iSpindle - DIY Electronic Hydrometer

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Finished building up one of these over the weekend. I used the Wemos official lipo board and a different accelerometer, but it's basically the same stuff (need to merge the official firmware with my test code). I was excited to find such a long and active thread about it.

Is there anything NOT on HBT?
 
Has this thing evolved to the point where I can buy a kit, build it, load up the software, and just start using it? Or is it still a project to get it working? I don't want to become interested if it's going to be a big project.
 
I just finished building five of these. All of them accepted the firmware nicely and seem to work, as they seem to report tilt and temperature fine. I just need to calibrate them and try one out with my next brew.

I got the XL petlings with a 33mm ID, and used this sled -> https://www.thingiverse.com/thing:2169567. Not sure if I need to add weights for the proper tilt.
 

Attachments

  • ispindel_1.jpg
    ispindel_1.jpg
    2.8 MB · Views: 570
  • ispindel_2.jpg
    ispindel_2.jpg
    2.3 MB · Views: 562
  • ispindel_3.jpg
    ispindel_3.jpg
    2.6 MB · Views: 538
I just finished building five of these. All of them accepted the firmware nicely and seem to work, as they seem to report tilt and temperature fine. I just need to calibrate them and try one out with my next brew.

I got the XL petlings with a 33mm ID, and used this sled -> https://www.thingiverse.com/thing:2169567. Not sure if I need to add weights for the proper tilt.

Youll probably need about 11gs at the bottom of the sled on the opposite side of the battery. You’re aiming for a 25degree tilt in water.
 
Youll probably need about 11gs at the bottom of the sled on the opposite side of the battery. You’re aiming for a 25degree tilt in water.

Thanks for the heads-up. That reinforces my hunch. Guess I need to go hunt for some tire weights or slap a couple of nuts on there with hot glue.
 
The iSpindel reports the tilt itself on the info page after it has been calibrated on a level surface first.. unless I missed something?

no that's right, getting it into setup mode and connect to it via a computer (as they're easier to keep awake than a mobile phone), then select info and it gives you real time tilt.

I used a 10g tyre balancing weight vertical right at the bottom of the sled and a 5p coin glued above it. it was around 11.5 gs but the spread of weight is equally as important, as an example.

a 20g weight placed at the bottom when shifted from horizontal to vertical changed the angle about 10 degrees, I'm sure there must be a smart way to work out the right amount of weight and approximate centre of gravity, but I just went for trial and error.
 
Last edited:
Dear All,

I know a few of us have had some trouble with the iSpindel going into deep sleep and not waking at the prescribed time (say every 15min).
I built several boards with 470 ohms resistors that failed to wake, and only when I used a BAT43 Schottky diode did it work. However, my question is has anyone had any success using a lower resistor of say 390, 350 or 330 ohms?
The reason for this, is I believe that a Schottky diode will still cut out when the battery voltage to say 3.6 volts in comparison to a resistor of the correct value may go down to 2.8 volts.
Therefore, any input would be appreciated?
Thanks.

Also on Github it now says to use a 330 ohms resistor or BAT43 diode?

After enough reading, I share your concern.
I have 330 ohm resistors on hand and can pick up 390 ohm at a local shop, but BAT43 I would have to order in.
I'm about to build five of these and with the charging circuit covering the resistor holes, I'd like to get it right the first time.


EDIT: I also wanted to point out this most excellent sled design.
https://hobbybrauer.de/forum/viewtopic.php?p=262593#p262593
 
EDIT: I also wanted to point out this most excellent sled design.
https://hobbybrauer.de/forum/viewtopic.php?p=262593#p262593

That is genius, thanks for pointing it out. The designer shared the files a couple of posts down, so I loaded them up on Cura, and the size of the base sled is 35,6 x 118,0 mm, so the design is for the bigger petling, for anyone wondering.

