1.25 kg Halogen Roaster

[ajay]

A while ago I posted about the setup I was using for roasting using a breadmaker and halogen floodlights.
http://coffeesnobs.com.au/YaBB.pl?num=1196336104/new
That rig is still operational but because it is restricted to 5-600gram, I decided to upsize to a larger capacity roaster.

The new configuration uses a bigger, double-paddle breadmaker called a Breville Breadmaster Bigloaf. It is paired with an off-the-shelf 1500w floodlight as the heat source, loaded with a second 1000w light. I vary the heat of the smaller light with a Jaycar dimmer.

The breadmaker has been modified to bypass the regular circuitry so that the motor starts when it is switched on. The control panel has been replaced by a piece of cement sheeting.
The original paddles were not giving me enough agitation for large bean volumes, so I experimented in enlarging them by folding some sheet brass around them. As this worked nicely, paddle development has gone no further.

The light is mounted above the breadmaker with some bolts which enabled me to adjust the height of the heat source so as to maximise heating without overheating the beans on top. It is hinged using the floodlights glass frame (without the glass) and the wallbracket is now a heatproof handle, so I can easily keep an eye on progress.

I started off roasting a kilo of green beans, reaching first crack around 11 minutes with  all 2500w. I then ease off with the dimmer. I found that I was able to increase the capacity to 1.25 kilos, which adds a few minutes to the time it takes to get to first crack, but roasts routinely finish around 18 or 19 minutes. I find this a convenient roast size as it is half a Coffee Snobs green bean bag. The drop weight is just over a kilo.

I will post some pictures of the machine in action shortly.

cheers
Andrew

[ajay]

Re: 1.25 kg Halogen Roaster

Here are some pictures of the progress of 1.25 kg of Ugandan Masaba - First crack was at 14 mins, second crack was at 18mins and I pulled it at 18.30.

The photos show:
1. Green weight
2. In the roaster
3. 5 minute mark
4. 10 minute mark
5. 15 minute mark - tail end of first crack

[ajay]

Re: 1.25 kg Halogen Roaster

continued
The photos show:
1. 17 minute mark - nearly at second crack
2. In the cooler (box fan blowing through a big middle-eastern sieve)
3. Detail of beans
4. Bagged up

[Koffee_Kosmo]

Re: 1.25 kg Halogen Roaster

I love coffee snobs ingenuity
Well done
KK

[A_M]

Re: 1.25 kg Halogen Roaster

I love coffee snobs ingenuity
Well done
KK

I concur [smiley=tekst-toppie.gif]

In addition more fun and cheaper than the imported machines ya have to pay for

It looks like ya limited but the bread maker and its ability to hold much more at full expansion.

I guess teh next mod; is a simple SS skirt to clip on and off lift the volume when ya need that special 1.5 or 1.75kg roast

[flynnaus]

Re: 1.25 kg Halogen Roaster

Thats brilliant ajay. The bread maker looks pretty full by the end of the roast but no signs of tipping.

I think thats a winner - simple design, large capacity, heat controllable. It is purely radiant heat trather than fan-forced so looks as they it might be gentler than using a heatgun.

How will the halogen floodlight stand up to the greater heat generated?

[WSullivan]

Re: 1.25 kg Halogen Roaster

Looks like a VERY even roast 8-)

Hows the taste? I can see roasted swap potential!

are you using the CS datalogger software and USB DMM to monitor your profiles? Are you able to post up a profile?

Well done!, i had a look at your original post, it amazes me that this didnt take off(as in people copying you), one of the big advantages is the fact that if you blow a bulb.....its a couple of dollars and your on the road again!!

Awesome!

[Andy]

Re: 1.25 kg Halogen Roaster

Excellent looking roast AJ.

Im surprised that the paddle stirs that large volume of beans so well, I would have expected a very patchy roast.

Dumb question... where does the chaff go without the air flow of a heatgun?

