Checking the other full scale frame drawing for the chain stays. I can measure the chain stay angle (8.5*).

full size frame view
frame chain stay view.

Because the are Columbus Spirit chain stays they are flared and ovalised i can’t use a tube mitre program so the tube notcher is out again.

tube nothcer

When both are are done it time to fit up on the jig to check they are the same length.
Chain stay on jig

It’s best to do one side at a time with a couple of small tacks to see if it’s square.
Chain stay vertical to plan

On the plan its square in the plan view but not on its side. Dam. that’s why you tack and check. So brake those tacks and adjust the jig by 4 mm and do it all again.

Chain stay on plan

The quickest way to get the other chain stay on is to use a dummy axle set to 132 (+2 mm of the final axle width as the bridge will pull it together). tacked and time to check with a real wheel.

frame rear end alignment with dummy wheel.
frame rear end alignment with dummy wheel.

Bang on sorted. Seat stays next.

Advertisements