Because of a lack of space, I had to mount the controller to the wall rather than to the y rail. Does anyone see any issues that might arise? Two things I thought of were grounding and heat dissipation. I don’t think there would be a need to run a separate ground wire from the box to the rest of the machine. But heat needs to be asked about. Normally, when the box is mounted to the rail, there is a lot of metal available to dissipate the heat from the board. Mounting the board/box to the wall means there is a lot less metal in contact for heat handling. I have some small 12-volt fans available from an old SPARC box I cannibalized and wonder if I might need to give it some help getting rid of the heat. Or maybe I’m just worried because I have nothing better to do than worry.
I’d be worried. As you say, it doesn’t have the big heat sync of the AL rail it usually does - I’d actively cool it for sure.
You could ground it with a simple wire to one of the extrusion screws as well.
If anything, I’d think that (the above precautions taken) mounting it away from the router and mechanicals would be a Good thing.
I’ve had my controller mounted to the outside of my enclosure for over a year. I seldom shut it off, and I have had no heat related issues. I do not run a fan. So apparently a big slab of MDF is a decent heatsink or my board just does not get very warm.
When you say you seldom shut it off - do you leave the steppers in Hold all the time? Or pass grbl the sleep command?
I just leave it turned on. I’m sure I’m shortening some lifespan. But I just never remember to shut the controller off.