Steering columns explained

[SLR_dave]

Hi, it's Rob here. Regarding the plastic pin in the colapsable shaft I've used a knitting needle, just filed it down 'till it was a few thou' over size and tapped it in.

I don't mean to be overly critical, its an innovative idea, but I don't think I'd use this approach without consulting an engineer or plastics expert if I still expected the safety feature of the collapsible column to work. I mean, it may be that theres a type of knitting needle made from a suitable grade of nylon - ahh, and yeah probably not just any plastic (burrs, melts, stretches) I think, but I dont know. - I also dunno much about knitting needles either (lol).

I'd also just point out that knitting needles (as far as I know) come in a variety of styles, - I seem to recall my Gran had some thin plastic ones, but some are even alloy aren't they? (Young kids on the block definitely don't use metal!)

But just saying, if you want it to collapse if ever (hopefully never) needed, then it needs to be right, it has to sheer cleanly and not melt or foul the works (etc) with the specific types of impact it was designed for.

Each to their own of course, but if mods like that are made, I think its the sort of thing a restorer should warn any future purchaser about. Personally, I don't think this mod should be read as a recommendation without engineering certification.

There must still be some intact steering shafts available, even if pricey. I wonder if there was a compatible, or identical US GM shaft (not the whole column, just the shaft).

I don't know if the column will still collapse properly if the pins are broken, I am not clever enough to understand the shock properties of the column as a whole unit, (I'm thinking about the tensile requirements of the dash mount shear off points), I suppose Holden might be able to advise (maybe). Maybe I'll give em a call tomorrow.