Icarium

Okay, thanks! Meanwhile I also found this post which suggests other modifications to improve the moc. Maybe I will try those out as well.

Hm..don't think I have one of these. Is bricklink the proper way to try and source one? A new gear or a new axle?

Hi Zblj! Well, I already tried a few different ones. I assume with your experience the suggestion means there actually are pairs that are tight enough, right? I had just given up searching after a few failed attempts.

I tried assembling an 8043 (that I got from ebay) last night and I find the instructions on page 36 of the first manual somewhat puzzling. You can find it at brickinstructions. It seems the tiny 8 teeth gear just goes on the end of the three long axle and there is nothing to secure it further. Now I have some light gray 8 tooth gears where this works reasonably well but the darker gray one just falls off. What am I doing wrong?