After playing about with several iterations of differing angles to help the spur gear mesh with the newly created worms I realised that I had been angling the spin indexer in the wrong direction. I quickly placed my piece of 3mm rod under the other end of the Spin Indexer so that the nose angled down not up and then cut another gear.

Hey presto, we have a working worm and spur gear.

I also took a little video of it running in my friend’s G5 chassis.

It is a little noisy but I attribute much of that down to the etched gear frame. To confirm this diagnosis, I test fitted a proprietary gear set from Roxey Mouldings that I have in stock and that was just as noisy.