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Date: 18 Nov 2006 10:39:22
From: espressoMarv
Subject: aluminum drum for small home roaster ?? will AL work??
Hello,

I am new to the group - HI!

I am planning on trying to build a very small (1/2 pound) roaster. I
have noticed that no one uses an aluminum drum. Why is that? Would the
beans char on the outside?or?? Any incites greatly appreciated.

Thank you

vin

a little about me
I drink mostly espresso, americanos and french press. there is no good
roaster in my area and really I want to tinker and learn to roast both
for self satisfaction and palate development. I have had many great
espressos/coffees in my pilgrimages to Seattle, Portland and Vancouver.
I have been developing my skills as a Barista at home and running a
once a week espresso stand at a local Outdoors farmers ket in the
summer months for the past two years. I had coffee shipped in weekly
from JJBean in Vancouver.





 
Date: 24 Nov 2006 15:32:18
From: espressoMarv
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Thank you all for the replies - steel it is.

vin

On Nov 18, 11:39 am, "espressov" <espressom...@gmail.com > wrote:
> Hello,
>
> I am new to the group - HI!
>
> I am planning on trying to build a very small (1/2 pound) roaster. I
> have noticed that no one uses an aluminum drum. Why is that? Would the
> beans char on the outside?or?? Any incites greatly appreciated.
>
> Thank you
>
> vin
>
> a little about me
> I drink mostly espresso, americanos and french press. there is no good
> roaster in my area and really I want to tinker and learn to roast both
> for self satisfaction and palate development. I have had many great
> espressos/coffees in my pilgrimages to Seattle, Portland and Vancouver.
> I have been developing my skills as a Barista at home and running a
> once a week espresso stand at a local Outdoors farmers ket in the
> summer months for the past two years. I had coffee shipped in weekly
> from JJBean in Vancouver.



 
Date: 24 Nov 2006 07:23:21
From: espressoMarv
Subject: Re: aluminum drum for small home roaster ?? will AL work??
thank you all for the replies.

I do have another question though. What is the ideal material for a
drum and why? Many like cast iron in the older Probats versus the high
carbon steel found in say a Dietrich. Why is that? Does cast iron keep
its heat better than carbon steel? I guess what I am asking is Do you
want the metal of the drum to easily give up heat (aluminum) or not
very easily? or is there another reason for the chosen metals besides
the strength factor of Aluminum?

Thank you

vin

On Nov 18, 11:39 am, "espressov" <espressom...@gmail.com > wrote:
> Hello,
>
> I am new to the group - HI!
>
> I am planning on trying to build a very small (1/2 pound) roaster. I
> have noticed that no one uses an aluminum drum. Why is that? Would the
> beans char on the outside?or?? Any incites greatly appreciated.
>
> Thank you
>
> vin
>
> a little about me
> I drink mostly espresso, americanos and french press. there is no good
> roaster in my area and really I want to tinker and learn to roast both
> for self satisfaction and palate development. I have had many great
> espressos/coffees in my pilgrimages to Seattle, Portland and Vancouver.
> I have been developing my skills as a Barista at home and running a
> once a week espresso stand at a local Outdoors farmers ket in the
> summer months for the past two years. I had coffee shipped in weekly
> from JJBean in Vancouver.



  
Date: 24 Nov 2006 19:04:37
From: Andy Schecter
Subject: Re: aluminum drum for small home roaster ?? will AL work??
espressov wrote:
> What is the ideal material for a
> drum and why? Many like cast iron in the older Probats versus the high
> carbon steel found in say a Dietrich. Why is that? Does cast iron keep
> its heat better than carbon steel? I guess what I am asking is Do you
> want the metal of the drum to easily give up heat (aluminum) or not
> very easily? or is there another reason for the chosen metals besides
> the strength factor of Aluminum?


Coffee roasters operate at (or very near) the temperature range where aluminum
begins to change its physical properties. In other words, the strength,
hardness, etc of aluminum will change as a result of the roasting process.

