Swingarm Jig

Wednesday 28 Nov 2012 4pm

I’ve spent the last couple of days making a jig to hold the components for the rear suspension swingarms in place while the carbon fibre/epoxy mix sets around it. I started with a piece of 3mm galvanised iron and set the pivot points accurately in place using engineer’s buttons.

This pic shows the first hole for the wheel axle already drilled and the set up for placing the hole for the swingarm pivot. A clamp is holding the second button in place while the very nears are controlling the placement.

This pic shows the set up for drilling the shock absorber pivot. I’ve machined a large button to set the distance from the swingarm pivot and I’m using a ruler and verniers to get the distance below the pivot set accurately. Drill bits are holding the button and ruler in place.

This is the end of two day’s work. It’s the finished setup for the left hand swingarm. To the left is the axle mount, made from two axle nuts welded together with a small spacer between to bring it out to the thickness of the swingarm. Next across are the two mounts for the idler wheel I’ll be using to tension the chain. Then there’s the tube (6061 aluminium) that will be the axle for the swingarm. Lastly are the two shocker pivots, held in place with a spacer between. The wooden block isn’t absolutely necessary, but helps me to control the shape of the swingarm, which is offset by 30.2mm. Next step in this process will be to make the foam core for the swingarm itself.