Friday 5 July 2024

Tool Boxes, Steering Locks more Casting Patterns and another Steering Damper

I had fitted new Andre steering dampers to both KTTs but was missing a damper to fit to the cammy special. I had this collection of bits and pieces.

One of the most important parts is the base of the damper – the bit that fits inside the stem of the bottom yoke that supports the entire assembly and I was missing one of those, at least, one that fitted. Rather than make one from a solid piece of steel (which would generate a lot of swarf) I made it in 2 parts

and then silver soldered them together. I have retained the original tapered locking bolt which, importantly, has a small pin that engages with the slot that I machined with a small end-mill in the base to avoid the bolt rotating when it’s tightened.

There were a few more little bits and pieces to make, shown below.

The long hexagon nut serves 2 roles: it locks the base to the steering stem with a 3/8” BSF thread whilst the other half of the nut is threaded 3/8” BSCY (which is a finer thread) into which the stud attached to the damper knob is screwed. Finally, a dome nut (will be plated later) has been made to lock the knob onto the stud and a new star spring (the Banbury Run autojumble) completes the assembly.


Mark Barker makes the most beautifully crafted toolboxes (the AJS 33/7 has one of his) and he has made me 2 that will be fitted to both KTTs which I also picked up at the autojumble.

These are not yet fitted but this is how one looks just resting in the frame tubes

and which will be fixed in place in due course using stainless steel U-bolts.

These are available in a variety of different sizes, one of which fits the frame tube exactly.

Top Tube Saddle Clip (KA-111)

The front of the seat is supported by one of these and I had  ...none. This is what it looks like in the parts book

I asked in my last blog post and also in Fishtail (Velo club magazine) if anyone had one that I could use to make a casting pattern – and now I have one. This is what it looks like in the flesh.

This one is showing its age – some brazing repair on the top part and some distortion on the bottom; nevertheless, it is quite adequate as a basis for making patterns.

I have described in some detail how I make resin casting patterns using original parts, see for example here and here so only a brief description is given below.

Various gaps and holes are filled in with wood (the large hole is filled with a piece of wood cut from a broken garden fork handle, machined to the correct diameter and cut in half to fit), body filler and thick gasket paper is added to the surfaces that will be machined on the castings to ensure there is an allowance for shrinkage.

Each of these is then suspended (in this case, using a magnet) in a small plywood box and surrounded by screws. All surfaces are liberally coated with Vaseline

before pouring silicone rubber
halfway up the parts.

After attaching conical pieces of glossy paper to each

silicone is poured to the bottom of the screws to form the top half of the mould.

The mould can now be dissassembled and used for making resin copies. This is what they look like after setting and removing the top half of the mould

and, after a bit of a cleanup, these are the finished items - 2 of each.

In addition to these resin patterns, I have also modified an existing cylinder head steady clamp (KA-43) by adding a ½” diameter boss.

This will be used as part of a steering lock assembly – see below. All these patterns are now with the foundry for casting.


Steering Lock

After fitting the petrol tanks, it was immediately apparent that steering locks were required to avoid damage to the tanks from the handlebars/clamps. It would be a pity to put a dent in these beautifully crafted tanks before they had even been painted!

To this end, I used a piece of square section solid aluminium

that I had left over from some other job to make these

and that, together with some round rubber buffers from eBay (40mm OD, 10mm ID, 20mm thick) and a head steady clamp

makes an effective steering lock.

I have modified the design slightly from the picture shown above by incorporating a boss, which will be threaded 5/16” BSF, into the KA-43 part of the clamp and so eliminating the nut and washer on the inside but I have to wait until the castings come back from the foundry to include this.


And Finally…..

I have been out and about on the AJS 33/7 Trophy recently and a buddy of mine drew my attention to a lady by the name of Florence Blenkiron. In particular, he noticed that the bike that she is riding here

Acknowledgement to whoever owns copyright of this picture

is a 1930s cammy AJS – this is the racing version rather than the off-roader that I have (see here and here). This picture was taken in 1933 so would have come out of the factory the same time as mine. To say that Florence Blenkiron was an achiever would be a serious understatement – she was the first woman to break the 100-mile per hour barrier on a motorcycle at Brooklands among other things. More details can be found on Florence here and here.

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