As Ed pointed out, this is probably not a problem for a lightly used home
roaster. But for long term commercial/industrial roaster use, aluminum is
inappropriate. No responsible manufacturer would take a chance on warrantying
it. And besides, they wouldn't want to pay premium prices for buying and
welding it in the first place.


--


-Andy S.

http://www.flickr.com/photos/andy_s/sets/


  
Date: 24 Nov 2006 13:50:25
From: Ed Needham
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Here's the easy answer...
It's all about personal preference.
Also,
Typical roaster drums are made from all types of materials. Some commercial
drums are stainless, perforated, cast, steel, and who knows what else.
Each roaster will give it's own nuance of roast to the beans. Finding a
roaster you like is probably like finding a good partner...very difficult.
I have had better luck finding a roaster that does a decent job on beans
than in finding a good partner though, so don't give up hope. My preference
is a thin walled, perforated stainless steel drum. That setup allows me to
vary temps quickly for profile roasting. A thicker drum with a larger load
is much slower to turn, like a big semi truck vs. a little quick sports car.
I can roast five pound batches and that's just about right for me.

--
*********************
Ed Needham®
"to absurdity and beyond!"
http://www.homeroaster.com
(include [FRIEND] in subject line to get through my SPAM filters)
*********************


"espressov" <espressov@gmail.com > wrote in message
news:1164381801.378905.91200@f16g2000cwb.googlegroups.com...
> thank you all for the replies.
>
> I do have another question though. What is the ideal material for a
> drum and why? Many like cast iron in the older Probats versus the high
> carbon steel found in say a Dietrich. Why is that? Does cast iron keep
> its heat better than carbon steel? I guess what I am asking is Do you
> want the metal of the drum to easily give up heat (aluminum) or not
> very easily? or is there another reason for the chosen metals besides
> the strength factor of Aluminum?
>
> Thank you
>
> vin




   
Date: 24 Nov 2006 18:09:31
From: Ed Needham
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Let me clarify...
"...much slower to turn temperatures around."
"Ed Needham" <ed@NOSPAMhomeroaster.com > wrote in message
news:SdmdndUPIv9Fo_rYnZ2dnUVZ_oednZ2d@insightbb.com...
<SNIP > A thicker drum with a larger load
> is much slower to turn, like a big semi truck vs. a little quick sports
> car.
<SNIP >




  
Date: 24 Nov 2006 17:21:57
From: The Other Funk
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Finding the keyboard operational
espressov entered:

> thank you all for the replies.
>
> I do have another question though. What is the ideal material for a
> drum and why? Many like cast iron in the older Probats versus the high
> carbon steel found in say a Dietrich. Why is that? Does cast iron keep
> its heat better than carbon steel? I guess what I am asking is Do you
> want the metal of the drum to easily give up heat (aluminum) or not
> very easily? or is there another reason for the chosen metals besides
> the strength factor of Aluminum?
>
> Thank you
>
> vin
>
By no means is this a scientific answer but I believe you want a drum that
will slowly dissipate heat. You will see a significant drop from your
preheated drum when you first add beans, A denser material will not drop as
much.
Another reason I believe a denser material is used is to prevent wwarping
when the drum is cooling down after roasting. Once you are finished appling
heat you want the drum to be as isothermal as possible while it returns to
room temp. If your drum was unevenly cooled, you might end up with an out of
round drum. At the very least you would be introducing stresses with the
uneven cooling. Again, as a guess, aluminum will fatigue faster then a steel
or iron drum.
Bob
--
--
Coffee worth staying up for - NY Times
www.moondoggiecoffee.com



 
Date: 22 Nov 2006 11:14:09
From: espressoMarv
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Hi Ed,

thankd for the reply.

