roasting green coffee beans What You Cooked Last Night Discuss roasting green coffee beans in the Brick Oven Cooking forums; I will source the stainless wire this week and have a long weekend coming up to make it all. I ...

[Rastys]

I will source the stainless wire this week and have a long weekend coming up to make it all.
I have plenty of wiper motors as I work sat mornings in a wrecking yard and get them for free as they never sell.
Hooked up through a variable rheostat, you have infinite speed control, so set it to what you feel is suitable.
Thanks for your input, muchly appreciated and will get back with the progress made as we have a large pizza cookup and now fresh roasted coffee for the espresso machine on 28 June.
Cheers.

Rastys

[Rastys]

fornax hominus
Well, we're making progress. I tried to get some stainless wire mesh but was pretty expensive, had too come from interstate, would take a week or so to arrive and they wanted too much for a simple delivery, so I sourced some small aperture expanded steel sheet.
I bought an off cut with enough to build another 2 roasters for $36. Came home this afternoon, cut the sheet and folded it, I thought that a hexagonal one would be easier to make (as I don't have a set of rollers to form it properly), but would aggitate the beans better whilst roasting.
It took around 2 hours to make and I plan on a rotisery base with provision for a tray to slide in under the roaster for when I use the set-up as a rotiserie.
I can't see the point in making some thing for a single purpose and by putting a stainless shaft into the base will become a rotiserie for that side of lamb or smallish pig.
The opening method is simple, with just a single wire pin pulled out from the 4 protruding lugs and hey presto, it's fully open.
It measures 400mm long and 200mm diameter and should hold several kilos of beans but I only plan on roasting a kilo at a time.
I have left a protruding lip in the roaster to aggitate the beans and can add others if needs be.
All it needs is a bake and a lick with some steel wool to clean it up a little.

Rastys

[Rastys]

All done!
Now it needs cleaning a little, some good green beans and a hot oven.
I decided to make the stand to stand inside the oven and be used as a rotiserie as:

http://www.fornobravo.com/forum/f35/...erie-4352.html (Neill's Pompeii rotisserie)

I made it adjustable height, to fit easily through the oven opening and can be used for a roaster or change the shaft to a stainless for a rotiserie capable of an 850mm long cook. There is also access for a tray to slide in to empty the beans or a drip tray for the rotiserie.
I will need to cut one small semicircular holes in the oven doors so that the heat can be contained within the oven when the shaft is protruding through. I also need to insulate the drive motor from heat for the longer bakes.
I did not fit a motor yet as I will hand crank it for the roaster initially whilst I think the motor/drive system through. This is not a very long time as I have been studying up on coffee bean selection and roasting.
Neill has a couple of ideas but I need to take into consideration the adjustable height, viewing access into the oven past the drive set-up and also safety factors.

Rastys

[fornax hominus]

Rastys
Oops, my post yesterday must have fallen under the bus ... I noted that your octagonal design will expose more beans to the heat than a cylinder which would require baffles to stop them sliding to the bottom as it rotates.
I can see where you want your door shut for the rotisserie operation , but for coffee the thing about roasting with open door and the fire still going is that you visually have to check how things are going towards the end .
As well different factors come in to play , type & quantity of of beans, temp. of the oven , and with me [not you] the outside air temperature [I have roasted beans @ -20c .. not fun!!].
Great work on the roaster!

[Rastys]

The hexagonal design has only one baffle/paddle at present, at the hinge, but I can very easily add more or even angled smaller ones to mix the beans up more. The ones sliding around the ends of the roaster could be chanelled onto the centre and visa versa. I just want to keep the open edges free from baffles for ease of emptying the beans.
I have just joined a coffee forum for more advice and to get a few answers to my brewing/espresso making.
I will get that exceptional brew yet.

Rastys

[fornax hominus]

Rastys
I have been an espresso coffee maker for 16 years , 10 years roasting ,5 in wood ovens , and all I know for sure is you have to adjust the grind [ and I cannot advise you enough that you have to have a burr type grinder] with every roast . But as in cooking you get to consume your mistakes.

[Rastys]

Fornax Hominus
I respect your credentials, and experience. I am a very newbie in comparison and need to get my act together for the event.
I have established after a lot of searching, reading and evaluating that I need to put the beans in at approx 200˚C, rotating them at around 50 to 60 rpm until the first cracking, then slow down the heating (if possible by either opening the door or sliding them out nearer the door) until they reach the start of the second cracking. I then plan on removing them (dumping them into a yet to be made tray that will fit into the top of a frame housing a good capacity fan), whilst still cracking and cool them to room temperature.
It is then advised to rest for between 3 to 5 days in a well ventilated cool area in plain calico bags, grind and brew. If the beans are a darker/espresso roast, then the post rest can be increased to 10 days before optimum taste and aroma.
How does this sound to you?

Cheers.

[Rastys]

fornax hominus
Yesterday, I made a tray to catch and to cool the beans when released from the roaster. I used the left over expanded metal to make a tray with top rolled edge 300mmw x 450mm long x 50mm high, It will easily slip through the front rotiserie support and under the roaster. All I need to make now is the fan forced cooling frame to sit the tray over and cool with a blast of cool air from under and above the hot beans.
Heat treated glass is cooled in the same way to make it tough and to shatter into thousands of little pieces as in automotive and shower screen/patio door glass (but not the laminated type).
I also bought home from the wrecking yard, a couple of notched gears from a 1500cc Mitsubishi Lancer engine complete with notched timing belt.
Under test this afternoon, it revolves at 30 rpm and could be slowed to almost zero if needed. I don't want it to rotate too fast as this would not allow the beans to cascade within the roasting bin. I can easily sped it up by increasing the size of the drive pulley on the wiper motor as I used the smallest that I could find.
This is to be my drive from a variable speed 12 volt windscreen wiper motor.
All I need too do now is to set it up in the oven and work out a way of tensioning the belt so that it tracks true and straight and maybe (if I need it) compensate for variable height of the rotating shaft, (mainly for the rotiserie function).
An electronics mate is building me a 240 volt power supply and variable speed controller.

[fornax hominus]

Lookin good!
When is your trial roast?
What beans do you have to roast? Although they sell beans just for espresso we have used beans from 4 continents with no problems .

[dmun]

I also bought home from the wrecking yard, a couple of notched gears from a 1500cc Mitsubishi Lancer engine complete with notched timing belt.

Will your timing belt put up with in-front-of-the-oven heat?