DIY Data Logging Scale with Android App (w/source)

[@TilmanBaumann]

This is wonderful. I'm building something similar right now. Achieving slick hardware is such a challenge...

[@jshet]

I love your videos. Great tempo. Enough content. Thank you.

[@kwakeham]

Very neat work making it compact. Love it when people reuse enclosures to hide improvements. For significantly increased accuracy (like several orders of magnitude and way increased stability) ditching the hx711 and moving to even the ads 1220 breakouts will increase stability a lot. These hx711 are cheap and common and can get jobs done when accuracy isn't paramount.

[@TechDregs]

Yeah, the HX711 I already had, and I'm really only looking for 0.1g resolution. I looked into some of the other ADCs, and for precision work, a person could do a lot better.

[@gabrielcr78]

Outstanding!!

[@mkupkatx]

Happy Lent!! I noticed the RCBS scale on your workbench. Have you considered making an automated precision powder dropper for a progressive press?

[@TechDregs]

No, the nature of a progressive would make that very difficult. I use an Autotrickler v4 for my loads these days, and it's fast enough for the style of shooting I do. For high volume shooting, the volumetric powder measures on the progressive stuff is usually adequate, but for someone doing accuracy competition, they'd probably need to verify every load anyway.

[@terrymiller111]

I am your 438th subscriber. I have a good feeling about your future.

[@stephanc7192]

Great video Looks like you do some reloading as well. 😉😎

[@ivanbilic5391]

only thing left to do is to make it so that can replace grinder scale (maybe via usb or bluetooth), so that you can use same scale for both 😉😉

[@stefanguiton]

Excellent video

[@JeremyCook]

Ha, that OLED modification was a bit triggering! 😄 Nicely done. I thought the XIAO had built-in battery management?

[@TechDregs]

It does, but the ESP32-C3 version seems to lack a voltage monitoring pin. So, it'll handle the charge and everything, but you can't read it out internally. I think the Nordic version has internal pins for voltage that can be used. It costs twice as much, but it's probably even better for this design, as it's more power efficient.

[@JeremyCook]

@@TechDregs Ah, that makes sense - kind of what I thought after I considered it a bit more. Was initially a little disappointed, as I saw your last video and was kind of excited about the battery management of the XIAO... Not that I need another dev board.

[@gino_latino]

What about a Zigbee firmware or Tasmota? BLE with Open Source firmware is good, but joining a standard is better

[@TechDregs]

Those seem to be more focused on IOT devices. I really intended for this to be more of an active tool to collect data, rather than something to connect to a network or to be controlled remotely.

[@Jimunu]

Good video.

[@revvrav]

Does this calibrate the load cell, i'd like to use a different one with higher weight?

[@TechDregs]

Should work for higher values. There are calibrations you can do, if you dig into the underlying libraries for the HX711.

[@revvrav]

@@TechDregs Gotcha, thanks for your reply!

[@PeterCooper-u4z]

Is it possible to disable the auto-off function of the display?

[@TechDregs]

The logging scale doesn't auto-off; it's just controlled by the power button. For the Android side, you can use a stay awake routine. I think there is a setting to keep the screen active in the GUI also. Been a while since I used it though, so I'm fuzzy on those details.

[@PeterCooper-u4z]

That's actually brilliant, I've been looking for ages for a weight logger which can work in a sealed box - will give this a try, thanks @@TechDregs

[@TechDregs]

One modification you might add that I didn't is powering the HX711 via a GPIO pin that you can turn on/off at wake/sleep. That will keep it from drawing power when the unit is in deep sleep (it's a soft power button). That will massively increase battery life when it's powered down. You could also bump the resistors for the battery monitor pin up to 500k or 1m to draw a little less current... but that will have a far smaller impact on battery life.

[@lachlanlau]

4:42 that's an OLED..

[@TechDregs]

Yeah, I call it both during the video... just didn't feel like editing it back out. LOL.

[@lachlanlau]

@@TechDregs laziness (TM)

[@FranzDebussy]

Catholic bros lets go