So, to the front cycle wings, purchased from Moss (part number 457-025). I had been considering the choices for how to mount them…
- on their outer or inner face?
- and, in a fixed position or turning with the wheel?
It was probably a walk around a vintage hill climb paddock that finally helped me to settle on inner face and fixed position. Both for aesthetics and how by utilising most of the two original struts, it would allow me to retain the standard headlamp mounting.
My design would use an original headlamp mount, a slightly modified wing mounting strut from the chassis bush up to a neater headlamp strut support bracket, a new curved tube from there to the edge of the cycle wing and a curved support strip under the full width of the wing. To prevent stress cracks, I insulated my bracket from the wing with the aluminium strengthening strips supplied and a thin rubber gasket, cut from an old inner tube, as shown below. To stiffen the assembly, I deleted the rubbers from the headlamp to wing strut joint.
Drawing of wing mount
Starting with a new wing mounting strut to ensure no internal corrosion weakness, it was modified by increasing the angle of the two standard bends and applying a slight twist to the top one to move the under wing support forwards to clear where the side lamp mounting screws would be. The neater headlamp support bracket mount was made by cutting a 5mm thick mild steel oval spacer to match the end of the cast bracket and welding it to the wing strut aligned with the bottom of the slots. The upper portion was then cut off flush with the spacer and the open ends of the slots filled in with weld to leave just the open end of the 21mm bore tube.
Above: 5mm thick mild steel oval spacer to match the end of the cast bracket Below: then welded to the wing strut aligned with the bottom of the slots.
Next, wooden formers were made to position the cycle wing directly above the centre line of the tyre, the gap and its rotational position determined by eye. My preference was for the wing to have the same camber as the tyre, as opposed to it being vertical. With the curved 32mm x 3mm support strip, aluminium and rubber strips clamped in place under the wing, a 21mm OD tube was double curved and fitted to bridge the gap. As it was a thick (2mm) wall tube I bent it by sand filling, plugging the open ends and heating to cherry red. I decided against tack welding so close to the aluminium and instead chose to measure and mark the position of the pieces, remove, make a simple jig and tack in place with MIG. Refitting confirmed that it was not quite in the correct position and that several more adjustments would be required before I could finish weld it.
Two views of the wooden formers in place (note the Bridgestone Ecopia 155/70R19 radials). Adrian Martin has fitted these to his TC and said that they really came into their own in very wet weather around and over the Apennines in Italy.
Tack welded assembly
Drawing of gaps
The close fit of the tube to the strip under the wing, to achieve tyre clearance, clashed with the planned position for the inner mounting screw so I changed the design to two inner screws, one either side of the tube.
I was able to retain the original loom routing by opening up the headlamp hole through into the new tube and drilling a new one at its far end for the sidelight wires.
The bottom bracket, was going to be a copy of the top one with a different angle bend. However, the reduced wing to tyre gap which I wanted to see at the bottom in the straight-ahead position virtually disappeared as the wheel steered. The only solution was to retain the under wing curved strip but braze a short-stepped tube directly onto the back of it to protrude through a hole in the wing.
To achieve the correct angle for this joint I positioned the curved strip relative to the tyre, then clamped the stepped tube to it with an M5 nut and bolt. By grinding the angle of the flat and rotating the joint, I was able to align the tube with my chosen point on the chassis rail, then remove and braze the joint. Brazing gives a smaller fillet and hence requires a smaller hole in the wing.
Clamped in place, ready for brazing.
To cut the only one chance to get it right hole in the wing, I first cut the corresponding one in the easily replaced aluminium strengthening strip, and when satisfied with its position it was easily transferred to the wing proper.
For assembly, the support tube back to the chassis would now incorporate a clamping screw where it slid over the stepped tube. The nearside chassis mount would be an oval plate requiring two new 5/16 inch holes, I just couldn’t find a way to avoid drilling the frame.
The offside chassis mount would be more complex as that plate would have to be spaced away from the frame in order to bridge the brake pipe.
The component parts.
Whilst the design had evolved to solve problems, I was happy that enough of my original intent remained.
To produce the other side, I machined a long bush which was a tight fit in the frame mounting tube at the bottom of the wing strut. Pressed it through both struts back-to-back and this time, by measurement, bent and assembled the second one as a mirror image.
I decided to install and road test to ensure steering and suspension deflection did not cause a foul before removal for finishing and powder coating.
To mount the sidelight, I positioned the car so it was sitting level, then with a marker pen inked the ridge and drew a spirit level held horizontal across it to identify the crown of the wing, which becomes the fore/aft centre line of its mounting flat.
The mark on the ridge has established the best position to mount the sidelight as described in the text.
The raised centre ridge was cut open and metal removed until it would press to a flat edge-to-edge joint for gas welding, filing, and drilling.
Metal removed and gas welded joint.
The result should be a horizontal flat on which to mount the sidelight ensuring an aesthetically vital vertical lens (as below).
View from the front of the finished job.
View from the rear of the finished job.
I still need to complete the water spray control comparison test against full length wings.
If you decide to do the same, please do not underestimate the time required to set the wings in a position that looks right, doesn’t foul, is aligned with the tyre, sets the sidelight horizontal and is the same on both sides.
Bob Lyell