Do you have any experience with aluminum? some have mentioned corrosion
issues if I used aluminum - any thoughts

Thank you

vin

On Nov 21, 1:56 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com > wrote:
> I've made several solid walled drums and roasted beans with them. No blo=
wer
> necessary. The agitation and rotation of the drum within the roaster
> environment are all you need to roast beans. Adding a heat gun would be =
an
> interesting experiment, but don't think you have to do it to get a good
> roast.http://www.homeroaster.com/tinydrum.html
> --
> *********************
> Ed Needham=AE
> "to absurdity and beyond!"http://www.homeroaster.com
> (include [FRIEND] in subject line to get through my SPAM filters)
> *********************
>
> "espressov" <espressom...@gmail.com> wrote in messagenews:1164129549.7=
36231.110850@j44g2000cwa.googlegroups.com...
>
> > I am not planning on using conduction alone - I plan to have a heat gun
> > pointing in from the back of the drum for airflow and heat adjustment.
> <SNIP>
>
> > On Nov 21, 8:48 am, "Jack Denver" <nunuv...@netscape.net> wrote:
> >> Conduction from a solid drum is probably the worst (most uneven)
> >> possible
> >> roasting method<SNIP>



  
Date: 22 Nov 2006 22:58:59
From: Ed Needham
Subject: Re: aluminum drum for small home roaster ?? will AL work??
I don't like aluminum, and I'm a big fan of working with stainless, but many
have bought that funky perfed sheet aluminum from the hardware store and
made workable drums out of it. The case of my grill is aluminum and it does
not seem to be getting weaker by the moment as some have predicted about
aluminum drums. If you make one from aluminum, I'd bet it will work fine.
If not, then what have you really lost? Aluminum is really cheap.

--
*********************
Ed Needham®
"to absurdity and beyond!"
http://www.homeroaster.com
(include [FRIEND] in subject line to get through my SPAM filters)
*********************

"espressov" <espressov@gmail.com > wrote in message
news:1164222849.923762.288840@m7g2000cwm.googlegroups.com...
Hi Ed,

thankd for the reply.

Do you have any experience with aluminum? some have mentioned corrosion
issues if I used aluminum - any thoughts

Thank you

vin




   
Date: 22 Nov 2006 23:29:27
From: Jack Denver
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Grill cases are made of thick cast aluminum, not perforated sheet metal.
They do corrode in the long run - my inlaw's old grill rotted thru at the
bottom and broke free of it's post (but it must have been a good 20 yrs.
old, so it didn't owe them anything).

I doubt corrosion would be a problem in the short run. Coffee is not very
corrosive and the oils tend to form a protective coating on the metal.


"Ed Needham" <ed@NOSPAMhomeroaster.com > wrote in message
news:rsadnT-WP9nugfjYnZ2dnUVZ_qydnZ2d@insightbb.com...
>I don't like aluminum, and I'm a big fan of working with stainless, but
>many have bought that funky perfed sheet aluminum from the hardware store
>and made workable drums out of it. The case of my grill is aluminum and it
>does not seem to be getting weaker by the moment as some have predicted
>about aluminum drums. If you make one from aluminum, I'd bet it will work
>fine. If not, then what have you really lost? Aluminum is really cheap.
>
> --
> *********************
> Ed Needham®
> "to absurdity and beyond!"
> http://www.homeroaster.com
> (include [FRIEND] in subject line to get through my SPAM filters)
> *********************
>
> "espressov" <espressov@gmail.com> wrote in message
> news:1164222849.923762.288840@m7g2000cwm.googlegroups.com...
> Hi Ed,
>
> thankd for the reply.
>
> Do you have any experience with aluminum? some have mentioned corrosion
> issues if I used aluminum - any thoughts
>
> Thank you
>
> vin
>
>




 
Date: 21 Nov 2006 09:19:09
From: espressoMarv
Subject: Re: aluminum drum for small home roaster ?? will AL work??

Thank you for the replies

I am not planning on using conduction alone - I plan to have a heat gun
pointing in from the back of the drum for airflow and heat adjustment.

from hearing the replies my newest thought is to have a thing stainless
drum wrapped on the outside with aluminum for heat conductivity.

with regards to heating the beans directly with a ceramic infrared
heater would take too long for the roast to develop. Any thoughts. I
was planning on painting the drum with BBQ paint sothe drum would
efficiently take on the heat. Any thoughts.

