The location of the Z endstop

Hi every one.

I have a small question about z-endstops.

I know where to put my endstops for X and Y, but I do not know where to place Z. For me, it would be logical to place it at max (that's when my bed is completely down), but when I look online at other builds, I can see that they have placed them at minimum (ie when the bed is completely up and close to the extruder). However, I can not see how this can be done without the endstop getting in the way of autoleveling and the first couple of layers.

Will the Z endstop not be pressed down every time the bed moves up to the extruder, and is there not a risk that the endstop will be compressed excessively?

Here are three options:

1. Z endstop at Z max. This is a popular choice. If your Z axis is slow, this can slow down things a little, because of the need to move from Z=max to near Z=0 at the start of a print.

2. Z endstop at or close to Z min. In this case the endstop arrangement should be designed so that the bed can move a little past the endstop trigger position without damaging the switch; or else you must have solid mechanical endstops to prevent the bed moving significantly past the trigger position.

3. No endstops. Use the Z probe for homing. I've read that Smoothieware doesn't support this, but all other firmwares do AFAIK.

HTH David

Edited 2 time(s). Last edit at 11/27/2017 08:44AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Ahh, of course I can use my z-probe. It's already right there. thank you.