Limit Switch to stop stepper motor

Forum dedicated to discussion and technical support centered around the LittleRP affordable, open source 3D resin printer.
alitans
Posts: 1
Joined: Mon Oct 10, 2016 7:38 am

Limit Switch to stop stepper motor

Postby alitans » Mon Dec 11, 2017 5:45 pm

Hi Guys,
I am planning to install a limit switch to little rp 1 as stepper motor has no button to stop and it sometimes pushes the VAT floor very tight. Can any 1 guide me how to wire the limit switch with the PCB?

goopyplastic
Posts: 236
Joined: Sat Mar 29, 2014 6:16 pm

Re: Limit Switch to stop stepper motor

Postby goopyplastic » Thu Jan 18, 2018 8:00 pm

There is a Z limit footprint on the shield, you can solder the wires directly do it, or solder in a connector. The switch should be wired for normally open. How the LittleRP2 limit switch is designed it to home at the top of the printer, then use a g code command of a known distance to bring the arm down to z. I think this is a better approach then trying to adjust a z min position.

I also tend to lower the arm all the way then fine tune the z height manually by twisting the motor threading with my hands and watching the build plate through the mirror.