What sort of machine (router, mill, laser or other) and what sort of problems are you having?
If things that should move do then that's a good start.
Think of many Chinese machines as a kit - fully assembled (in many cases) but unfinished.
Be prepared to complete mechanical (re-assembly/alignment) and possibly other items that should have been done in the "factory" to make it work "right".
Cheers,
Harry E.
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