Spindle switch box for CNC 20mm section mounting

I've got a cheap Chinese 1610 desktop CNC router, which is really excellent value for money. However, I decided for safety and convenience that I should be able to isolate the spindle motor from the power supply, such as during tool changes and when using the motor power feed with a laser module.

I also wanted the switch away from the motor to make it safer to use if the machine is in use when isolation is needed. That seems quite important as having hands near a working cutter/tool isn't a good idea! So, I came up with this design that can be mounted at the end of one of the 20mm-section frame components.

The model is in two parts as that allows it to print well on my XYZPrinting Jr. 1.0 3D printer. The frame-connector simply fits in the switch box recess, and I used a little bit of superglue to secure them together. Then the bits sticking out of the bottom should slide into the end of a frame section, hopefully with a nice snug fit.

The OpenSCAD file I used is included in case modifications are necessary, or to save time if you need to connect another project to a frame end. I included a snugness ratio variable at the top of the code that can be adjusted, if necessary, to scale the frame inserts if you find then too loose or tight for your frame (the value of 0.95 worked for me though, so hopefully you won't need to change this).

You should be able to use the model with any 20mm-section framed CNC, not just the 1610. Also, it could be useful for other things beside spindle power isolation. And if you're interested you can also read my blog-post about this project at the link below.

https://cncmakerzone.co.uk/adding-a-spindle-motor-switch

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