Why not combine a lust for precision equipment and fly fishing....build bamboo flyrods? I have been a bamboo rod builder for many years now and acquiring metal lathes, planes, measuring devices, etc and trying to building bamboo rods to the 1/1000 of an inch is lots of fun. My standard is if I'm less than 5/1000 from the target taper, I'm happy and I don't think the fish care!! In addition this past time allows you to design and build your own "precision" tools, like planing forms, for rod construction. At the end of the day, I can't really say a bamboo rod is better than a modern graphite rod. It just does things in a different way and both will catch fish. But to be out on the stream with a beautiful rod you've built yourself, flies from your own bench and catching fish, it's a pretty fulfilling endeavour.
Also having all this equipment has come in handy for my other passion, photography. Building pinhole and view cameras has been lots of fun over the last couple of years. The metal lathe came in handy for turning a battery adapter for a Nikon F Photomic battery compartment.
I think for me having precision equipment fulfills the same desire for the actual hands on involvement with a an endeavour that film has for photography.