A microtome is a machine which cuts (usu.) biological specimens into very thin sections. The sections are typically mounted on microscope-slides.
This was an idea I had, I did it, and I've demonstrated it with garlic
It creates slices 250 microns thick*
If anyone is actually thinking of building one of these see the last step. You can also PM me if you need more
Step 1: Construction: Base and Mount Runners
These images show the base of the device and the red runners for the specimen platform, also the final drive to the rack.
Step 2: Construction: Mount Plate
Being Lego, the plate can be easily customised to hold a variety of samples.
Step 3: Construction: Upwards Towards the Gear-train
In this sequence you see the front rails that hold the blade assembly being added (yellow and grey)
Step 4: Construction: Gear-train
Step 5: The Blade
Step 6: Construction: Finishing
All the way to the end:
Step 7: Additional
The gear-train to the blade cranks is a bit too long: all the gears make it a bit loose. It would work better with lever connections.
The blade assembly (grey) needed glue - it picked-off afterwards, but it's not strong enough without.
As you can see from the video it does work, but I needed to be a bit careful.
Your main considerations are:
A good solid platform that is fairly tight
Similarly for the blade
A lot of reduction from the crank. I work out 3 x 5:1 giving 125:1
Disposable razors tend to be held together with little plastic rivets. You can find these as round blobs on the underside - cut these off with a sharp knife and carefully prise the thing apart with the knife. These blades are very sharp and you'll tend to see blood before you feel anything.
To glue it on - I put the blade and Lego on a sheet of cling-film stretched over a tile, and carefully dribbled 2-part epoxy down the edge.