Mini-Lathe DRO Battery Life

The Mini-Lathe DROs eat a 390 alkaline coin cell a year, more or less:

Mini-Lathe DRO - battery life
Mini-Lathe DRO – battery life

The other DRO’s cell was 10 mV higher, so it might have survived another few weeks. I’ll call it a year, as the OEM cells failed half a year after I got the thing and these are the second set.

The last time I did this, I wedged a thin foam sheet below the display PCB to put a bit more pressure on the (+) contact tab sticking down from the middle of the plate:

Mini-Lathe DRO - battery compartment
Mini-Lathe DRO – battery compartment

The (-) contact is a pad on the PCB below the battery compartment. The glaring metal reflector is part of the curved cell retainer.

I still wish the DROs didn’t collide with the compound slide, but you can get used to anything if you do it long enough.