I had a small feeling someone might bring this up, and I have put some thought into it.

I thought about building the shovel first but I realised that I would end up building two robots if I were to then build a spinner afterwords. As changing the chasis might cause a bit of a problem so it'd actually be cheaper to build the spinner first.

The plan was I'd design the robot to have a drum at the front , but I'd only apply teeth once I had finished the entirety of the bot, and even then the teeth won't be sharp, and are most likely to be blocks.

That or I'd design the robot to have the space to hold the tech needed for the spinner and build the shovel to start, then go back to it once I have more experience. One problem I found with that was that I might not be able to accurately predict size and weight of each part needed for the spinner, and the best way to work it out would be to buy the parts, which would mean I'd have the bits and bobs sitting around my workshop for sometime.

*shrug*

Without teeth the drum would just be as hazardous as having a pillar drill or grinder. Probably less so.

I'm probably totally wrong.