another_jim wrote:(Slightly OT) In the Hottop, does the fan draw air over the heating element, and then into the drum?

Came across this photo in my archives showing the vent under the chaff tray

Randy G. wrote:* I use a permanent stainless steel mesh rear main filter (intended for computer fans) instead of the stock, consumable filter. This changes the airflow compared to the stock filter. Adjust the heating element and fan speed to get the desired results.

I have the e-bay site for the stainless or aluminum filters. "Will this filter operate with out any harm to the Hot Top roaster?" If it will, I don't see any reason why anyone would continue to use the original throw away filter that comes with the unit.

More than likely the issue is harm to the user due to particulates. The original filter traps much finer particles than the fan screen. If using indoors, use a vent to remove the exhaust.

This is my roasting profile for the HotTop:

http://www.sweetmariascoffee.com/forum/ ... 0&start=20

I've been roasting with a Hottop P for about 3 years, 250 roasts.

Best profile I have would be equivalent to 100% until 1st crack and a quick reduction as rolling 1st crack hits to an output that holds the 1st crack chamber temp. Part of 1st is exothermic and I guess the probe is still catching up as well to the true temperature in the chamber so the 1st crack temp climbs about 5-10F from the start of rolling to a rest even after gearing down heat input. My usual temperatures are about 380F-385F for start of 1st, 390F-400F for rolling and a level off of anywhere between 405F-412F. If the temperature gets too high after 1st the rest to 2nd is shortened. 2nd can hit pretty fast if you don't throttle down just at the start of 1st. The goal for me, and it reflects a roasting profile I agree with, is to set the beans up quickly for a 1st crack and try to level off for good rest to 2nd. I try for 3 to 4 minutes. Lately I've been ending the roast either short of 2nd or at the first hint of 2nd. I find I like the taste of a lighter roast better. I used to roast until just before rolling 2nd which brought out some oils and a darker roasted character.

I've roasted to incineration as well and it's true, the Hottop dumps the beans at around 431F. Lots of smoke. The trick, I think, for dark roasts isn't hitting that high temperature but a fast ramp to 1st so you've got a longer time to dwell in 2nd crack. 2nd crack starts for me at about 412F-423F and with the extra time add ons I've been able to get some really oily, incinerated roasts.

Thanks to all who have taken time to provide info, advice, suggestions, profiles etc. Have tried many of them and now have a much better feel for distinguishing between differences in roasts; still have some learning to do as all of the results have generally been good but difficult for me to determine which is "better".
John Davis

Regarding that condensing moisture in the HT or any other roaster.

Here are some facts :

- Beans are usually quite dry but some are "wet" ;
- The higher the temperature of the air, the more it can absorb water ;
- ET is always higher than BT except at the end (depends on profile) ;
- I assume after the 1st crack, there isn't enough humidity left in the beans to produce condensation.

Since ET is always higher than BT, condensation can't occur in the roast chamber -- except at the end sometimes BT will be higher than ET ... but there's not enough humidity left in the beans to produce condensation.

Correct me if I'm wrong but the only way I can think of condensation happening (dew point) is external cold air entering the roast chamber, like those roasting specially those roasting outside in very cold weather -- OR perhaps the chaft tray OR electronic room being very very cold due to external temperature and a dew point might happen.

If condensation happens in the chamber, it means the surface temperature of the beans and the drum is being cold down a lot. I doubt this is a good idea... I would try not to use the fan at all but like I wrote before, it can be the chaft tray producing condensation AND/OR it might even happen within the back of the HT (motor, electronic compartment).

Comments are more than welcome!

PB

Droplets in the roast chamber itself at the end of the roasts will be coffee oils; since water would flash boil.

I don't actually know what exactly is in the vapor coming out of the roaster, I'm sure there's water during the first crack, since with high acid beans, it sometimes smells like getting misted with vinegar or lemon juice. And the cracks themselves are from the release of steam. Not sure if any free moisture is left once the first is done.