Spoilboard / Vacuum table + Rotary axis

Unless you want to do rotary work that would allow you to move past your Y (True 4th axis work)

If you’re just doing “turkey on a spit” work it would be fine.

There’s some good chat about 4th axis rotary here: Adaptive toolpaths for alum?

You can see some videos I’ve done where I utilize all 4 axes at once to carve letters into something on the rotary.

You might ask @jjneeb about how he has his rotary mounted