As I was trying to answer a user on how to scale up a 3d printer. I had the thought that most of the time you don’t need to scale up everything you just want to be able to print things that are longer than normal. The solution I hit on is using a silicon conveyor belt. A printbed wide driver wheel with geared teeth on the edges to make sure you get a steady movement. Your print area would have to be super smooth so the belt glides over it possibly a coating of Teflon to assist it.
Problems I can see,
Any little bump is going to make your print pop free.
Speed control will be critical
Heating might be a issue as the belt moves along cooler unheated silicon might not have the same adhesive properties as heated silicon.
Belt slippage
Benefits
You can by extending the bed print things as long as you want.
When prints are done they can be automatically slid off the bed and into a storage bin.
You can easily convert most standard RepPap printers to use this
Thanks Mike