I built mine with the BAT43 diodes after reading up on the issues with resistors, but I didn't realize that it will likely cut out at lower voltages.
 
I built mine with the BAT43 diodes after reading up on the issues with resistors, but I didn't realize that it will likely cut out at lower voltages.

I haven't analyzed the power circuitry all that much, but the VDD minimum of the ESP-12F (ESP8266MOD) is 3.0V.
So, even though an NCR18650B for example can go as low as 2.5V, I don't think you'd want to chance running the D1 that low anyway.

For reference, the kit available here moved to a 390 ohm resistor.
 
I just finished building five of these. All of them accepted the firmware nicely and seem to work, as they seem to report tilt and temperature fine. I just need to calibrate them and try one out with my next brew.

I got the XL petlings with a 33mm ID, and used this sled -> https://www.thingiverse.com/thing:2169567. Not sure if I need to add weights for the proper tilt.
How do you charge them?
 
unscrew the lid and then plug in a micro or mini USB cable in the battery lipo charger. i did see someone somewhere has installed a wireless chargin coil into the lid, which will help ensure you don't compromise the balancing of the iSpindel, but yeast has a habit of getting into and around the lid thread.
 
Any idea why mine is updating once after a reboot, but doesnt update at all after that? Time is set to 900 seconds and it doesnt update every 15minutes like it should... Im using the BAT43 diode.
 
Hi, I'm looking for help in getting my iSpindle working. Is this a good place to ask?
 
Thanks. The story so far: I built my iSpindle and it didn't work. I resoldered the joints and that helped. I managed to get to the point where I was running the software and able to communicate with it over wireless. At that point it was working but it didn't seem able to power itself by battery. The battery charged but once the USB was unplugged it did nothing at all. Whist on USB it was sending to Ubidots happily but nothing when unplugged.

After messing some more I'm now at the point where not much works and I can't even get a serial console connection to the wemos.

If I plug in the USB for power the charging board lights up. Using the switch I can turn the wemos on and the blue light on the wemos either flashes or goes solid blue, at random. Pressing the reset button quickly makes the blue light flash. Pressing it for a little longer generally means the blue light goes solid. At no point does the console seem to register. I've tried it on Linux where dmesg is generally good at logging USB activity and there is nothing.

I've tried resoldering the pins again without success. I don't know what I may have done, how to fix it or how to check what's going on. I don't even know what the lights are indicating. Documentation seems a little sparse and there doesn't appear to be an official help forum/mailing list/BBS etc.

I've placed an order for another wemos and MCU so at least I can maybe isolate whether the problem is the wemos side or the power side. Anything you can offer in terms of help would be appreciated.
 
Is there a current/valid schematic for this project that one can obtain?
On the typical hobby project if a battery will charge but will not power the board on its own there is a diode either backwards or placed where it shouldn't be...

Cheers!
 
Is there a current/valid schematic for this project that one can obtain?
On the typical hobby project if a battery will charge but will not power the board on its own there is a diode either backwards or placed where it shouldn't be...

Cheers!

@day_trippr , while probably not up to your professional standard, here is the schematic @Mikmonken and I created to produce the WeMos shield @Nevryn purchased from 3D Mechatronics.

I just followed the documentation at:

https://github.com/universam1/iSpindel/blob/master/docs/iSpindelbreadboard_en.md

The only diodes I'm aware of were the two LEDs it says to remove.

(The breadboard wasn't like the one in the docs but a custom PCB. I got the kit through 3d mechatronics.)

If the kit is providing the recommended diode rather than the 470 ohm (R3) resistor, that could be the problem. Pictures might help. Also, as a side note, I recommend not removing the LED on the gyro. It shows that its powered up and my battery life is more than adequate with it left in place. (using a 5 minute reporting interval)

ETA: It looks like 3D Mechatronics provides a 390 ohm resistor for R3
 

Attachments

  • iSpindel_Schem.pdf
    33.3 KB · Views: 199
IMG_0856.JPG
IMG_0855.JPG


Hope these help.

