@aparrish The chainsaw will not sustain any damage, although you may want to give though to what surface you clamp the keyboard to - a wood bench perhaps, try to avoid metal. The keyboard will likely launch keycaps, and depending on age, metal keyclips, springs, plastic buckers as debris. A modern cheap keyboard with membrane keyswitches will pose no obstacle: an old Model M with a steel backplate should be avoided for obvious reasons, but you've covered that angle. Good luck!
@aparrish Ah, gotcha. I'm willing to bet rental chainsaws have been through *far, far worse* than even the most horrific of keyboards. XD