where can I find the 1500mm lead screw? Openbuilds offers a 1000mm unit but nothing for the 1500mm length... anybody have a source? Thanks!
1000mm is about the extent of their workable length. They tend to whip when they get that long. If you want to go 1500mm you'll need to go to a larger size screw. There are several examples on the forum of other projects using larger screws. Research them a bit as most will indicate what size was used and their sources for both the screw and the matching threaded nut.
That's a good question to which I don't have a good answer. You might try scanning through the build section for ones built with leadscrews. CNC ROUTER BUILDS | OpenBuilds
dakman | OpenBuilds - Found a Canadian company that sells 8mm and 12mm stainless acme screws with anti-backlash nuts for around $60US. Lengths up to 2000mm on the M12, 4 start, 3 pitch. Up to 1800mm on the M8, 4 start, 2 pitch. Looks like these will fit the OpenBuilds nuts too... Going to have a lot of whip at that length unless you come up with some way to support them. Unfortunately, they are closed until May 15. SNB Solutions - 11. ACME Lead Screws - SNB Solutions
Quite some time ago I did a lot of research on screws, and the like, and I seem to have forgotten most of it though. I really would like to use 12mm screws, but I have great difficulties in finding one that has all the other necessary values, i.e. 4 Start, and equivalent pitch. I don't want to change the speed either really. It would be great if someone could supply a list of equivalent screws with similar values, plus matching bearings. (That's a hint by the way.) Gray