Monday, August 19, 2013

Cross Frame

I started building the first carbon cross frame.  It uses custom ENVE tubing, ENVE seat and chain stays (for cantilever brakes).

Here are the main triangle tubes mitered in the jig.  I carefully mark them before cutting to avoid any screw ups.

The ends of the ENVE seat stays come molded to bolt directly to dropouts.  I noticed the spacing was a little off for the Crumpton dropouts I'm using.  I set them up in the mill and carefully ground them down to fit.

Once I had them completed I fit them on the dropouts and checked the cantilever post location.  It was out by almost 1/2"!  This seat stay molding was obviously for a dropout with more offset from the axle.  ENVE did not supply a drawing when requested so I was hoping for the best.  Turns out I had some cutting and machining to do.

I cut the molded end with threaded insert off the stay and tried the Crumpton seat stay plug.  Still over 1/2" short given the amount I had to remove to eliminate the molded end.
My only real option was to machine a new set of stay end plugs with the correct offset.
In the end they turned out better than I'd hoped.  Now they just need anodizing.


Tabi Ferguson said...

Squeee!! This one's for me!

Crash said...

Hey Man- this looks great! The guys at ENVE seem to have checked out for us small builders. The days are gone when I'd call them and talk with an engineer.