Apollo Mikron 1
I hunted for this one for a long time. Most of the other Mikron 1's have a metallic handle, this has a Black plastic one. Its the same handle that is on a Busch which would indicate some collaboration between the two companies. It has Apollo Mikron embossed on the base plate (third image below) so its definitely a first generation Apollo Mikron.
This particular example arrived with a broken plastic handle as can be seen towards the bottom of the page.
There are conflicting opinions on the net, some say the middle of the 1930's and others say around 1950. If we look at the patent dates, the first patent (number DE812402) was graned on 30 Audust 1951, so I would be more inclined to believe the 1950 date. They were however only manufactured for a very short period.
Assuming that the handle remains attached to the head, this one breaks down into 4 pieces with the adjuster plate been one of the pieces, like a Busch Flexi. I've been told that the Apollo's break down into three. Again, I'm not sure if this is correct or not.
It doesn't get much use. When I do use it, I open it about a half turn. Its fairly aggressive. With some planning, it's capable of a BBS in 1pass with some buffing.
The Repairs
The first two images below show how it arrived. There were no surprises as it was shown like this on Ebay and when I saw it, I thought "WOW" - Micron 1 - I do believe that I can fix it!
My initial intention was to have the handle 3D printed by a prototyping company, but it arrived too late in the year to have it done and I wasn't patient enough to wait for the new year to use it, so decided to turn one out of nylon. The first image in the second row was the first handle that I turned for it. I found out that I definitely don't have the skills for "freehand" checkering.
Fast forward a few days, some thinking and I decided to try something else. The checkering is straight this time but the finish, although not bad, it's is not quite where I would like it. (last image of the second row) A little more hope that I will get it right so I won't be going to the original plan just yet, simply because its more fun me doing it myself.
The top of the thread of the adjuster dial was also stripped but there was still enough to use the rasor.
The Thread Repair
One evening I got the idea to squeeze the top on the twist knob in a bit. Firstly - I measured the shaft of the twist knob (7.3mm).
I then took two pieces of scrap steel bar, clamped them in a vise and drilled a 5mm hole down the middle of the two pieces.
Once I had the "pilot" hole, I then took a piece of thickish cardboard, put it between the two pieces, reclamped them and drilled a 7.5mm hole. Once I removed the cardboard I had a hole of about 7.2mm.
I then took the twist knob and slowly squeezed the shaft of it, turned it a bit squeezed again. Removing and checking it frequently, until I had it where the first few threads caught the thread of the TopCap.
The images below tell the story.