1/2-10 tpi acme is very common here in the states. A tap will cost around $45. 20 turns per inch sounds like a lot of winding to me. I was not concerned about the strength of the thread, but how the weight can affect the screw.
-Tim ----- Original Message ----- From: "Bill Bulkeley" <bulke...@mmnet.com.au> To: <legacy-ornamental-mills@googlegroups.com> Sent: Sunday, August 17, 2014 2:43 AM Subject: RE: Shop made Z-axis The weight is not an issue if you worried about the thread being strong enough to lift the router you just use a longer lead screw nut Thus using more thread to achieve the same strength and a metal nut. I went with a cast iron nut with mild steel leadsrew 1/2 inch dia unf 20tpi but that was what I had in the shop it worked well to stop the vibration movement. but it was not a split nut I think I would go a bit larger in dia if I had used a leadscrew nut in halves and 20 turns per inch of travel i think it was is slow but that wouldn’t matter with a split nut you could just disengage for the longer distances of travel Bill -- You received this message because you are subscribed to the Google Groups "Legacy Ornamental Mills" group. To unsubscribe from this group and stop receiving emails from it, send an email to legacy-ornamental-mills+unsubscr...@googlegroups.com. To post to this group, send email to legacy-ornamental-mills@googlegroups.com. Visit this group at http://groups.google.com/group/legacy-ornamental-mills. For more options, visit https://groups.google.com/d/optout.