vin


On Nov 21, 8:48 am, "Jack Denver" <nunuv...@netscape.net > wrote:
> Conduction from a solid drum is probably the worst (most uneven) possible
> roasting method and none of the modern commercial roasters rely on
> conduction alone. Good luck with this approach - you'll need it. It's good
> to try new approaches but people have been working on coffee roasting
> machinery for at least the last 150 years and most "new" approaches are
> really "old" approaches that have been rejected for good reason("infrared"
> doesn't count as new - glowing coals are also "infrared" heaters).
>
> There is nothing wrong with an aluminum drum per se but it's not used
> commercially due to the issues mentioned in the thread - cost, difficulty of
> working, lack of strength esecially when perforated, etc. There's really no
> reason why you couldn't use it in a home rig. The "you'll poison yourself
> with aluminum" people are cranks - aluminum is used as cookware by millions
> of beople and the scientific consensus is that it's safe. I would not make
> a drum from galvanized steel, which is common form of sheet metal that you
> might be tempted to use - zinc fumes are not good for you.
>
> "espressov" <espressom...@gmail.com> wrote in messagenews:1164068123.857782.173710@m73g2000cwd.googlegroups.com...
>
> > Yes I was thinking a non-perforated drum. Aluminum because it is
> > lighter to support as a cantilever- so I would not have to have a
> > support at the front where I want to be able to dump the beans. Also I
> > am planning on using an infrared heater and this way the beans would
> > not be subject to the infrared directly possibly resulting in scorch
> > ks on the outside of the beans.
>
> > any thoughts appreciated.
>
> > vin
> > On Nov 19, 7:35 pm, "rasqual" <scott.qua...@gmail.com> wrote:
> >> If you wanted a non-perforated drum, aluminum could, in theory, be a
> >> candidate. But if you're wanting to use some kind of mesh, aluminum is
> >> terrible. Weak! In order to get the strength you'd need with a 50% or
> >> better open area, you'd need such high grade aluminum that the cost
> >> would make stainless steel look like a bargain.
>
> >> - Scott
>
> >> On Nov 18, 12:39 pm, "espressov" <espressom...@gmail.com> wrote:
>
> >> > Hello,
>
> >> > I am new to the group - HI!
>
> >> > I am planning on trying to build a very small (1/2 pound) roaster. I
> >> > have noticed that no one uses an aluminum drum. Why is that? Would the
> >> > beans char on the outside?or?? Any incites greatly appreciated.



  
Date: 21 Nov 2006 15:56:55
From: Ed Needham
Subject: Re: aluminum drum for small home roaster ?? will AL work??
I've made several solid walled drums and roasted beans with them. No blower
necessary. The agitation and rotation of the drum within the roaster
environment are all you need to roast beans. Adding a heat gun would be an
interesting experiment, but don't think you have to do it to get a good
roast.
http://www.homeroaster.com/tinydrum.html
--
*********************
Ed Needham®
"to absurdity and beyond!"
http://www.homeroaster.com
(include [FRIEND] in subject line to get through my SPAM filters)
*********************

"espressov" <espressov@gmail.com > wrote in message
news:1164129549.736231.110850@j44g2000cwa.googlegroups.com...
>
> I am not planning on using conduction alone - I plan to have a heat gun
> pointing in from the back of the drum for airflow and heat adjustment.
<SNIP >
>
>
> On Nov 21, 8:48 am, "Jack Denver" <nunuv...@netscape.net> wrote:
>> Conduction from a solid drum is probably the worst (most uneven)
>> possible
>> roasting method
<SNIP >




  
Date: 21 Nov 2006 10:18:28
From: Randy G.
Subject: Re: aluminum drum for small home roaster ?? will AL work??
I would avoid the aluminum all together unless you are just building a
prototype to test your design. Just make the drum out of steel or
stainless steel. As far as the external heating, why? Your goal is to
heat the beans, not the drum. You want to envelop each bean with the
heat energy. Depending on the drum to transfer heat to the beans
through conduction is a misconceived design. I would leave as little
air space around the drum as possible, insulate that area to hold in
the heat, and just use the heat gun. There was a Jabez Burns roaster
that shot the gas flame right through the center of the drum and the
beans tumbled around the flame. There are quite a few of them still in
use today. Also make sure you have a way to quickly remove and cool
the beans.


