...My nice new gear was useless! The original one however, is still perfect....
KMR Electronics is making new non-still worm gears using a black plastic that is supposed to be crackproof. Also they are recommending a silicone lube instead of petroleum. The combination should be doubly safe.
The still-frame gears they are selling are still made from the original plastic. My local repair guy is putting the non-still worm gears in former still-frame machines, disabling the former still picture capability, to avoid having to use the original type plastic. I have heard that the original type plastic will crack from using petroleum grease, or just from being subjected to temperature change. Or maybe just from speaking to it harshly?
There is also a company in Australia making new type plastic gears, so I heard. I don't know who this is however.