Well,
i decided to start with the stuff i have at hand now and to make the concessions needed to go on:
- The Power supply will be taken from the GPIO of a CB1 Module, mounted on a Manta M8P Board. I cant offer a better one at the moment.
- I’ll use the noisy Breakout Board as is, since I haven’t seen any alternative suiting for mounting on printheads.
- So I’ll keep the length of the load-cell wiring very short (appx. 5 cm max).
- I’m using a full bridge, of homebrewn load-cells, simply strain gauges glued on a printed plastic part.
- The ADC will get mounted in immediate vicinity of the Hotend, so we get a hard test regarding to environmental influence (heat).
- The whole cabling between printhead and electronic compartment will be done with shielded cabling, including endstop and Fans, all in separate shielded cables - but excluding Heater - maybe thermal measurement becomes shielded together with the endstop.
- I’ll try the circuitry as shown in the above schematics with no filtering.
So loads of concessions here, but my aim is not to get an accuracy of one gram but to get just sufficient readings for endstop functionality.
After all I’m just curious if i get readings at all. If i do, we might have an idea, where the lower limit of functionality is reached - or missed.
Keep your fingers crossed!