IMO limit switches for the Blidgeport - mechanics

Limit switches - the need:

Now that the table is moving about in X and Y, I need to fit some limit switches before I manage to run it into the ends of travel and break something. The servos are only 400W (1/2 HP) but with up to 3000rpm and peak torque of something like 5Nm combined with 2.5:1 stepdown, there's enough torque available to bugger something up.

IMO LR series switches:

The limit switches are just to stop movement beyond the software-defined extents. So they don't need to be precision limit switches. However, it's worth getting something that vaguely resembles industrial quality. You can spend what you want on these but I found some IMO ones at a half decent price at CPC (aka Farnell). Limit Switch, Roller Lever, 1NO / 1NC, 6A, 250Vac - LRC5A31 

These are of a configurable / modular design ie you can specify a wide range of actuation options, switch configurations, mounting positions, cable entries etc. They also claim to be IP67 or so, which seems sensible for this application. Link here to the datasheet. In my case, I've got a roller arm, a pair of NC and NO contacts (snap action) and an M20 x 1.5mm threaded inlet to take a standard cable gland. You can fit the roller arm at various angles and offsets. 

The switch module lifts out once you remove the cover, which makes wiring simpler:

Std cable gland fitted:

Let's not fuck about here. Here's the Y axis +ve limit switch ("Y L+") mounted at the end of saddle travel:

And the Y axis -ve limit switch ("Y L-"), actuated by the rear face of the saddle. Mounted but not wired up yet. 

This is how I plan to mount the X axis limit switches:

Boom. There you go - X axis -ve limit switch ("X L-"):

All 4 table limit switches mounted:

As for the X limit switches, these spring plunger blocks came with the Align power feed which I have now removed from the X axis. I'll be refitting it to the knee later but these blocks won't be much use there anyway and they are a convenient shape to work with my limit switches.

There. Just need to connect them up now, as they aren't wireless ones ;-)