Monday, September 06, 2010

Working on Details Cont'd

Got a to work on a few more details today - including the first round of polishing for some bits that go on two frames, one steel and the other carbon.

To begin with, I'm installing a 'braze-on' front derailer mount on the carbon bike.  Because we can't braze carbon fiber, a different method of mounting is required.  This mount will be bonded with epoxy, but that's not enough for the stresses on the front derailer.  Moreover, I'd like to have the option to use band style derailers.  The seat-tube should be plenty strong, but it makes sense to add a little reinforcement for a long-term bike.  My supplier ran a day behind schedule, before a 3 day weekend.  So the inner aluminum sleeve is still at UPS, it'll get bonded in Thursday (check-in then for pix).  The sleeve will also provide a threaded base for a mounting M5 screw that will fix the derailer mount.  For now, the screw is threaded into the carbon tube.


















More pictures later, once I've finished polishing the mount.

The brake cable stops are now installed on the top tube.
  
 
 
These are bonded and riveted in place, and then the backsides of the rivets are bonded.  The holes are drilled for the derailer cable stops, but problems with the rivet tool have delayed their installation.  Should be done by Thursday.  So at this point, things are ready to clean up and start wrapping joints.  Which means that its time for me to start cleaning and organizing the space for wrapping and vacuum bagging - which will probably occur next week.

On Nick's bike (steel), we have a pump mounted to the left seat-stay.  At the bottom (drop-out), feet on the pump head sit on the chain and seat stays.  To prevent the feet from wearing out the paint, I've brazed on stainless plates.  There's a little filing left to do around the edges of the plates, and a little more polishing to be done on the plates, but they're coming along and beginning to look nice.
The curve of the pump handle necessitates a long plate on the seat-stay.

The small plate


The big plate.

And that's about it for now.

No comments: