X-axis limiter based on two sub miniature leaf spring switches to sense when the spindle has reached the edge of the x-axis. This leaves only a couple of millimeters to the edge of the x-axis on either side. The switches are mounted to the frame with the original M5x16 screws and can thus be fitted with no manipulation of the frame.
This design consists of two files; x-axis-limit-switch-left and x-axis-limit-switch-right. These pieces are near identical but the right switch has a 2mm longer extrusion to accompany for the stepper motor screws.
The limit switch holder is designed around a sub miniature leaf spring switch with dimensions of approx. 6.5 x 12.8 x 5.8mm. Example model that should fit this design: CYT1073.
Any pair of low power cables should suffice for this application. I do however recommend using a maximum cable dimension of 1.5mm2 to make it easier to solder them onto the micro switch contacts.
The original Genmitsu 3018-PRO control board has a standard dupont pinout for the limit switch connectors and it is therefore recommended to use a dupont crimping tool and 2-pin female connectors to connect the switches to the control board.
Print both 'x-axis-limit-switch-left' and 'x-axis-limit-switch-right' with your choice of printer and filament.
I have successfully printed the design with PLA and with the following settings:
- Extruder Temperature: 230c
- Platform Temperature: 50c
- Layer Height: 0.18mm
- First Layer Height: 0.22mm
- Infill: 15%
- Raft: No
- Supports: No
Due to printing without supports there may be some stringing in the screw holes but this can be easily scraped out with a knife.
Solder the cables to the C (Common) and NO (Normally Open) pins of the switch. I recommend to place a small piece of shrink tubing over the solder joints to avoid shortint the pins.
Fit the cables and switches through the hole of the 3D-printed holders making sure the switch leaf spring is pointing downwards. The switch should snap into place and be helt snuggly by friction. If the switch is loose, apply some superglue to the switch before fitting it in the socket.
Unscrew the middle two bolts holding the bottom guide rail and frame and mount the 3D-printed holders with the switches pointing inwards with the original M5x16mm bolts.
The micro switch model used for illustration is created by Igor Lirtsman over at GRABCAD
