Saturday, 9 November 2019


                         As an introduction though, why not go to the Blog overview first.

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Hubs/stub axles/wheels.

Specially manufactured to my specification, these are not "off the shelf " items. Splined hubs have been around since the firm Rudge Whitworth introduced them prior to WW1. Post WW1, many motor manufacturers began to use them, specifically MG and Riley in the 1930s, other manufacturers of sports cars following suit. I specifically wished to get the centre point steering/scrub radius, and in "old money" the king pin inclination angle as close as possible to the theory, which in effect is a line drawn through the top and bottom ball joints through to the steering arm ball joint, when projected, should intersect the centre of the wheel/tyre, or at least be close to it or to the tyres inner edge. Modern car wheels can more easily achieve this due to a large wheel offset.

These specially made alloy uprights use interference fit top hat inserts top and bottom into which the ball joints fit. I now modify the front top mudguard stay thread by drilling this out to 8mm all the way through, filing a flat on the opposite side, so that an 8mm bolt washer and nylock nut can be fitted.

Just a stub axle you might think, however I have these made to my own specification, again so that the wheel can be brought in on the hub to achieve the best possible KPI/scrub angle using 19 inch wire wheels.

Stub axle shown inserted into the upright.

Rear of the alloy upright showing a spacer. A nylock nut is fitted and torqued up to 50lbs.

A 5mm stainless steel spacer fits between the disc and the splined hub.


An interesting shot just to show the assembly bolted up with a wheel attached. In this shot it can be seen that the wheels are "outer laced", that is the spokes are to the outer of the wheel rim, rather than to the centre, as other wheels can be, and this brings the wheel in closer too, so that the KPI/scrub angle etc is maximised.

Now to the modification mentioned above. The tool shown inserted is a helicoil removal tool, just a triangular taper that grips the helicoil and unscrews it out. 6mm helicoils are inserted originally and I bolted mudguard stays at this point, but we've subsequently found that the 6mm bolts shear from vibration, so I decided to drill them out and hold the mudguard stay with an 8mm bolt and nylock nut.

Close up of the helicoil removal tool.

Here the upright is shown securely clamped on to the pillar drill table, enabling a perpendicular hole to be drilled. We've all tried drilling without securing things to a surface, always hold it down securely or accidents and damage can occur.

Here can be seen both uprights drilled through, before and after a flat has been filed so that a washer and nylock nut can be fitted holding the forward mudguard stay in place.

Finally the mudguard stay held by an 8mm socket cap head bolt, washer and nylock nut, which is much stronger than the original 6mm bolt in a blind hole. The mudguard stays look good when polished, and maybe the upright castings could be painted a contrasting colour?

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