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snwcmpr
10/18/2019 2:37 PM
Eth Nat Yirg Idido roasted yesterday. I dropped some off at a friends coffee shop. In a few days he will brew it and tell me what he thinks. We believe my roasts are better than what we buy.

snwcmpr
10/16/2019 2:52 PM
Thank you for all you guys do.

JackH
10/15/2019 2:02 AM
They seem to be after the shoutbox. They have been removed. I don't see anything in the forums.

snwcmpr
10/14/2019 3:27 PM
We have been hacked. A whole lot of posts that have filled up the whole forum.

snwcmpr
10/10/2019 4:49 AM
Honduras Royal Reserve today.

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Fluidbed roaster build... questions...
renatoa
So bad that today sink drain are made of plastic, with only the top perforated cover made from stainless... :( Here is a challenge to find such metal drain sets.
 
Brewin_Bruin
elkayem wrote:
elkayem wrote: "I don't have any firm evidence on why the original setup didn't work, but my suspicion is that the corrugated hose that came with the the air pump was slowing down some of the air flow. "


Yes, you are quite correct, corrugated hose is well known for slowing down airflow. You can find a lot on this topic in discussions of dust collection issues for woodworking shops.

One alternative for controlling/reducing airflow that IS cheap and simple came to mind. It's been mentioned by others in the fluidized bed forum: instead of controlling the motor speed you can introduce a variable leak via a Y or T connection between the blower and the heating coil, with a valve that allows you fine control. Since most of the current is going to the heater, you can sacrifice a little electrical efficiency for simplicity and lower equipment cost. Following the "KISS" principle is generally a good design perspective. It might whistle, depending on how things are configured.
Edited by JackH on 05/29/2018 8:47 PM
 
elkayem
CharcoalRoaster, thank you for the pictures! I'm trying to discern how you connect the funnel to the heat tube. It looks like some kind of a rubber tube enclosed in a metal tube with a clamp? Looks clever.

Garageroaster, nice design! I was thinking of some kind of a threaded interface like I see in your photo, but couldn't figure out how to spin the RC with the thermocouple wires. I'll have to check out the Ace hardware kit you mentioned. Also, yours must be the only one with a roast chamber supported on the back of a turtle.
 
elkayem
Brewin_Bruin wrote:

One alternative for controlling/reducing airflow that IS cheap and simple came to mind. It's been mentioned by others in the fluidized bed forum: instead of controlling the motor speed you can introduce a variable leak via a Y or T connection between the blower and the heating coil, with a valve that allows you fine control. Since most of the current is going to the heater, you can sacrifice a little electrical efficiency for simplicity and lower equipment cost. Following the "KISS" principle is generally a good design perspective. It might whistle, depending on how things are configured.


This is a very good idea. I already have a PWM controller I am using with my smaller roaster which I intend to reuse, otherwise I would certainly implement it this way. I agree that this is simpler.
 
Brewin_Bruin
elkayem wrote: " I already have a PWM controller I am using with my smaller roaster which I intend to reuse, otherwise I would certainly implement it this way."

Be careful with PWM and AC motors, unless you do extra tricks like zero crossing, they don't play nicely together, but with DC motors, it's fine.
 
elkayem
Brewin_Bruin wrote:
Be careful with PWM and AC motors, unless you do extra tricks like zero crossing, they don't play nicely together, but with DC motors, it's fine.


Not to worry, I have selected a 12V DC motor.
 
garageroaster
elkayem wrote:

CharcoalRoaster, thank you for the pictures! I'm trying to discern how you connect the funnel to the heat tube. It looks like some kind of a rubber tube enclosed in a metal tube with a clamp? Looks clever.

Garageroaster, nice design! I was thinking of some kind of a threaded interface like I see in your photo, but couldn't figure out how to spin the RC with the thermocouple wires. I'll have to check out the Ace hardware kit you mentioned. Also, yours must be the only one with a roast chamber supported on the back of a turtle.