I've got a new Wemos and Accelerometer so I'll put those together without removing LEDs initially and see how it goes.
 
In the US what's a source for materials? PET preform and sled? (Or are they called drawers?)

If I knew what preform to get and which sled worked for it I could just have my local library print up a couple sleds for me.

(edit)
I'm guessing this is what I want? https://www.ebay.com/itm/5-XL-BIG-P...354446?hash=item1ed26ca54e:g:0LkAAOSwe-FU4GqL

Or no because all of the listed dimensions for the sleds on the iSpindel website are larger than the inner dimensions of this xl preform...
 
Last edited:
@Nevryn , are you plugging the usb into the battery charging board or the Wemos? The battery could be dead if you are plugging it into the wemos, since I don't believe the battery will charge. The only time you connect to the Wemos USB is during programming. And the battery should be fully charged during programing.

If you press the reset button and the Wemos LED blinks slowly, you are in access mode and should be able to connect to it over wifi.

While the soldering doesn't look great (This could be from multiple attempts), I don't see any major problems. The Wemos D4 pin and the 5v Temp Sensor pin on the shield don't look like they have good joints, but D4 is not connected to anything on the shield.

Do you have a multi-meter by any chance?
 
In the US what's a source for materials? PET preform and sled? (Or are they called drawers?)

If I knew what preform to get and which sled worked for it I could just have my local library print up a couple sleds for me.

(edit)
I'm guessing this is what I want: https://www.ebay.com/itm/5-XL-BIG-P...354446?hash=item1ed26ca54e:g:0LkAAOSwe-FU4GqL


That is the XL PETling. I ordered the XXL PETling from the same vendor and it fit the sled perfectly.

XXL PETling: 5 pcs XXL set of BIG PET Micro Geocaching container geocache preform Soda bottle

Sled: iSpindel Sled
 
ISpindel and node-red

From versiom 5.4.2, iSpindel is able to output through a TCP protocol. Node-red https://nodered.org/ is an awesome open source plataform for the IOT world and I created a Dashboard for monitoring iSpindel localhost (But it works with node-red hosted anywhere on the internet). From node-red you can route your data to any other service or databases.

To use the code just copy the JSON and import to your node-red installation:

https://flows.nodered.org/flow/56631ba320500464003778b638baf445

There are nodes for sqlite, influxdb and mysql for instance and I have just realized there is a new node for quick connection to ubidots https://flows.nodered.org/node/ubidots-nodered.

Please report any problem or success with the code/usage

Hope you enjoy! Cheers
 
@Nevryn , are you plugging the usb into the battery charging board or the Wemos? The battery could be dead if you are plugging it into the wemos, since I don't believe the battery will charge. The only time you connect to the Wemos USB is during programming. And the battery should be fully charged during programing.

Generally I plug both in and I've left the charger plugged in overnight so the battery should be charged, although I don't know how to be certain of this.

If you press the reset button and the Wemos LED blinks slowly, you are in access mode and should be able to connect to it over wifi.

Currently I can't get a console connection through which to flash the memos again, let alone get the firmware to boot to the point where I can see the SSID.

While the soldering doesn't look great (This could be from multiple attempts), I don't see any major problems. The Wemos D4 pin and the 5v Temp Sensor pin on the shield don't look like they have good joints, but D4 is not connected to anything on the shield.

Do you have a multi-meter by any chance?

Yes, I've resoldered a couple of times to try to eliminate any dry joints and to reposition the pins to try to make a better connection.

I have a multi-meter, yes.

Thanks for help.
 
Try using the multimeter to see if you get the necessary voltage at the Wemos with the battery turned on and not plugged into any USB. It does sound like a power issue to me.
 
Thanks. Will do. Could you clarify which pins I should be checking and what voltage I should expect from a charged battery?
 
Back
Top