I had a batch of parts laser cut by https://fractory.com/
I had various different parts cut including wheel speed trigger wheels for both front and rear wheel speeds, and a few other unrelated parts, all cut from the same sheet of 1.5mm mild steel sheet. Most of the cost is actually in putting a sheet of steel on the machine. If I'd just wanted two parts, the cost would have been about £85 inc delivery.
I ended up having 25 parts cut in total for just under £90 delivered.
The trigger wheels I had cut all have sixteen teeth, and have an OD of around 104mm once folded (each tooth is folded and the sensor mounted at 90° to the shaft). The rear wheel speed trigger wheels are actually designed to be mounted on the inner end of the drive shaft, with sensors mounted on brackets off the side of the diff.
The sensors I'm using have a sensing range of 2.5mm, so are much less sensitive to adjustment to those that Caterham supply, so much less susceptible to mechanical damage through being set too close to their target, or not seeing the target by being too far from the target (maybe due to a flexing bracket?).
Thanks for that, Richard, and apologies for not replying sooner.
I imagine the cost of just a few rings might prove too expensive? From reading their website, your supplier would need a CAD file? I've no idea how to go about that.
I'm still waiting to hear back from GKN, but I'm fast losing patience with them....
I do have a used one if you want it foc.
Before someone snaps it up, could you possibly measure it? I/D, O/D and thickness?
I don't need one, but I think Tuck2020 does. I'll send him a message.
Thanks gents. Message sent to Clive.
Clive has been kind enough to send me a reluctor ring - thanks Clive.
I only possess a very cheap set of digital callipers, and have nothing to check their accuracy against, so I have measured several times in the hope that my results are consistent with the same kit.
Inside diameter 71.8mm
Outside diameter 93.2 mm
Thickness - 8.8mm
Depth of teeth- tricky one, approx 2.5 mm
I hope this is of some use to someone.
About 0.1mm of interference fit is needed between the ring and driveshaft shoulder, so an accurate measurement of the ring inner diameter and driveshaft shoulder outer diameter is important to ensure the right interference fit.
With the driveshaft at room temperature the ring needs to be heated in an oven to 250C or so to easily drop on to the shoulder without needing to use a press (assuming the shoulder is clean and smooth with no corrosion).