Making a key

[AntonLargiader]

A friend of mine is into microscopes and says the correct tool is hard to come by, and often made from aluminum so it doesn't scratch the instrument. Here's an example (although this one is steel):

[SHADOW]

Every Nikon I have worked on is metric. That sounds like a 1.27mm.

[Jim Stewart]

Every Nikon I have worked on is metric. That sounds like a 1.27mm.

1.27 mm? Odd. Funny thing, it sorta rings a bell with me. Lessee: 1.27 X 2 = 2.54.

Hmmm. Why does that number seem familiar?

-js

[Noitoen]

Strange but this metric set has some strage dimensions I supose there are sockets too

[Davidhcnc]

Here is how I made a small wrench from a socket cap screw. The hex is 2.5 mm. Maybe you can find and use a suitable hardened socket cap screw.

edit Click pic for full size.

[Smokedaddy]

Well I gave this a shot this morning. The smallest allen head cap screw I had required a 2mm allen wrench. I had to turn down the head of the cap screw to 3.22mm so it would fit into the bore of the microscope turret. Unfortunately the allen key inside the turrent isn't 2mm, so I'll assume that my original somewhat accurate measurement was correct at 1.27mm (0.050"), guessing of course. Anyone know where I can buy a #0 maybe 1/2" long cap screw as shown in that chart I posted above? I wonder if they are somewhat common and I can pick one up at ACE Hardware?

[DDF47]

#2-56 set screw has a .050 hex.

[Smokedaddy]

#2-56 set screw has a .050 hex.

I'm not totally bolt/screw savvy. Have a link?

[SHADOW]

Most hardware store have metric fasteners. Try a 2.5mm set screw.

[DDF47]

Oops! 4-40 set screw has a .050” hex socket. My bad.

[Joel]

There is a link to a 1" SS 4-40 with .050 hex in post #5.
It seems likely that one can be obtained locally at a good hardware store.

[Noitoen]

This one has a .05 hex (3-48 set screw) The direct link does't work https://www.mcmaster.com/screws/thre...type~headless/

[old mart]

As already mentioned, a 2.5mm grub screw (setscrew) has that elusive 1.27mm, (0.050") hexagon socket in it.

[Noitoen]

As already mentioned, a 2.5mm grub screw (setscrew) has that elusive 1.27mm, (0.050") hexagon socket in it.

Not all, some are near enough but are 1.3mm. It seems strange for metric but you can get 1.6mm and 1.4mm screws. I suppose that small size they go in 0.1mm increments

[Smokedaddy]

Looks like the 0.050" didn't work. On another note. Anyone know of a accurate way of measuring the key? None of my calipers are able to reach the key in the turret. I tried using a gum eraser to get a impression but I'm not sure how accurate that method is. I used ImageJ to take a few measurements.