Hack eveerything!

  • This is a long one but a good one!

  • Classroom

    I want to hack this coffee grinder together with a scale so that it turns itself off when it has ground the correct amount of coffee. I also want to remove the receiving container it comes with, and make it so my Aeropress fits in that space (and sits on the scale hacked into the system).

    I also want to hack this kettle to have a programmable temperature control.

    Then, I want to hack them together so I can start them from my phone (top video is a big help there).

    I only want to use these models because it is what I have sitting on my counter. I know I could go out and buy a kettle that does what I want (that is less fun though). I haven’t seen a coffee grinder that works based on the mass of coffee ground, and I’m not sure why. Even the $700 grinders I’ve looked at just work on the grind time, but you still have to calibrate the time based on the grind setting used, and change it every time. Sure there are hundreds of places to save presets, but that is a hell of a lot of work to get dialled in, and how many are you really going to use on a regular basis?

    It seems way easier just to specify “18 g @ medium-fine”, and let the instrument figure it out.

  • @kile one of my buddies has a coffee grinder with the built-in scale function. I suspect that you have not seen it because you shop for coffee making gear using different suppliers than the guy who used to manage the kitchen at Red Beard…

    When I AeroPress, I usually weigh out a dose of beans, load it into a small hand-cranked ceramic burr grinder I picked up off Ebay for about $10, then I use my cordless drill to crank it until it has ground all the beans, and dump it into the press. It is quick and does not leave beans in the grinder to go stale.

    That said, I’m playing with load cells and amplifiers for a project I’m working on (I think it would be cool if the machine rolls toward you when you pull the handle, and away when you push on it…), so I can grab parts for this while I’m sourcing my parts. Essentially the same deal, except that you want to use load cells in the 0-50g range instead of the 0-20kg range :)

    Cut the lines that go to the motor, wire to a relay, wemos or raspi controls relay. Add some buttons to adjust settings, wire in the load cell… Easy. If you want to do a timer function, let the microcontroller do the timer. You could even just have a k-type thermocouple and another relay with a 110v socket come off the controller, plug the kettle into the socket, and the grinder can control the kettle.

  • Classroom

    @pierre, my search was neither broad, nor deep. Just far enough to see this wasn’t a common feature, even at the high end of consumer products. I did not look into any industry suppliers.

    I don’t need this thing to work all day every day, just a couple times a day, so what you are describing definitely seems to fit the bill for the cost factor compared to going with something fancy and industrial for this totally-unnecessary, luxury, convenience-item.

    If you don’t mind grabbing a cost for a couple of the load cells while you are sourcing yours, I will probably tack some on to your order. 0-50g fits the bill here, but I’d be interested in what is available at higher and lower ranges as well.

    An analytical balance for chemistry is quite expensive. I think it is just a load cell, some shit to calibrate the input and display the results, and a box with some sliding doors because any movement in the air is enough to throw off the low weight load cell. I would really like to build one of these for myself, and maybe one for the bus and the space as well if they are that cheap.

    There is the possibility to do some cool stuff with glaze mixing too and hack together a neat looking unit for the kiln room. It would be fun to house some of the electronics in mud.

    A load cell, an Arduino, a couple seven segment displays, and some RGBLEDs, and you have a fun blinky contraption to show off how awesome electronics are, and suggest a donation for every object that gets printed on the Prussa.

    How about making a grip-strength testing arcade box from plywood, sheet metal, and simple electronics components?

    So many possibilities…

    I think it would be worth having a few of these around if the costs aren’t overly prohibitive for some decently accurate, fairly reliable, and moderately precise hardware.

  • @kile I always got by with a beam balance setup… Never managed to blow any fingers off with it.

    I have a cheap-o reloading scale now, sometimes use it to measure doses of medication for the ferrets and the like. (If 10mg is good for a 200lb person, how much should a 1.5lb ferret take? Answer: Not very much, and slight spillage is much more significant…)

    An automated version of that scale would be pretty neat… Little conveyor, roll your handloads across it one at a time, and it rejects the one where you accidentally double-charged the powder, or forgot to put power in it. (both very dangerous situations…)

  • Classroom

    @pierre, are the load sensors in the ballpark of a decent triple beam these days?

    If you find one used they can be gotten cheap, but a new one is quite a bit more than they were 20 years ago before precision digital balances became the norm.

    An inexpensive way to handle precise dosing is by dissolving a known amount of a substance, in a known amount of water (or another edible solvent, carrier oil, etc.). It is much easier to weigh out 0.8 mL of water for example than 125 μg of some ferret drugs.

  • Always interesting mashing old things with new technology.

  • @kile More ideas for you!

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