drgary wrote:So you say it isn't repeatable ... how do you control it to get good espresso? I've got a thermocouple and meter, is there a way to use that? And I wonder, just to get my bearings, do people ever use their convection ovens for roasting coffee?

I said

It doesn't lend itself to accurate temperature measurement, though, so it isn't good for repeatability

What I mean is that while you can get a good espresso roast each time, you probably won't roast *exactly* the same batch to batch.

I can put a batch of beans in my Pid'ed iRoast, and roast them to a profile, then do it again, and put the beans side by side and be unable to tell the difference. With a HG, especially without experience and without the experience of being able to read the surface of the beans, you won't have that level of control. That doesn't mean that you won't have good espresso - it just won't be 100% consistent. But that's okay, at least for starters. As you get more practiced you will get better results, and eventually you may build a better roaster.

I tried getting temps off of my HG roasts, but had a very hard time getting any consistent readings, but that is probably partially due to my setup, using a fry basket nestled into a rice cooker bowl; it is hard to tell if you're getting the heat-gun output, versus the beans' temp, and you don't want to stop roasting to take a measurement.

These days I rarely do the HG roast, but I love the rawness of it. I get more consistency from my PIDed iRoast (the original iRoast was crap for consistency, which is why I started doing HG roasts) but if I'm roasting up a few lbs for an event, I'll drag out the HG, since my iRoast can only do 150-160g batches.

As for using a convection oven, folks have married together the Stir Crazy popcorn popper with a Turbo Oven convection oven. The result is a "SC-TO".
http://homeroast.pbworks.com/w/page/18982530/SCTO

Allon,

Thanks for the great advice and links. I get your point that not being exactly repeatable doesn't mean no good. Now I've got some reading to do!

I just upgraded my old hottop D to the B controls, much better now. One other thing, when beans hit first crack the go exothermic and pump out a lot of heat which can run a roast out of control and into 2nd with next to no pause. At the first pop of 1st I crank the fan up to 100% and cut the heater to 10 or 20%. The watch the the bean mass thermocouple to make sure I do not stall the roast. Then as I see the temp rise slow and 1st starts to slow a touch I crank the heater back to 90% and cut the fan to 10% to coast the roast to my desired finish point. You cannot do that on your current rig but if you end up with a hottop it may be useful.

Thanks, Dave. The Hottop is still my likely next substantial upgrade and practical tips like those will help me climb the learning curve faster. What do you think of trying some of these other methods to start getting a feel for roasting? I was very surprised, for instance, that having a feel for an AeroPress made it easier to learn a manual lever! Or is this more like my early attempts to try and use a Saeco Magic cappuccino Plus to pull espresso? Too wide a deadband and too little temperature stability to be useful?

Tasting 3 - 5 days post-roast

I found that these small batches are very hard to assess for espresso as there's so little available to dial in and differentiate coffee characteristics versus brewing parameters being off. I pulled shots on my Duchessa because it yields greater flavor clarity than my Amica and uses a 51 mm double basket compared to the Amica's 58 mm, allowing for more shot samples.

drgary wrote:Because the time from 1C to 2C was longest and the roast didn't stall, I'm guessing that 35 gm is the ideal.... 35 gm ... 1C was 2:49 first pop to 4:00 and 2C began at 6:53 and was ended there.

Well, tasting tells me it's way too bright for espresso, and this is an espresso blend. It is much better as an AeroPress, where there's flavor clarity and a complex resiny spiciness. Again, dialing in is an issue. I would now use 1 1/2 scoops instead of 1, and I might brew it a little cooler. Didn't measure with a thermocouple (too lazy and also just getting my bearings). My temperature control technique with a microwave is to fill a Pyrex with 1 cup of water and heat two minutes more or less. I find that varying by 10 seconds and when dialing in by 5 seconds makes discernible differences.

drgary wrote:I tried upping the dose keeping the power cords the same now. 45 gm, 1C 2:08-4:05, 2C 5:00 and ended, but now the beans were smoking. This told me temperature might have gotten too high at the end.

