How-To: Make An Aperture Disc
Sean noticed a picture I uploaded to the Toolmonger Flickr pool showing a sight aperture I made the other day. One of my hobbies is tinkering with airguns, so I often undertake little projects like this for my enjoyment.

First I turned a piece of 3/4″ diameter steel on my South Bend 10K lathe.

I drilled it for the aperture (it’s a .052″ diameter aperture), threaded it 7/32″-40 tpi to fit the Williams sight, and knurled the rim. This is why I posted a Dealmonger post about the 7/32″-40 die the other day.

I parted the aperture off the bar and moved it over to my Taig lathe, to bore out the recess in the face.

Finally, I finished it with some Oxpho cold blue so it wouldn’t be too shiny. (Here the flash makes it look shinier than it is.)
A fun little project that took only about an hour — I have full details up on my airgun tinkering blog, linked below.
Sight Aperture for a Beeman (Williams) Sport [Another Airgun Blog]
My dad used to use the real ones for ‘work’ in the Army back in 1959+ in Europe…
There’s a product called ‘sight black’ that does the same thing as bluing. Flat black paint works almost as well. It’s surprising how much light can reflect off your eye and affect your sight picture.
Krylon Ultra Flat Black is a good paint for must-not-reflect surfaces.