Hi All!
A bad head cold has stoppered my plans to camp-tour on the Carradice-equipped Nomad during this weekend's fantastically good 27°C/81°F weather. To temper my disappointment, I mowed the lawns and then retired to the garage to play with my tools.
I milled a new shifter pod from billet aluminum. While I loved the original shifters and have them on a couple other bicycles, I wanted to use modern indexed shift levers on one early-'80s bicycle. It had an "aero" top-mounted downtube boss incompatible with anything but the proprietary friction-shifting levers designed for it (
http://www.bikeforums.net/classic-vintage/514867-test-your-wits-suntour-symmetric-reassembly-challenge-pics.html ...and...
https://www.youtube.com/watch?v=FyR9Sezf1PM ). Worse, the large square brazed-on frame boss was threaded M6 x 0.75 (fine), not the usual M6 x 1.0 thread pitch. The frame boss is too shallow to rethread and is a blind hole, so I had to reuse the original mounting bolt, as no replacements are readily available here with a socket head.
I wanted to maintain as much of the original appearance as possible, so no quick-and-easy clamp-on adapters for me; my pod is modeled after an mid-'80s SunTour design. The shift lever posts were made using a small holesaw to make plunge cuts to the desire depth, then milling away unneeded material. Now, all I have to do is finish removing the tool marks and polish the aluminum and it will be ready to install.
Figuring someone might be interested in making their own parts, I've attached a few photos showing the shifter pod in rough finish and about half polished. Aluminum is pretty soft, so it is not too difficult to "carve" with simple tools as you might whittle on a block of wood with a knife. In fact, I sometimes encourage people to first carve their part out of wood as a prototype. Soft balsa works well. In this case I made a drawing, then used a few electric tools to spare my hands -- electric bandsaw for roughing out the shape, drill press with drill bits and a holesaw, a Dremel Moto-Tool and some good, sharp hand files (mill, bastard, and fine cut) and an M5 x 0.8mm hand tap -- but it could all have been done with hand-powered tools.
There have been lots of fun little projects over the years. I try to make one of these little milled-aluminum projects each quarter...rack light mounts, homemade versions of the Avid Microdapter, splined-to-threaded freewheel adapters, engraved stems and cranks, and periodic reprofiling of freewheel and cassette cog teeth to compensate for wear. The aluminum comes in small billet overruns from a foundry near my home (
http://www.oregonpattern.com/ ).
I taught myself to shrink and stretch metal with a hammer and dolly and have hammer-shaped mudguards from annealed aluminum sheet-stock and also have cast 'guards from liquid ABS, then milled hollow steerer-core mounts from billet aluminum.
The brazed- or TIG'D-steel projects are a bit more advanced and require more specialized tools -- long-layback seatposts, adjustable tandem stoker stems, suspension stems, tubular cro-moly brake boosters, forks and steerers, entire front and rear racks, braze-ons for bottles/racks/mudguards and canti- or v-brakes, and entire frames all built as a hobby, not for sale. My small-wheel, full-sus Folder awaits the addition of just a few cable stops and wet paint, and the small-wheel full-sus recumbent is in progress, about half done.
I think a Carradice quick-release mount for the Nomad may be in the works.
Best,
Dan.