The drill whines away!
A customer asked me to install a bottle cage boss on the underside of the down tube of his Specialized Amira frame.
The reason is that he does a lot of brevets, so he wants to mount a bottle (or more like a tool canister) here too.
There were already traces of an strap-type bottle cage boss being used, but
in the image above I'm positioning the bottle cage by zip-tying it
to figure out the right placement.
You can see the marks from the strap on the frame.
If you position the bottle cage too high,
the clearance with the front tire gets tight,
but if you place it too low (there's a tendency to want it as low as possible to lower the center of gravity),
the chain can rub during shifts to the inner ring.
The image above shows that moment—it's pretty close.
Whirrrr. I got the customer's permission to shift the hole about 1 to 1.5mm toward the left side,
and I drilled the pilot hole.
In the image above, the right crank is at the bottom
and the magenta accent is at the top.
From the next image onward I'm shooting from the opposite angle, but
there's no particular reason for that, so don't read anything into it.
I enlarged it to the size needed to install the rivet nut.
I installed the rivet nut and wiped down the frame, but
I couldn't completely remove the rub marks from the simple cage boss caused by vibration.
There's a method to make marks like this nearly invisible if I had the time,
but that would require a drop-off service, so I'm not doing it today.
All done.
I spent more time deliberating over the position than on the actual work.
A customer asked me to install a bottle cage boss on the underside of the down tube of his Specialized Amira frame.
The reason is that he does a lot of brevets, so he wants to mount a bottle (or more like a tool canister) here too.
There were already traces of an strap-type bottle cage boss being used, but
in the image above I'm positioning the bottle cage by zip-tying it
to figure out the right placement.
You can see the marks from the strap on the frame.
If you position the bottle cage too high,
the clearance with the front tire gets tight,
but if you place it too low (there's a tendency to want it as low as possible to lower the center of gravity),
the chain can rub during shifts to the inner ring.
The image above shows that moment—it's pretty close.
Whirrrr. I got the customer's permission to shift the hole about 1 to 1.5mm toward the left side,
and I drilled the pilot hole.
In the image above, the right crank is at the bottom
and the magenta accent is at the top.
From the next image onward I'm shooting from the opposite angle, but
there's no particular reason for that, so don't read anything into it.
I enlarged it to the size needed to install the rivet nut.
I installed the rivet nut and wiped down the frame, but
I couldn't completely remove the rub marks from the simple cage boss caused by vibration.
There's a method to make marks like this nearly invisible if I had the time,
but that would require a drop-off service, so I'm not doing it today.
All done.
I spent more time deliberating over the position than on the actual work.