Friday, March 16, 2012

Martins fork...

A quick walk through building some Ti forks...

Cutting to rough length on the cold saw...

 Once cut, into the die bender it goes to get the unicrown shape...
 All bent up to the same degree tolerance so they maintain symetry...
 Loading the blades into the horizontal mill with the fork fixture set up for the offset...
 After the cut and all cleaned up...
 A nice tight fit, should make for a strong joint...
 Time to work on the crown race base, milling out the inner diameter to press fit on the steer tube...
 The final id as measured with a T mic...
 The next step is the careful turning of the outer diameter to a very tight tolerance to permit the crown race to press tightly in place.  Too much material and the race will not press on, too loose and it will warp after welding or not hold the race at all...
 Once the od is set, using a parting tool to separate the crown base...
 The finished piece, ready to press on the steer tube and weld in place...
 Three forks started, two standard 9mm dropouts, the last (on the left) shows Martin's fork stock, which will allow me to machine out a 15mm axel dropout with an adjustable insert to allow for fine tuning of the quick release position...
 Mitering the dropout end to meet the axle to crown dimension...

 All mitered up, cleaned, and ready for tacking in the fixture.  These pieces will be plugged and purged before the welder is turned on...

A closer look at the crown base welded and machined, ready for the blades to be attached...

On hot single pass on the forks, watching the keyhole open up and closing it up with the filler wire...




Next up, making the post mount fixture...

cheers,

rody

1 comment:

dicky said...

... and how 'bout the 15mm dropout?