The Windkey and the Lamplighter

So, sometime last summer I was out skating on the Minuteman Trail, and
somehow I lost a wheel. Like, the whole thing—wheel, bearing, axel
and all. I’m really not sure how I managed to lose it and not notice
until I started to lose a second one, but we never found it—even
though we skated back the same way we had come. Someone must have
picked it up for me or something. So I learned that I could skate
with only a front and back wheel on one of my skates, but it wasn’t
much fun.

I quickly discovered that while wheels and bearings were really easy to
replace (and I needed new ones anyway) axels are really tricky. My
skates are a weird brand (CCM, which mostly makes hockey skates) and
the manufacturer doesn’t make them anymore, so I can’t just buy parts
from them. No worries—they’re really just standoffs with hex-keyed
screws, one of which is built-in. Perfectly normal standoffs will
work fine, if I can figure out what size.

I finally remembered to bring my calipers home and measure the
bearings for my inline skates. The internet tells me they’re usually
7mm or 8mm, and mine are .312 inches, so they must be 8mm. The space
between the "blades" is 1.15 inches wide, so anything around an
inch will do nicely. Conveniently, .312 is 5/16. I should be able to
find a 5/16 inch OD standoff which is 1 inch long—shouldn’t I?

Nope. I emailed them, but the McMaster-Carr online catalogue has 1/4" and 3/8", which is
really not close enough. .315-.25 =.11", which I think is too much
slop… I guess I ought to be able to figure that out, somehow, if I
model the forces and the friction properly.

Drat. Now where do I look? I guess if I have to I could get some
stock, and access to a shop, and drill/tap them myself, but the "get
access to a shop" part is tricky. I have no metalworking tools.