Last week was a “little lens” frenzy. It started out with a coworker asking me if I had a Leeuwenhoek style microscope that they could borrow for a Museum program. That pushed me to finally give it a try. It turned out that I had all of the materials, so I got started Thursday night at Microscope Makers night. I got the two plates rough cut and hammered to give them a hand worked look. Doesn’t quite look like the Leeuwenhoek microscopes I have seen, but I do like the look.
Then Friday evening I worked on the main positioning screw. I was working with some rod that was a little large in diameter so I machined it down a little. Then used a die to thread it. The closest one I had on hand was 6-32. I filed the end instead of hammering it flat.
I liked the look. I didn’t want to mess it up, and timing was going to be tight with needing it for the Museum program so I went with the filing.
Saturday was the big work day. I had some bead lenses that I had made a few years back, but they were not as round and larger as I was hoping for do I got out the torch.
It was a little tricky taking the photos and working the glass so the photos are not the best…
Then shaping the brass plates. I super glued them together for the cutting, filing and drilling, then a little heat on the stove popped them apart:
There is a 1/8 inch diameter ball bearing that I used to make the dimple in the brass. Bearing in the middle, sandwiched between the brass plates at the drilled lens hole, and that between two fir blocks, end grain towards the brass. This was then smacked with a hammer about 4 times.
I sanded the inner surface of the brass plates to take off some of the larger bumps from the hammering.
Next was the bracket, focusing screw, attachment screw and specimen mounting pieces.
Then hammering the rivets. For this and the initial hammering of the flat metal I used a cleaned up piece of leaf spring as an anvil. The leaf spring was found by the side of the road on a hike earlier this year.
Taping all the holes, and putting the parts together, here is what I have, finished that Saturday evening.
I tested it out with a few strands of feather. The focal length is pretty short! I’ll check the magnification soon.
I did use a few websites for guidance. For measurements and general construction I used Alan Shinn’s piece:
For making the lens I followed Professor Keeling’s procedures, nicely updated with some video now:
After the excitement of completing the Leeuwenhoek – like microscope (a few modifications, but in the spirit I think, and it does seem like there is a bit of variability in size and design of the scopes that Leeuwenhoek made, so I think the personal touches are ok.), I got to thinking about the Foldscopes that I recently received. They are actually a very similar concept to the Leeuwenhoek microscopes, a single lens mounted in a handheld focusing device that is held up to the eye. A teacher friend who had also received her Foldscope had sent out a note asking if anyone had assembled one. So on Sunday morning I took one of mine over to the Chipped Cup cafe across the street, got a mocha and some breakfast and got to work!
I took one of the student kits, very compact, just the scope, not all the extra collection and lighting gear of the Deluxe Kit. Save that fun stuff for later. I unfolded the directions and spread out the parts and got to work!
The directions are very well done, but it is very important to pay attention to which side is up, on both the magnets and the parts. For the magnets there is a silver side and a black side and all of the “paper” parts are printed with different colors on opposite sides so just pay attention. I had to backtrack a couple times but it all worked out in the end.
The above was one of my oops moments. See the picture on the paper and the object in my hand do not match. I popped the magnet holder out, flipped it around and was back on track. (shown below).
The whole assembly was less than an hour, with mocha.
I went home and assembled one more.
Now a group of us are talking about getting together and experimenting to develop our Foldscope skills in preparation for the warm weather and Leeuwenhoek Day, September 7th, 2018!
This was my first photo through the Foldscope. I chose a flea in honor of one of Robert Hooke’s famous drawings from Micrographia.