[Dimal]

Re: 1.25 kg Halogen Roaster

Great roast "ajay".... [smiley=thumbsup.gif]

Out of interest, where did you buy those Bag Clips? Looks like a great idea..... 8-)

Im surprised that the paddle stirs that large volume of beans so well

Looks like a modified Breville "Big Loaf" BM Andy. These things have dual paddles and manage to move the beans around really well. Also, it looks as though "ajay" has increased the size of the paddles on his machine unless of course, Breville did this on later models of the BM....

Mal.

[Mono]

Re: 1.25 kg Halogen Roaster

The original paddles were not giving me enough agitation for large bean volumes, so I experimented in enlarging them by folding some sheet brass around them. As this worked nicely, paddle development has gone no further.

AJ actually mentions in post #1 that he has modified his paddles with some folded brass sheet to increase agitation.

Steve.

I also like the bag clips.............perfect for the purpose

[WSullivan]

Re: 1.25 kg Halogen Roaster

I also like the bag clips.............perfect for the purpose  

This is the one thing in the photos that i didnt like the look of :-[, i would be worried about early spoiling if the clips are all that is stopping the oxygen from getting in :-? i personally use my bags about 5 times, heat sealing them slightly lower each time, then when its time to crack, i just carefully cut off the sealed bit and it leaves me plenty of room for another seal or 4 before tossing the bag, my 200ml heat sealer cost $30 delivered. ITS AWESOME!

PS Everything else i love!!!! Great little invention there!!! 1.25Kgs 8-)

[Dimal]

Re: 1.25 kg Halogen Roaster

i personally use my bags about 5 times, heat sealing them slightly lower each time, then when its time to crack, i just carefully cut off the sealed bit and it leaves me plenty of room for another seal or 4 before tossing the bag, my 200ml heat sealer cost $30 delivered. ITS AWESOME!

Yep,

I do the same Warren (except I get 8-10 uses from each bag )...

Thought it might be a useful thing to know for those people who dont own an Impulse Sealer. I imagine it would be quite effective to be honest - Seal via the Zip-Lock and then fold over and apply the Bag Sealer.... Should work OK..... :-?

Mal.

[WSullivan]

Re: 1.25 kg Halogen Roaster

They make a massive difference mal, i couldnt believe the difference in taste, only problem being, some beans, in particular the Indo Mandheling i currently have, de-gasses like there is no tomorrow, so you have to make sure your one way valve works effectively, ive noticed on some of my Di Bella bags that i re-use that the valves are very tight and occasionally the bag gets to a near popping stage before some of the gas is allowed to escape, this can result in a slight CO2ey tasting shot for the first couple after the bag is opened......

But yeah, best $30 ive ever spent......with the exception of my first kilo of espresso WOW (the single reason im a Coffeesnob ;D, it got me hooked in the very beginning)

[A_M]

Re: 1.25 kg Halogen Roaster

But yeah, best $30 ive ever spent.

And never to be repeated... I think $42 is teh min now..

[ajay]

Re: 1.25 kg Halogen Roaster

Folks,

Thanks for your interest and praise (keep it coming!). What I have done with this machine is expand on an idea that I already knew was workable. It has taken a bit of mucking around and fine tuning to get it to a stage that I am happy with.

Hows the taste?

I am very happy with the results in the cup. I stuck with the halogen radiant heat because I found it improved the taste and consistency of my roasts.

are you using the CS datalogger software and USB DMM to monitor your profiles? Are you able to post up a profile?

My dmm is RS232 only. I used to record my roasts on the shed pc, but as things became predictable, I felt like it was a pointless exercise. Oh and something funny happened with my readings, too. It used to be that I always hit first crack at 204, then it dropped to 184. Maybe the thermoprobe needs replacement. Anyway, the short answer is no. Currently my temperature readings serve a purpose in that they tell me when I am about to hit first crack and assure me that I have a slow, steady increase after that, but they wouldnt give you meaningful comparative data. If that changes I will certainly post a profile. THe new software looks like it shows rate of change, which is attractive.

cheers
AJ