Frame Fixture

For 2011 i’ve made even more improvements to the frame jig.  I’ve increase the clearance at the head tube by replacing the extruded beam with a machined beam and a new lower head tube tower.  The dropout tower has also been redesigned and now uses dummy axles supplied by Paragon Machine Works.   Every part on the jig has been looked at and has been visually cleaned up with more rounded corners and chamfered edges.

The base of the jig starts out as a 1″ thick cast-aluminum plate, blanchard ground to insure a perfectly flat surface to build the jig up from. Like the previous version, the new jig locates and HOLDS all the tubes at the proper centerline distance off the jig base. All tube contact points are stainless steel and all aluminum parts are black hard anodized to ensure smooth action and durability.

The vertical and horizontal motion of the head tube assembly is done using DUAL-VEE linear bearings and rails.  This method of motion ensures a smooth consistent feel and eliminates the racking and binding associated with other methods of motion. “Front center”, “Y”, and “H.T. Angle” measurement are all easily seen while standing in front of the assembly.

Quickly and easily adjustable plates for the seatstays and chainstays ensure that both stays are in the same plane, then holds them in place so you have both hand free to tack them.  The chainstay plate also includes interchangeable pucks that locate the stays along the frame jigs center-line, ensuring your stays are properly located without the need to scribe lines on the BB.

All measurements and angles are direct reading on the jig.  No rulers or formulas are needed to figure out how to set up the jig.  Tube blocks hold the top tube in position allowing you to remove other tubes without having to reset the whole frame.  Blocks at the seat tube and down tube locate the tubes on the exact bb centerline without having to scribe lines and visually align them every time.

The rear dropout tower slides along a 90mm x 90mm heavy duty Alu. beam. Chainstay drop is controlled by a threaded rod and handwheel allowing for quick and precise adjustments to the drop while being easily read from the front of the jig. Custom stainless “D” axles by Paragon Machine Works keep dropouts in phase with each other and include a groove at the centerline to aid in quickly checking the rear triangles position on the alignment table.

A backplate is included to mount the frame jig in a Park bike stand.