Randy "reinventing the wheel" G.
http://www.EspressoMyEspresso.com



"espressov" <espressov@gmail.com > wrote:
>
>Thank you for the replies
>
>I am not planning on using conduction alone - I plan to have a heat gun
>pointing in from the back of the drum for airflow and heat adjustment.
>
>from hearing the replies my newest thought is to have a thing stainless
>drum wrapped on the outside with aluminum for heat conductivity.
>
>with regards to heating the beans directly with a ceramic infrared
>heater would take too long for the roast to develop. Any thoughts. I
>was planning on painting the drum with BBQ paint sothe drum would
>efficiently take on the heat. Any thoughts.
>


 
Date: 20 Nov 2006 20:49:20
From: rasqual
Subject: Re: aluminum drum for small home roaster ?? will AL work??
On Nov 20, 6:15 pm, "espressov" <espressom...@gmail.com > wrote:
> Yes I was thinking a non-perforated drum. Aluminum because it is
> lighter to support as a cantilever- so I would not have to have a
> support at the front where I want to be able to dump the beans. Also I
> am planning on using an infrared heater and this way the beans would
> not be subject to the infrared directly possibly resulting in scorch
> ks on the outside of the beans.

I'd say go with an infrared heater right inside the bloomin' drum.

Seriously.

As long as you're not right up against the beans, and as long as
they're agitating properly, this would probably yield a better roast
than relying on pure conduction heat transfer to the beans via
aluminum.

Full disclosure: I've long been superstitiously suspicious of
conduction as a predominant transfer mechanism in roasting.

- S



 
Date: 20 Nov 2006 16:15:24
From: espressoMarv
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Yes I was thinking a non-perforated drum. Aluminum because it is
lighter to support as a cantilever- so I would not have to have a
support at the front where I want to be able to dump the beans. Also I
am planning on using an infrared heater and this way the beans would
not be subject to the infrared directly possibly resulting in scorch
ks on the outside of the beans.

any thoughts appreciated.

vin
On Nov 19, 7:35 pm, "rasqual" <scott.qua...@gmail.com > wrote:
> If you wanted a non-perforated drum, aluminum could, in theory, be a
> candidate. But if you're wanting to use some kind of mesh, aluminum is
> terrible. Weak! In order to get the strength you'd need with a 50% or
> better open area, you'd need such high grade aluminum that the cost
> would make stainless steel look like a bargain.
>
> - Scott
>
> On Nov 18, 12:39 pm, "espressov" <espressom...@gmail.com> wrote:
>
> > Hello,
>
> > I am new to the group - HI!
>
> > I am planning on trying to build a very small (1/2 pound) roaster. I
> > have noticed that no one uses an aluminum drum. Why is that? Would the
> > beans char on the outside?or?? Any incites greatly appreciated.



  
Date: 21 Nov 2006 10:48:10
From: Jack Denver
Subject: Re: aluminum drum for small home roaster ?? will AL work??
Conduction from a solid drum is probably the worst (most uneven) possible
roasting method and none of the modern commercial roasters rely on
conduction alone. Good luck with this approach - you'll need it. It's good
to try new approaches but people have been working on coffee roasting
machinery for at least the last 150 years and most "new" approaches are
really "old" approaches that have been rejected for good reason("infrared"
doesn't count as new - glowing coals are also "infrared" heaters).

There is nothing wrong with an aluminum drum per se but it's not used
commercially due to the issues mentioned in the thread - cost, difficulty of
working, lack of strength esecially when perforated, etc. There's really no
reason why you couldn't use it in a home rig. The "you'll poison yourself
with aluminum" people are cranks - aluminum is used as cookware by millions
of beople and the scientific consensus is that it's safe. I would not make
a drum from galvanized steel, which is common form of sheet metal that you
might be tempted to use - zinc fumes are not good for you.