Yes the fore mentioned are the two issues I have moving forward. Right now I'm not using probes but will when I get time to work that all out. Eventually I'll build a box with a recirc line and probably secure the RC down then just vacuum out the beans. Then I can have all the wires I want.
 
elkayem
It's been a while since I posted to this thread, so I thought I would take a moment to post an update. My build has been proceeding very slowly, but I'm in the home stretch now. A friend gave me access to his laser cutter, which led to a very nice case. The 12V "Air Pig" pump has more than enough power. I'm getting great bean circulation. Perhaps I'll post a video soon, when I start roasting. The only thing left to add is the heating element. Perhaps I'll make a final push to complete this project, and get it all together this weekend.

Here is a photo:
elkayem attached the following image:
img_2013.jpg

Edited by elkayem on 08/18/2018 9:26 AM
 
blumes
elkayem wrote:

It's been a while since I posted to this thread, so I thought I would take a moment to post an update. My build has been proceeding very slowly, but I'm in the home stretch now. A friend gave me access to his laser cutter, which led to a very nice case. The 12V "Air Pig" pump has more than enough power. I'm getting great bean circulation. Perhaps I'll post a video soon, when I start roasting. The only thing left to add is the heating element. Perhaps I'll make a final push to complete this project, and get it all together this weekend.

Here is a photo:


Supeeeer :-)
 
elkayem
Thanks!!

I finally got everything together and roasted my first half pound this morning. I am enjoying a very tasty cappuccino as I write this post.

For anyone curious about the details on this build (especially the electronics and code), I've just updated my github page here: https://github.co...feeRoaster.
 
allenb
Very nice that first roast in a new roaster build is giving a nice espresso results! You did well in your planning and implementation! BBQ grill
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
renatoa
Congrats !

I can suggest you or others interested into a "next project" to consider the MCP4324 sensor board instead the MAX, is the chip used in TC4, much cheaper, at least same performance class, and 4 channels.

A 4 channels MCP4324 board from eBay cost less than half of a single channel Max31855 board, which also are massive subject of counterfeits, the fact that such boards are sold less than the price of chip itself should raise you an alarm signal.
 
BenKeith
Got off subject so deleted it.
Edited by BenKeith on 08/27/2018 12:22 AM
 
elkayem
Allen and Renatoa, thanks!

renatoa wrote:
I can suggest you or others interested into a "next project" to consider the MCP4324 sensor board instead the MAX, is the chip used in TC4, much cheaper, at least same performance class, and 4 channels.

The MAX31855 is a full-fledged thermocouple to digital converter, including on-chip cold junction compensation. On the other hand, the MCP3424 is just an ADC chip, albeit a very capable one. They are not the same thing.

You are correct that the Adafruit boards I used are expensive, at $15 a pop. For a one-off design, I don't mind spending extra for an authentic part from Adafruit rather than a clone off eBay. I like the company and their mission, and support them when I can. Plus, my code uses their libraries extensively.
 
greencardigan
How do you find the MAX31855 in use? I've been experimenting with them attached to a Raspberry Pi and they dont work with grounded thermocouples. Have you had any issues with that? Is your roast chamber grounded?
 
JitterzZ
garageroaster wrote:

elkayem, my build was based off of OGH's design also but instead of a cocktail shaker I used a sink drain kit and a 7" drain elbow. By doing this I was able to utilize the nut and threads to secure the roast chamber. When my roast is over I vacuum off the chaff and simply unscrew the base to dump out the beans, it actually works pretty good. I'm still in the prototype phase but am going to be building a box to house and stabilize the unit once I get time. The drain kit was $17 at Ace Hardware. Cheers.

NICE! Is that a Bake-A-Round? How is it secured to the sink drain?ThumbsUp
 
elkayem
greencardigan wrote:

How do you find the MAX31855 in use? I've been experimenting with them attached to a Raspberry Pi and they dont work with grounded thermocouples. Have you had any issues with that? Is your roast chamber grounded?


Greencardigan, sorry for the delay! I haven't checked into this forum for a while and see your note was posted nearly 2 months ago!

In any event, yes you are correct that MAX31855 requires an ungrounded theromocouple. If using a grounded theromcouple, I would imagine it would work if your Pi is floating relative to the thermocouple ground. I use an ungrounded configuration, with an exposed thermocouple bead. Kapton tape does wonders for holding the bead in place.
 
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