Not a member yet?
Click here to register.

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

10/19/2021 6:22 AM
Welcome tarunk!

10/17/2021 12:40 PM
Ploni and nader fouad, Welcome!

10/15/2021 2:19 AM
merlot85, maycondelpiero and hoeltz, Welcome !

10/14/2021 10:06 AM
Thanks for the addition to the group. Seriously considering building a drum roaster along the lines of oldgrumpus's. Love the design and craftsmanship.

10/14/2021 4:00 AM
Morning, ar3mia ! and... coffee drink

In Memory Of Ginny

Latest Donations
JackH - 25.00
snwcmpr - 10.00
Anonymous - 2.00
Anonymous - 5.00
Anonymous - 5.00
Users Online
Guests Online: 24

Members Online: 0

Total Members: 7,363
Newest Member: tarunk

View Thread

Who is here? 1 guest(s)
 Print Thread
1 to 3 lb roaster build
I'm gathering parts and ideas for building a RR style roaster. I've worked my way through a popcorn popper, stir crazy, bread machine/heat gun, Behmoor and Huky over the past 8 years. I enjoy roasting with the Huky, but my older model tops out at about 325gms. I'd like to build a RR style furnace with a couple different roast chambers for 1lb and 3lb roasted batches and I need some advice. What sizes of chambers would be best for those size batches. 4" for the 1lb batch? I figure I'll build the furnace with 6" ID steel as I've seen suggested for sufficient airflow not to blow out the Sievert 2941 or 2942 burner. How long should the furnace section be to make sure the flame doesn't reach the roast chamber? I bought an Amtek blower and I don't know if I got a dud or if they're all that loud. I measured 115 db when my shop vac only measures 92db. I'm not sure if you can insulate and bring that much noise down enough to hear cracks? I may be searching for a quieter option. Last question I can think of is about a sight glass option to see the burner flame. Does the glass need to be borosilicate or otherwise. I'm sure standard window glass will quickly crack. Thanks for any and all help and suggestions. I will post pictures of my progress when it gets rolling. Thanks.
Close subject discussed yesterday here:
DIY: TO based IR 750g
Moded commercial: Dieckmann RoestMeister, Nesco, popper(s).
TC4ESP, MS6514, USB/Artisan/Apps, PID controllers
Grinder: MBK Feldgrind, mod'ed Porlex to 47 conical burrs, vintage PeDe Dienes, Kinu M38
Gaggia Mini, Aeropress, drip
Borosilicate is probably best but Iíve read that normal glass can be used. Iím going to try a 5.5Ē glass roast chamber using a tube I made from a large glass vase.
Coleman or similar lantern globles are approx. 5 1/2" in diameter. those are usually less that $10 and if you are handy, you can make a ring that will let you stack them.
That's where having a lath or friend with one is great. I'm using some pieces of 6" square aluminum plate to make a top, bottom and center ring to stack them, and high temp, food grade, silicon to seal everything together. Four 1/4" rods in each corner will keep everything together.
Stacking a couple of Coleman lantern globes would definitely be a cheaper glass option than I was like okíing at. I appreciate the advice. Iím going to try and build an enclosure for my blower first and see how much that reduces the sound.
I've just powered my new 600W vacuum blower on full power and the noise is also very loud! I use the same motor on my smaller roaster but never run it over 25% so it's much quieter at that speed.

Will you be running at 100% fan speed?
Iím sure I wonít need more than 50%, and my test was at full speed. I would like it to be as quiet as possible though. Iím getting ready to order my Sievert parts. Do I need the handle? I figured Iíd get a 0-60 regulator with good control and forego the handle.
Any suggestions on how long of a pipe to use for the furnace section? I saw that Rob said 6"ID is a good size to keep from blowing out the flame and allows for many different size roasting chambers to sit on top. I just don't know how long to make the section. I'm assuming if it's too long you lose a bit of heat and if it's too short you can scorch the beans. From videos and pictures I've seen it looks like maybe a 2 to 3 foot section?
If you are potentially running a 2942 I would not be worried about the minute heat loss from a longer tube. With a preheat it would be extremely minimal and the 2942 throws a ton of heat. I don't think I would even be worried about heat loss with a 2941 for those bean volumes. A longer FC allows more time for the heat to mix and less chance of overheating the center of the plate.

If it were me I would make the FC as long as I could before the height just became a logistical issue with the roast area/storage area for the roaster.

"Tis easier to remove metal than add metal" - anonymous
Honey badger 1k, Bunn LPG-2E, Technivorm, Cimbali Max Hybrid, Vibiemme Double Domo V3
If you thing one is noisy, you should hear 12 of them running at once. Years back when I built my flow bench, they were in it, It wasn't long before a made a sepate box and remoted the motor away from it. Made a huge difference. I plan to do the same thing on the roaster I'm building. With the motor right there with the roaster, I would never hear any of the cracks.
I bought a router speed controller for my blower and was surprised it only decreases the air volume a slight bit from the highest to lowest setting. Would a variac work better, or would turning to a low voltage be hard on the motor? With this setup, Iíll probably have to create a bleed off valve to dump some of the air volume.


