I began repair on the Custom Razor by feeding the Kevlar shock cord leader back through the motor mount. It was the elastic that broke, but the remaining bit was too thoroughly cooked to untie, and if I cut off the Kevlar the remainder would have been too short. I suppose I could have knotted a new piece of Kevlar onto the old, or abandoned the leader and just attached new elastic with a trifold mount. But on this rocket, the Kevlar was set up to be removable.
So after I cut off the elastic, I pulled the Kevlar loop off the back end of the motor tube… … and then pulled the old Kevlar out. Next I fed a new length of Kevlar through the guide straw… … and tied a loop in the end which I slipped back over the motor tube and tightened up. I marked the other end just behind the forward end of the body tube, then fed it back through the motor mount. I tied on the new piece of elastic…and fed it through. Tied the other end to the nose cone, made a loop to clip the chute to, and it’s good to go again.