I've ground down several sockets using a bench grinder. I'll put the socket on an extension bar (1/4" square drive in your case) and rotate the socket against the grinding wheel. There's so many sparks produced that you could probably do a good job working in the dark. I rotate the socket 90 degrees on the bar a few times during cutting since the sprung detent ball doesn't quite keep the socket perfectly co-axial with the bar. Also, you'll want to rotate the socket WITH the surface travel direction of the wheel, and not against it or you'll likely get gouging or chatter and a less-than-round OD.
I've modified common 16mm sockets for use with Stronglight cranks, and 6mm sockets for truing Roval aero wheels. I even did a paper-thin one once for use on an instrument manufacturing line. It developed cracks as expected, but worked for years as it was only 5.5 or 7mm thus the torque level was quite low.
Just don't get carried away and start spinning all sorts of bike parts, (like QR shafts and stem quill bolts) against that grinder. I remember once using the grinder to turn a nail-head 14g aero spoke into a T-head 15g(!) aero spoke for my rear Roval wheel.
David Snyder Auburn, CA usa
> Hi everyone,
>
> I'm looking for a socket or a wrench that will fit the locknut on an old
> Simplex
> retrofriction bar-end lever. It's a 7mm nut, but there is very little
> room around it and
> the socket needs a very thin wall. Thanks.
>
> Leonard Bulger
> Marblehead, MA USA