Page 1 of 1


Posted: Tue Oct 01, 2019 8:18 pm
by MaxP00

This one has been brewing for a while. A few weeks back I got my hands on a Wild M3 (the original model)--it's an OK scope, very well built but with the distinctive pincushion distortion that they fixed in the M3b and onward. The head as an attached focus rack which accepts a 20mm shaft. That's not the most standard size these days to say the least--I think I would basically have to find an M3 or an M5 base without a head, which would doubtless take a long time to find and would cost me more than the head itself had cost. So I decided I'd just make my own.

That part was easy enough, but of course it was an approximate fit and not very firm. Fortunately I watch a lot of Forged in Fire though so I had a good idea of how to hold everything together. I figured I'd just drill a hole lengthwise through the aluminum and steel both, insert a brass rod and then peen both ends.

So first I drilled a hole through the aluminum sans steel, since that is always easier. Then I inserted the steel and, using the hole in the aluminum as a guide, started drilling into it. Which did absolutely nothing, because as it turns out it was hardened steel rather than stainless. I had to get a carbide-tipped bit intended for drilling stone, which did the job (very slowly). I don't recommend this, don't use hardened steel.

I did eventually get through, and with a bit of adjustment could get the brass to slide through as well. However, because of all the sanding the shaft wasn't perfectly perpendicular to the base--it wanted to tilt ever so slightly to one side. That might not be a huge issue with a low power stereo scope but it annoyed the hell out of me. So before I put everything together for the final fit I slathered the shaft and holes with JB weld. Once the brass was peened in place I took a 20mm shaft collar (which I'd picked up as a drop stop ring) and pushed it down to where the shaft met the aluminum plate and tightened it in place--this provided a nice flat surface perpendicular to the shaft.

Then I held a piece of wood on the bottom of the aluminum plate and beat it with a sledge--there was just enough play between the aluminum and the brass and the unset epoxy to get everything flush. Now it was nice and perpendicular, and I let the JB weld set so it would hold that position forever.