This method is pretty cool @mrehorstdmd. I also used it like that for a long time, but I'm building a voron and I wanted to leave a small camera inside the machine, more for aesthetic reasons. I used a cell phone for a long time and then switched to a xiaomi ip camera, to look at 2 printers when I was away from home. Thanks for your response!
@cncmodeller It would be easy to modify a bluetooth button with a reed switch in parallel with or in place of the pushbutton and then place a small magnet on the edge of the printer's bed. Every time the bed rotates with the magnet near the switch it will trigger a photo. I don't know how precise it would be, but with a little more effort you could use an opto interruptor instead of a reed switch. They can be very precise, so your resulting video would be very stable.
Which pins would you like to use? One of the heater pins on the expansion port would be a good choice.
What kind of signal does your LED mosfet require?
How you configure it would depend on which firmware version you are using. In RRF3 it's as easy as defining the desired pin with a M950 command as a fan, and then using a M106 command to control that fan output.
@t0bias, if the board is detected then the I2C pins are connected correctly and the slave address is set correctly.
How are you testing the outputs of the SX1509B? I have connected each output through a 100 ohm resistor to one of the cathodes of a 2-digit common anode 7-segment display, with the anodes connected to +3.3V.
Here is actually using 3 sensors, in 45degrees steps. The auto compensation software may also need to know the filament length between each of the three sensors and the extruder and merge length shifted values to construct an estimation of the cross cut.
Considering the common tolerances of modern filament, I wonder if this complexity will result in a significant part improvement.
A simple way to test is to print 3 models with -2%, 0% and +2% from your current setting and see if the differences are significant.
Edit: regarding how useful it is, his magnetic strength based design is clever and cool.
I have two Brand new Duets still in the box and as soon as I have the machine ready I will give it a try, however I am looking at an uphill struggle. My forte is mechanical Engineering and I would need to scratch deep to find what I need to do, however this site has a goldmine of information and I will try to manage.....
@oliof well for starters "me not making it work" does not in any stretch of imagination means "no one can make it work" 😄 😄 😄 😄 ... but I have my reservations about repeatability and precision as for e.g. in theory piezo disks should be the perfect endstops and should be way more precise and more repeatable than anything else out there but I know ppl that are finally happy with their printers after moving away from piezo... same here, I don't think it's solving "a problem", there's enough great sensors out there today, adding a new way to detect boundaries is not bad thing but hardly something that we need. with all the fancy stuff we did in 12 years of reprap project I don't see a significant increase of precision over simple, cheap, microswitch 😞
I aggre with ther thermal cutout. I was thinking of a bi-thermal clickson that needs to be fisicaly reset if max temp is exceeded what is the highest temp one would have too hit with a heated bed,, what max should i shoot for ??