New router build advice...

[Kitwn]

Next option and one I'd suggest you consider is using a belt drive.? It gives a combination of Screws and Rack. It's very efficient at around 80% with low backlash and if done correctly can give very close to the ball-screw performance. It still requires gearing to give you the correct feeds etc but with much less hassle than R&P gives regards setup and adjustment.

This is the first comment I remember seeing about the potential relative performance of belt drives, they don't seem very popular but have a lot going for them. Have you seen the Everman variation aimed at reducing belt stretch? This link is to the US patent for the design.
https://patents.google.com/patent/US20090301237

[JAZZCNC]

This is the first comment I remember seeing about the potential relative performance of belt drives, they don't seem very popular but have a lot going for them. Have you seen the Everman variation aimed at reducing belt stretch? This link is to the US patent for the design.
https://patents.google.com/patent/US20090301237

I was involved in the thread on CNCZone with Mike Everman who designed this system long before the patent went in and I've built 2 machines using this setup, and 6 machines in total using a belt drive. However, I moved away from it because ball-screws came down so much in price it wasn't worth the trouble for small to medium machines I mostly build. While belts are a good choice for larger machines they do put restraints on the machine regards the best place to locate them to avoid debris, then you have wear and maintenance to consider. Ball-screws are much simpler and far less maintenance.