This batch lost the unpleasant brightness but was quite ashy. Not sure without more trials, though, whether the temperature of my pulls was off.

drgary wrote:40 gm, 1C 2:25-4:01, 2C 6:30 and stopped there. Now the beans weren't smoking.

This was the most successful batch and a starting point for later tries.

Interesting thread Gary, Im more or less a beginner roaster myself but Im really liking the HGDB method. I played around with a Poppery for a bit and also struggled with trying to stretch out the roast time to improve the espresso.

I kept reading threads like this one where guys with much more experience than I were harping on the benefits of the heat gun method and getting a "feel" for the whole process.

I may upgrade in the future with something to get more consistency and control but honestly, Im just doing this for myself ( I drink most of the coffee at my place) and just enjoying the experience, each time I order coffee I try something different.

I heatgun roast about 10 oz at a time and try to keep a few notes just in case I hit on something that really knocks me over. Its all been drinkable and most of it has certainly been better than I can get at the store.

OK guys (including jammin), I'm sold on HG/BM approach and will try it when I get a chance!

OK. While on BART (Bay Area Rapid Transit), after doing the last post, I went on Craigslist and found an Oster Bread Machine for $25. It's on the way.

Tonight, thanks to jammin's offline suggestion, I ordered a Porter Cable 1500W heat gun model PC1500HG for about $40 from Lowe's. This allows low and high temperature settings and low and high fan settings. No need for an add-on device to regulate voltage.

Further research on this site shows the bread maker may best be used for bread and that a metal sieve, a metal cooking pot and a thermocouple may give me accurate temperature readings for adjusting the roast profile. See: Thermometry for Heat Gun / Dog Bowl Roasting I would simply stir with a dowel. I'll have to read some more to see if I can get good thermocouple readings in the bread maker.

OTOH, some apparently achieve very good results with a dog bowl, a stirring stick, no thermometer or bread maker. See this post and the thread around it: Heatgun/Bread Machine (HG/BM) specific roasting discussion

I think the answer is to roll up my sleeves and have some fun!

fist off - I'm way excited for ya to get started!

I ordered a Porter Cable 1500W heat gun model PC1500HG for about $50 from Lowe's

That is the same gun I have. I used a permanent marker to make tick marks on the heat dial(not pictured). This helps me know exactly where to turn the dial for the desired roast speed. The low fan/power setting is great for creeping up on desired roast degree - a half pound roast will slow to nearly(but not quite) a stall when you shift into low. Mine has held up to several roasts in 110* + weather and survived roasting in multiple sandstorms.

I'll have to read some more to see if I can get good thermocouple readings in the bread maker.

I get VERY consistent temp. readings with my cheap k-type t/c I bought from Amazon. I believe I bought 2 for $6 shipped. I use the t/c reader from Sweet Marias that I picked up for about$35(?).

Maybe a picture would be more helpful:



close up of T/C placement:



I have since "gutted" my bread machine. All the electronics have been removed and the motor is direct wired for constant stir. This is nice because I don't have to wait 5 minutes for it to quit "pulse" stirring and go to constant. I also don't have to worry about the thermostat telling the machine it's "too hot" after a roast. I would often have to wait for it to cool down before it would start again - plus the 5 minutes of pulsing. This may have partially been due to the extreme temps. here in Baghdad though. I followed this most helpful guide posted on Homeroasters, it took about 20 minutes total:

http://www.homeroasters.org/php/forum/v...ead_id=528

Cheers,
~j

Good deal Gary, I use the same Porter Cable heat gun. I havent "advanced" to the breadmaker part yet (that means I havent found a cheap one)

If youre using the bowl method the variability of the Porter Cable isnt necessary, you can just vary the distance from the beans. I beleive that would be infinite variability

The setup like Jammins is the way to go when you get tired of stirring, very nice