"espressov" <espressov@gmail.com > wrote in message
news:1164068123.857782.173710@m73g2000cwd.googlegroups.com...
> Yes I was thinking a non-perforated drum. Aluminum because it is
> lighter to support as a cantilever- so I would not have to have a
> support at the front where I want to be able to dump the beans. Also I
> am planning on using an infrared heater and this way the beans would
> not be subject to the infrared directly possibly resulting in scorch
> ks on the outside of the beans.
>
> any thoughts appreciated.
>
> vin
> On Nov 19, 7:35 pm, "rasqual" <scott.qua...@gmail.com> wrote:
>> If you wanted a non-perforated drum, aluminum could, in theory, be a
>> candidate. But if you're wanting to use some kind of mesh, aluminum is
>> terrible. Weak! In order to get the strength you'd need with a 50% or
>> better open area, you'd need such high grade aluminum that the cost
>> would make stainless steel look like a bargain.
>>
>> - Scott
>>
>> On Nov 18, 12:39 pm, "espressov" <espressom...@gmail.com> wrote:
>>
>> > Hello,
>>
>> > I am new to the group - HI!
>>
>> > I am planning on trying to build a very small (1/2 pound) roaster. I
>> > have noticed that no one uses an aluminum drum. Why is that? Would the
>> > beans char on the outside?or?? Any incites greatly appreciated.
>




 
Date: 19 Nov 2006 18:35:22
From: rasqual
Subject: Re: aluminum drum for small home roaster ?? will AL work??
If you wanted a non-perforated drum, aluminum could, in theory, be a
candidate. But if you're wanting to use some kind of mesh, aluminum is
terrible. Weak! In order to get the strength you'd need with a 50% or
better open area, you'd need such high grade aluminum that the cost
would make stainless steel look like a bargain.

- Scott

On Nov 18, 12:39 pm, "espressov" <espressom...@gmail.com > wrote:
> Hello,
>
> I am new to the group - HI!
>
> I am planning on trying to build a very small (1/2 pound) roaster. I
> have noticed that no one uses an aluminum drum. Why is that? Would the
> beans char on the outside?or?? Any incites greatly appreciated.



 
Date: 19 Nov 2006 12:47:03
From: Ist-e Mundus, Furia bundus
Subject: Re: aluminum drum for small home roaster ?? will AL work??

"espressov" <espressov@gmail.com > wrote in message
news:1163875162.467509.196300@m73g2000cwd.googlegroups.com...
> Hello,
>
> I am new to the group - HI!
>
> I am planning on trying to build a very small (1/2 pound) roaster. I
> have noticed that no one uses an aluminum drum. Why is that? Would the
> beans char on the outside?or?? Any incites greatly appreciated.
>
> Thank you
>
> vin
>
> a little about me
> I drink mostly espresso, americanos and french press. there is no good
> roaster in my area and really I want to tinker and learn to roast both
> for self satisfaction and palate development. I have had many great
> espressos/coffees in my pilgrimages to Seattle, Portland and Vancouver.
> I have been developing my skills as a Barista at home and running a
> once a week espresso stand at a local Outdoors farmers ket in the
> summer months for the past two years. I had coffee shipped in weekly
> from JJBean in Vancouver.


Although it would probably be a minute amount, I would tend to stay away
from anything that could add aluminum to something I consume. Aluminum does
not hold heat particularly well, so perhaps a stable, consistent temperature
is not as easy to achieve. It would heat up quickly, but be more easily
affected by ambient temperature. Also, at high temperatures, it would be far
more prone to corrosion.

Just some random thoughts!





 
Date: 18 Nov 2006 19:21:14
From: Ian Smith
Subject: Re: aluminum drum for small home roaster ?? will AL work??
On 18 Nov 2006 10:39:22 -0800, espressov <espressov@gmail.com > wrote:
> Hello,
>
> I am new to the group - HI!
>
> I am planning on trying to build a very small (1/2 pound) roaster. I
> have noticed that no one uses an aluminum drum. Why is that? Would the
> beans char on the outside?or?? Any incites greatly appreciated.

More difficult to join (ie, tricky welding, softer so mechanical
fastening less straightforward)?

More expensive?

Higher heat of doodah, so takes more energy to get the temperatures
you want?

Less easy to make fine mesh?

No real benefit over steel?

All speculation, but plausible.

regards, Ian SMith
--