Crankshaft machining

[Mick J]

Just wondering if anyone has tried machining any part of the crankshaft? I want to add an extension piece to the ignition (right) side of my crankshaft, with a keyway. I am thinking along the lines of boring out the centre of the end where the advance retard would be and press fitting a spigot shaft and tig welding it (obviously minimal weld and protecting the part where the bearing runs from excessive heat). I have no idea of how hard the material will be and if normal cobalt tipped tooling will cope with it, I expect it will be induction hardened where the bearings run, but I don't want to ruin the end web trying to find out. I have heard of the end being re drilled for another pin when the drive pin for the advance unit has sheared, I was wondering if anyone has any first hand experience, or any other ideas for attaching an extension shaft? Thanks guys, cheers Mick

[Al]

How about a hollow shaft with a shoulder on the inboard end. Shoulder detail is a mimic of the base of the advance and retard unit so uses the pin and slot to locate it. Longer bolt through the middle and away you go.
AL

[Mick J]

Thanks Al, certainly worth some thought, my only reservation would be how much torque it would take before it let go. I am considering all options at this stage, cheers, Mick