Anet A8 LoadCell BedLeveling

Why?

No Z Sensor offset, just probe with the tip of your nozzle.

how it's looks

Limitation

HX711

In default, the hx711 is set to send only 10 sps, to upgrade to 80 sps, depends on your module, you need to change an jumper replace an 0 Ohm resistor.

leveling

HX711 has only a sample rate of 80 sps and need some communication time, related to this, my bed probing runs with an Z speed of only 1ms/s

G28 XY; home XY axes
G28 Z; home Z FAST
M203 Z1.00 ;slow speed for z for homing and leveling (slow probe)
G28 Z; home Z SLOW
G29 P2
M203 Z8.00 ; reset Z Speed limit

Good to Know

3d model

The 3D model is maybe not the best one yet, the sledge is depends on the LoadCell now wider than usual, this means you need also tweak a little bit your marlin settings for offset of X,Y.

I can't provide my ones, related I have some other tweak from the stock Anet A8 behavior.

arduino source code

In the sourcecode I have currently set static to trigger at an LoadCell Value over 20, if your setup variates, you need maybe tweak this line

  if (i<-20) {

trigger

In the source code, I also set the onboard LED, so you can check visual if your LoadCell reach the force.

what you need

1. LoadCell (I have just take a 5kg one) (~2€)
2. HX711 LoadCell Amplifier (sometimes already in the Loadcell included)
3. Arduino (i have take just an arduino nano clone ~4€)
4. printed 3d models from the (./models) directory (~2€)
5. some wires

cost: around 8€

How to wire

ANet Z Input (5V)     <--> arduino VCC
ANet Z Input (GND)    <--> arduino GND
ANet Z Input (SIGNAL) <--> arduino PIN 4

HX711 (GND) <--> arduino GNX
HX711 (VCC) <--> arduino VCC
HX711 (DT)  <--> arduino PIN 3
HX711 (SCK) <--> arduino PIN 2