Would a variac work better, or would turning to a low voltage be hard on the motor? With this setup, Iíll probably have to create a bleed off valve to dump some of the air volume.

Maybe hearing a real world example might help. I roasted twice/wk for 19 years using a vacuum blower at around 20% power using a variac without issue. I, like you, didn't need anywhere near the rated capacity. It has been reported that they will run slightly hotter when not running full tilt so you may end up getting 20 years instead of 30 by slowing it down and saving your ear drums. Small price to pay for the improved ear heath. If you need to reduce power level below what the router speed controller will afford then go for a variac but don't worry about wearing out the vacuum blower.

1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
I appreciate that information, allenb. I do have a 3amp variac that immediately blew the fuse when I turned it on. I'll order a 20 amp version off ebay. I don't completely understand the circuitry of the router speed controller but it must let the device plugged into it still pull the minimum voltage it wants to pull rather than limiting the voltage to an exact amount like the variac?
Since they operate in some form or fashion to produce a "chopped" quasi sinusoidal output, they have limitations in how low in power they can go and still produce a waveform that can be tolerated by a universal AC/DC motor. The variac on the other hand, being an autotranformer can take the voltage all the way to zero.

I used a 3 amp variac on a 600 watt vacuum blower with no over heating issues but mine was not fused and if it had been, would most likely have gone over the 3 amp rating and popped. While roasting near a 1 lb batch (fluidbed), it never topped 4 amps. If you can find one, an 8 or 10 amp rated variac should be more than enough for your roaster and would most likely cost much less.
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
I have experimented with 3 different drives for my one pound fluid- bed roaster. The two-stage vac motor can run to 8 amps on different devices.
1) Router controller - would not turn down enough and drew the most current.
2) Single board DC drive - Lots of adjustments to work with, the fine control of vac speed is better than router control.
3) Ten-amp Variac - The best and lowest current draw. Usually runs at 3 amps and only goes up to 6 when a big change in speed has been ordered. However they are bigger, and more expensive than the other two methods I tried.
No oil on my beans...
I bought a 20 amp Chinese variac off eBay. Man that thing is huge! Works great, though. Now I can really turn down my blower thatís overpowered for my first build. Now to source parts for the furnace section. Iím going to follow Robís 6Ē ID steel design that he says he used for his 1 pounder and later much larger. Iíd like to have a chamber for 1lb test batches and another that will do 2 or 3 lbs at a time. Are the Pyrex bake a roundís large enough for a roasted pound, or not quite?
Edited by Huky531 on 02/19/2018 9:05 PM
Absolutely! The upper limit of my Bakearound was 600g (in my FB roaster at least) before I started shooting beans into my chaff collector at the end of the roast.

I usually roast 500-550g loads no problem. However, sometimes with larger beans it gets a little dicey :-)
Finally advanced some on the roaster build. Found a 2.5ft 6"ID steel pipe section and cleaned it up for my furnace section. I also built a box around my blower motor to quiet it down, and it makes a huge difference. The box drops it from 115db to more like 78db at full blast and probably more like 68db at the useable airflow for my roast sizes. I also got my 2941 and bought a die off ebay/china to thread a pipe for it. Hopefully I'll speed up the process of my build from now on.
Not sure why it wonít let me add pictures. Iíve tried both from the computer and my smartphone.
Are you getting an error message?

The attachment file size limit is 10MB, should be more than enough for computer viewing. 8 images can be uploaded.

Select your files using the Browse button at the bottom of the edit post screen:

The site is Linux based. Try not use any Linux reserved characters in your file name. I also avoid using spaces in the file name. Try to keep the file name as short as possible:

Allowed file types for all types of attachments are:
.gif .jpg .png .zip .rar .tar .7z

Please contact me if you are still having trouble.
JackH attached the following images:
reserved.jpg browse.jpg

Edited by JackH on 03/13/2018 7:21 AM

KKTO Roaster.
Jump to Forum:

Similar Threads

Thread Forum Replies Last Post
"Well tempered roaster" more feedback Roasting Coffee 21 10/14/2021 6:26 AM
New Fluid bed roaster- Help with how to control it Fluidbed Roaster 5 10/12/2021 1:34 PM
Using a TC4 with Artisan Roaster Scope Dataloggers/Controllers/Rate of Rise Meters 28 10/10/2021 10:41 PM
Roaster build forced air and agitator Building a Coffee Roaster 9 10/07/2021 2:30 PM
Larry Cotton's 'wobble disc' heat gun build Heat Gun Roasting 12 09/24/2021 9:16 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