-6 days a week for about a year and now run a YM10 about 3-5 days a week. I figure another 10 years or so and I might actually know what I am doing! As for bringing out the fruits, etc, I have to agree with Peter that you might want to stretch that pre-1st crack time out to better develop what you are looking for. That said, I am having the same problem with a Harrar that I have: very nice chocolate notes, but the fruit is quite muted and only pops as it cools. Had the same problem with it on my Hottop though. To counter that, I have a Guat Huehue from Coffee Holding that has some pretty powerful citrus/blueberry and it comes out very easily as long as I stop short or just at 2nd crack.

I did the Ambex training a few years ago and they did indeed promote a 150 degree equilibrium point. They also promoted a "leave the airflow alone" position, using full air. I back mine off slightly as my machine gets quite hot and it helps prevent chaff fires (although I found a new fix for that). Kathy Z from Coffee Holding Co was a big part of my training session and she was very helpful. She has experimented a lot with the Ambex machine and can be quite helpful. What I am about to say next is subject to personal opinion. I am not saying it is true or false, just what was promoted. In my seminar they suggested that the time to first crack was much more important than the time between first and second. They promoted a 13 minute to first time frame. Seems a little long doesn't it?

As for the comparisons of 1st and 2nd crack times, I have a few observations on my machine. First crack for me comes between 360 - 380, depending on the coffee and the time of year (yes, the time of year!). I have seen a big difference in the nature of my roasting in the spring/summer and fall/winter. Second crack on my machine usually comes between 424 - 432, depending on the coffee. Even though Ambex said it makes little difference, I have found the most challenge in stretching out 1st to 2nd times. One of the reasons is that I almost always roast full batches (15lbs for me) and it sometimes seems I do not have enough power to meet the criteria I want, forcing me to run full-tilt for the entire roast. This is typical for the first few roasts until I get the machine warmed up more. I counteract this by roasting smaller batches for the first few roasts. I am able to run a 4.5 - 5 pound batch on my machine no problem.

Shep

[cfsheridan]

shep,

Kathi Z taught my roasting profiling class, and she was working for/with Ambex when they developed their automated profiling system--she did the roasting and cupping, and worked with the programmers/engineers to get the profile system working.  A wealth of knowledge, and, in her new capacity, a good source of coffee.

[milowebailey]

Any YM-2 users out there have the version of the machine that has the electronic gas valve.  Instead of the manual/automatic switch it has a rotary knob.

If you do can you look and see what the make and model # of that valve is?  I want to replace my on/off valve with the electronic valve.

thanks

Milowebailey

[H-D Rider]

I'll check mine in the morning, that's what I've got.....................Milowidget in development, perhaps??

[milowebailey]

.Milowidget in development, perhaps??

.... maybe......

[H-D Rider]

Larry

The only number I could find on the Honeywell Valve was SV9501.   The valve is ahead of the control unit which is a Maxtrol M420RH.  Hope that helps. 

[cfsheridan]

Larry,

I'm getting another independent check from a roaster friend of mine as well.  It is a honewell, I know that.  Part # to follow.

[H-D Rider]

I just did a google search on the SV9501 and the pic is exactly the same as mine.  $130-190