Deathly Hallows - FW - Alligrater

[Deathly Hallows]

The sprockets if ordered turned up. Perfect fit - thank goodness.

Now to mount them...

The wheel profile does not have an obvious option. My idea was to make a custom mount out of HDPE that spread the load over the premoulded spokes then bolt the sprocket to this and the mount fix by glue or bolt to the wheels.

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Above you see the outside and inside profile.

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The sprocket is perfect, almost matching the hub.

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The finished mount...or so I thought

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So it fit snuggly over the 6 spokes and the hub shaft, so I thought I would give it a tap with a hammer to see how tight it was. (Above picture does not show finished mount but for illustration)

BANG - it shattered into three pieces!

So I made another, this time with wider slots. This is not going to grip the spokes tight.
I will glue it in place with the fine two part araldite mentioned above.

But before I do that I want to fix into it bolts to hold the sprocket in place. I will use the heated and countersunk method, allowing me to fix the nuts on the outside also with some thread glue to stop them moving.

I also realize that the depth of the mount is too shallow as the revised version sits flat to the end of the raised hub. This gives very little clearance for the chain, perhaps only 3-5 mm, which would be enough if there was no flexing or movement but I think to big a risk, so I need to build a bigger block.

EDIT: While walking the dog I concluded I will stick with it and buy some 20mm HDPE, perhaps a piece of 30mm too.