I’m making inexpensive microtomes to use with the foldscopes.
Here are the items I used.
You can use either an empty wooden or plastic thread spool. In order to have a surface on which to glue the nut and to have a firm cutting surface, glue a metal washer on each end of the plastic spool. The wooden spool didn’t seem to need one.
I used 1/4-20 x 2 inch flat Phillips bolts with nuts which fit into the spools nicely. Glue the nut to the end of the spool using a hot glue gun or other waterproof glue.
Then glue a small wooden craft stick to the end of the bolt to use to turn it.
You can mark increments on the spool with a waterproof marking pen for uniform samples. Two strips of carrot can be used to hold the specimen in the microtome.
Single-side razor blades are used to cut the section. Dip the blade and section into a bowl of water and the section should float off.
Have fun! Post pictures.