Macrobench #2 (Rev0)
This bench is destined for vertical stacks - actually I just couldn't afford a Nikon Multiphot stand.
Two 20mm steel shafts are mounted in a Beech Butcher's Block base. The steel rods are actually sitting in holes bored in some Australian hardwood rebated into the beech. Just because I felt like it I inlaid a smile into the front of the base.
The base has a couple of kilograms of Tungsten inlaid into the bottom (machine tool blanks I got cheap).
Motion comes from a Parker Daedal LN stage driven by a stepper motor through a 30:1 planetary reduction gear. The gear head doesn't improve absolute positioning accuracy but does enable small moves with no need for mictostepping and gives a high holding power. I initially had the motor at the top of the stack but once I started fitting a camera and subject stage realised it was much better with the motor at the bottom.
The subject will be held on a 3 axis micrometer driven stage.
Lights are held on swinging arms clamped to the steel shafts.
The setup really needs limit switches for the motion but with the gear head it is so slow nothing is going to crash at high speed.
At some time in the future I will add a linear encoder for absolute positioning but it is not a priority.