Take a look on eBay Australia. There is a guy selling ACME screws in various lengths with a delrin nut included;
Leadscrew: 1/2”, 6TPI, single start rolled general purpose ACME thread. 1000mm length. No machining on ends.
Nut: UHMWPE, 27mm length. Mounting tapped for 1/4”Whitworth screws. The nut is very neat on the ACME thread and has very little play.
Search for CNC or ACME
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