The SX4 is definitely an upgrade from any of the other Sieg mills, is it much more rigid and starts to cross the boundary from mini mill to decent size bench mill - yes spindle speed is not ideal but that can be fixed to a limit.

Axminster may have a few more of their SX4's without DROs. They have removed them from their catalogue and I managed to pick up one for £2k. They only advertise the version with DRO now. If you give them a call you may be lucky.

The spindle speed is an issue but the stock bearings are good for up to 7k rpm so a pulley change will solve that. If you want to go higher than 7k then there are better bearings available.

I've converted mine with Clearpath servos and Centroid Acorn controller.

So far so good, have managed to make a few parts but still have a lot of modifications to make- including getting closer to the 7k rpm target and waiting for the correct length ballscrews to arrive (got sent a short Y axis and bent Z axis).

I considered AMADEAL and visited them in London - nice people but they didn't have the AMAT45 (SX4 size) in stock and their gear head versions are too noisy (got to keep the wife happy). Thats the same reason I didn't go for the Warco - variable speed is easy to control with the Centroid Acorn.
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