Any way to close off the room if an axle is entering it?

[Gazz]

This is allowed and working :

 

And while you may not be able to close off grinder / pulveriser directly...

You can put a thin (chiseled) plate in front of the input / output chests. If you cut out an opening in that plate and it is small enough the plate still counts as insulating.
Or use a trapdoor for that. They are also "closed".

It takes more braining and effort to have your engineering room "neat" but it's doable.

Edited November 1, 2025 by Gazz