topbanner.gif
Login
Username

Password




Not a member yet?
Click here to register.

Forgotten your password?
Request a new one here.
Shoutbox
You must login to post a message.

11/25/2021 1:17 AM
JackedUp and CapnWhidbey, Welcome !

11/21/2021 1:56 AM
Welcome, pimaCanyon and Chris Porter!

11/18/2021 3:29 AM
locotoro, ionpau and gougege, welcome cup

11/16/2021 12:53 AM
RidgevilleRoaster OH, _lg3, Yirgaman, Houncer and AgressivStreetLamp
welcome !

11/15/2021 9:57 AM
Welcome, jasper_8137, goldyy9 and Evermancg !

In Memory Of Ginny
Donations

Latest Donations
JackH - 25.00
snwcmpr - 10.00
Anonymous - 2.00
Anonymous - 5.00
Anonymous - 5.00
Users Online
Guests Online: 12

Members Online: 0

Total Members: 7,359
Newest Member: JackedUp

View Thread

Who is here? 1 guest(s)
 Print Thread
Peferated or Solid Drum Roaster
beanflying
Hi all,

not sure if this has been discussed in recent times (tried search). Seems that most 2kg commercial drum roasters are running solid drums and having read Ringo & Boom's threads this seems a good way to go BUT.

I have been roasting on a Hottop for a fair while now which I suppose you call a Hybrid of sorts and it responds fairly well to heat changes if you lose your way be it power or fan due to the nature of the drum and low thermal mass.

Question is if I was to look at building a drum roaster around the 2kg mark, gas powered at this stage, to go solid, fully perforated or even partially perforated drum?

I have watched a fair few HG roasts recently and seen a few stall out (new operator) and no way really to recover them because the thermal inertia was lost and they weren't careful of the temp ramp. My thoughts are that from a chaff removal and heat response maybe a partially slotted drum might be the best of both worlds?

I also have a tame water jet cutter not far from me and I had planned to make the drum from 3-4mm rolled flat steel at this stage so the degree of drum airflow is easy to change while it is flat. Either that or a pipe section and a fair bit of milling will be needed.
Edited by beanflying on 04/28/2010 10:27 PM
My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
RoasterRob
Hi Tim

You do realise that 9 out of 10 solid drum roasters have a perforated rear plate. The air flows in thru the back and exits thru the front top bean inlet. There are very few completely solid (non perforated) drums. The only one that comes to mind is the Probat sample roaster, of which there was also a version with the rear plate perforated. If I was building one I would go solid drum and perf rear plate.
Hmm why am I saying If?

Rob
NZ
Edited by RoasterRob on 04/29/2010 1:38 AM
VBM Minimax 2gp, 1gp Reneka Techno, 2 gp la Pavoni Pub, la Cimbali M28, SJ Maz, FB 6kg HM roaster and other stuff
 
beanflying
Hi Rob,

yes I am familiar with the airflow on a solid drum roaster from rear to front and out. I guess I am looking at improving the thermal response time by allowing some heated air in the sides of the drum as well.

A solid drum certainly wins for simplicity but if I wanted simple I would just go out and buy one I guess ;)
My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
RoasterRob
Ok, from your post wasn't sure if you were aware of that. Not sure if there is any advantage in having perfs in the drum.
JMO though. I see you are relatively local. Usually have to wait till the next day to see replies from most of the other posters around here. ;)

Rob
NZ
VBM Minimax 2gp, 1gp Reneka Techno, 2 gp la Pavoni Pub, la Cimbali M28, SJ Maz, FB 6kg HM roaster and other stuff
 
beanflying
Yep just over here in Western New Zealand ;) Last time I was in your part of the Island good coffee was scarce, fixed that by drinking beer from a local Micro Brewery :)

Bit of a side issue to the perf or no perf thing I was looking at materials for drums and seems that 410 Stainless looks like a fairly good option for making drums. About the same characteristics as Carbon Steels and much better Thermal properties than the 300 series Stainless Steels, low thermal expansion as well. http://www.euro-i...ies_EN.pdf
Edited by beanflying on 04/29/2010 4:36 AM
My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
RoasterRob

Must have been a long time since your were in NZ, or you didn't get good advice on where to go for coffee.

I don't see any downside to using carbon steel. I have seen a vat for processing chocolate made in CS. Apparently as there is no water in the chocolate it doesn't rust.
A few of the FB air roasters I have built have had CS parts in contact with the beans. Although any air roasters I have built to on sell have had only SS in contact with the beans. For a drum roaster I would use CS for the drum. Much easier to work with and much cheaper.

