Second Crack Profiles - please post - Page 3

December 11th, 2018, 1:27 pm

CarefreeBuzzBuzz wrote:Joe what are you roasting on? And these roasts went to SC? On my machine I need to hit 435 to 440 to get there?

I am roasting on a kaldi (low mass) with my ET probe in the chamber and some kind of Burundi bean, don't have it here. It did not hit 2c, but doesn't matter, my point is control is lagged like this,

So if I am trying ramp through a crash or ramping right before 1c to try to prevent a crash, then it's already way too late. So previous ET profile is much better/easier for me than doing something like this

If your roaster is high mass, then maybe try something like this

If doesn't get to 2c nicely, or wherever you want to go, then next time adjust your max ET and see how that goes. Anyway, getting hot and staying hot works better for me, so would recommend anyone having trouble at least try it a couple times. Maybe can get something out of it.

#22: Post by **FotonDrv** » December 11th, 2018, 8:51 pm

This is a second crack, roasted to light Vienna, decaf that mt wife likes. Roastmaster is the program and it is roasted in Centigrade.

I roast with natural gas and the numbers in red and the red graph line refer to this gauge.
The air settings 1-13, in light blue, are referring to the detent positions on the air damper. They translate to this in air flow read on the magnahelic gauge.

This is not the best roast but getting to vienna without causing a fire is always desirable. You will note that most of the temperature control is done with the air settings unless the heat was getting away from me and I needed to back off the gas.

December 12th, 2018, 8:37 am

@fotondrv,

Stephen,

do you subscribe to the charge high that is suggested. I think that needs to be one thing for me to try so that I have more room to extend into SC with a declining ROR?

#24: Post by **FotonDrv** » December 12th, 2018, 9:29 am

Michael, it more depends on the bean and how long i want the roast to last. My charge temps that i have been using are 190, 195 and 200C.

Getting different length roasts, like from a 10 minute roast all the way to 16 minute roasts is sort of dependent on bean moisture content imho. I tried a new bean that surpriningly to me went to FC in 6 minutes and other beans 9 minutes but most of the beans I have used will produce FC in 8-1/2 minutes.

I was watching a YouTube video produced by MC Roasters and he was killing the heat completely on charge and after one minute he lit the burners. It gives a lower turnaround and maybe less chance of cratering the beans, but that is justguess because I cannot remember why he was doing it. The MC roasters are pretty different than my MINI500. I have 5 burners and a cast iron drum and the heat can be changed very quickly. The roaster has very good air flow and I can set the heat in one position and just vary bean temp with the air setting. My drum speed is variable but I typically leave it at 80rpm with 350-400g charges.

December 12th, 2018, 9:39 am

Stephen,

Yes I do the one min soak. Maybe I should play with that as well for trying to go to SC. Having a single wall drum does make my heat changes a bit more responsive than the newer double wall ones they sell. So now I have two things to try to get to a declining ROR all the way to SC, charge temp and soak time. Thanks. Michael

December 12th, 2018, 11:36 am

CarefreeBuzzBuzz wrote:Yes I do the one min soak. Maybe I should play with that as well for trying to go to SC.

I've reduced the no-heat soak to 45 seconds on my roasts intended to hit SC.

#27: Post by **FotonDrv** » December 12th, 2018, 12:11 pm

I have played with the soak time too and it does have effect on when FC happens.

You can see from the roast profile I Posted that when I lowered the air setting the heat went up, I probably should have left the air alone and made for a more smooth tapering to the RoR.

#28: Post by **Almico** » December 12th, 2018, 2:18 pm

CarefreeBuzzBuzz wrote:... Some have told me that a flick at the end doesn't impact the taste and I can never get to SC without one...

Both of those claims are incorrect. A dip and flick will absolutely suck all the sweetness out of a dark roast and leave behind a hollow, baked & possibly roasty aftertaste.

And you can definitely get well into 2C without one.

On my air roaster I see a jump in RoR around 1:30 and another bigger one around 2:10. I do not like to add heat during a roast. I prefer to build the heat in the beans early and then coast the heat down as the roast progresses. This is not easy in an air roaster since heat is blown out the top and not retained. Around dry I will reduce heat if I feel I'm targeting 1C to quickly for this bean.

Some beans like to run away at 1C, some like to crash. For the runaways I'm also reducing heat at 1C a bit. For the few crashers I get I will increase heat a few seconds after 1Cs, sometimes drastically, to prevent it. I return it around 1:30 afterwards t prevent a flick. It makes a huge difference in the cup.

For runaways or crashers the MO is the same heading into 2C. Around 2:10ish the coffee starts exotherming. Heat needs to be brought down considerably to prevent the flick. For example: for a particular batch size I might be at 9kW at charge, I will be down to 5.5kW when 2C hits. The trick is to reduce heat gradually to prevent big dips in RoR. With a drum roaster you will likely be leading the reduction well in advance.

You can see where I reduced heat around 11:00 for this particular roast.

#29: Post by **FotonDrv** » December 12th, 2018, 5:13 pm

Almico wrote:I prefer to build the heat in the beans early and then coast the heat down as the roast progresses.

Some beans like to run away at 1C, some like to crash. For the runaways I'm also reducing heat at 1C a bit. For the few crashers I get I will increase heat a few seconds after 1Cs, sometimes drastically, to prevent it. I return it around 1:30 afterwards t prevent a flick. It makes a huge difference in the cup.

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I am finding this to be true as well, but hey, I am learning and having fun at the same time. Beats Charbucks any day

#30: Post by **Almico** » December 14th, 2018, 10:15 pm

Here's a dark roast I did tonight. It wanted to flick, but I nipped it.