Rob
NZ

VBM Minimax 2gp, 1gp Reneka Techno, 2 gp la Pavoni Pub, la Cimbali M28, SJ Maz, FB 6kg HM roaster and other stuff
 
Ringo
Good luck with your project, man a water jet would be nice. I am not sure what the best drum material is or how thick it should be, Mine is 1/4 thick and I feel like it would be better if it was thinner, but only ran it one time. On air flow I use a 3" piece of steel conduit to vent my roaster and I feel like I have extra, better to have too much so you can cut it back as needed. In my 8" dia drum I put two rows of stirring veins, one forward one reverse. With the drum running 60 rpm these stir the air a lot and keep the beans in the air alot. I mostly do drip so I did not want a traditional drum profile, I believe my coffee will be a hybrid not quite as bright as a air roaster but not as full as a drum roast. This is my goal anyway. I am a builder kind of guy not to good with written works but what I am trying to say is I think the stirring of the veins give you a lot of air contact time with the beans. I have not posted any pictures yet, trying to get finished before. If you get to the planning stage on you bean cooler drop me a note, I used a stainless steel stock pot with a been stirrer, dump gate coming out nice. On the stalls, I believe if I see a stall I will be able to kick up the burners and the air and get the ET up fast. As I read stuff from these old roasters they say the important thing is how many BTU's you imput. I think you only want the steel mass to do the early stages of roasting {controlled by drop temp} them you want to roast with the Air Tempature or {ET}. I am no expert, only roasted on a drum 1 time in my life, just trying to give you an look at my design thoughts for my roaster after a lot of reading. I HOPE I am right.

Thanks
Ringo
Edited by Ringo on 04/29/2010 6:31 AM
 
beanflying
8 or 9 years since I was in Christchurch, so a bit better by now I am sure. Misbehaved badly last time I was there so good memories or at least the ones I remember ;)

Only downside to Carbon Steels is I live 200m from the Southern Ocean so salt air is a consideration, as it seems 410 is about as good as CS it is worth the price I think. The old rule of Steel x 4 to get to Stainless Steel is a bit ordinary but worth it for longevity and having to drop the drum out to remove rust would be a pain.

3-4mm sounds about right for material thickness for the drum. Needs to be thick enough so it won't distort when getting welded or in use and not to thick so the working Temperature can be changed in reasonable time? I am with you on airflow it can always be choked back.


My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
Ringo
One more thing to think with the stainless is the add cost to weld, I can not tig so I used stick. I buy my stainless rods 5 at the time and they are $12. Welds great but get expensive. You can weld with standard rod but the seam can rust. In your case if this will work out I would use stainless. I do not believe the bean side will ever rust, the oils out of the bean will protect that but the fire side will be unprotected.

Ringo
 
dja

Quote

Ringo wrote:
I buy my stainless rods 5 at the time and they are $12. Ringo



heck Ringo you should of said something I just gave a buddy about 40 lbs of 310.16 stainless rod
I pour Iron and roast Coffee BeansThumbsUp
If life seems normal your not going fast enough Mario Andrette
 
dja
at the your rate of 12.00 bucks for 5 rods thats what a thousand bucks worth
I pour Iron and roast Coffee BeansThumbsUp
If life seems normal your not going fast enough Mario Andrette
 
beanflying
Hi dja

what Ringo is talking about is Arc welding Rods so flux covered not straight Stainless rod. If you buy them in 1kg or 2.5kg packs they are a lot cheaper than the $12/5. As to welding my own not going to happen either, I know a guy who builds speedway chassis for a living.

Even though the plan is to build an own design roaster I figured out a long time ago that it was far better to use professional skills and tools to my plans or designs and do the fiddly assembly work myself. If you consider a Tig welder to do this sort of work at $3k+ you can buy a lot of welding time for a small portion of that ;) Same thing goes for guillotines, benders, plasma or water jet cutters.
Edited by seedlings on 04/29/2010 10:02 PM
My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
beanflying
Just to fess up here I have finished up 2 years later woosing out on building my own and brought a 1kg Taiwanese electric with a slotted stainless drum.

Some details and discussion of it here http://www.bestca...e-roaster/

The reason for the not rolling my own simply a lack of time in my life and the manufacturing costs looked like blowing out toward the cost of the above roaster.

lh4.googleusercontent.com/-nxDKOzwct3g/T8Md3ysxnHI/AAAAAAAAAjA/hOIUfRRGC-Y/s800/1kg+out+of+the+crate.jpg

So just to sort of tie u this topic I am dealing with a perforated 10"x10" drum on this roaster. Only one roast down but so far so good :)
My name is Tim and I have a coffee equipment addiction problem :)

Two Hottops - modded
TJ 067 Electric 1kg 5+years old
Insert new 5-8kg Roaster here urgently BBQ grill
 
Jump to Forum:

Similar Threads

Thread Forum Replies Last Post
Fluidbed Roaster project Fluidbed Roaster 136 11/25/2021 11:53 AM
1/2 lb - Heat Gun Element - Tc4+ - Fluidbed Roaster Fluidbed Roaster 1 11/24/2021 2:55 PM
"Well tempered roaster" more feedback Roasting Coffee 24 11/23/2021 7:27 PM
New Fluid bed roaster- Design and modifications Fluidbed Roaster 12 11/23/2021 1:15 PM
My first (real) roaster MY FIRST ROASTER 19 11/22/2021 11:29 AM
Homeroasters Association Logo, and all Content, Images, and Icons © 2005-2016 Homeroasters Association - Logos are the property of their respective owners.
Powered by PHP-Fusion Copyright © 2021 PHP-Fusion Inc
Released as free software without warranties under GNU Affero GPL v3
Designed with by NetriX