What kind of surplus or discarded items can I find lead screws in ? Something about 6 to 10+ inches stroke. Need a pitch twice as "agressive" (or more) as a 1/2 inch #13 screw thread.
I don't mind buying them outright if I can get them for around $12 each, or better.
Enco (www.use-enco.com) sells acme threaded rod in 3 or 6 foot lengths out of their catalog. It is pretty inexpensive.
Good Luck, BobH
Leadscrews used to show up in surplus daisy-wheel printers, but those have disappeared even from surplus stores.
John Nagle wrote:
I was going to suggest 8" floppy drives, but they have gone the way of the buffalo too.
Threaded rod is not the same thing as a lead screw. Threaded rod is intended to be used for a fixed bolt/nut application, not as a linear drive. Bolts and nuts are designed to have high friction under load; lead screws are designed to have low friction under load. Lead screws are usually square or Acme cut, and are often used with ball nuts to reduce friction.
For a small lead screw, a bolt-type thread may work, but you're talking about half-inch rod, which would imply a load upwards of 100 lbs.
Here's some reasonably priced 1/2" Acme threaded rod:
They also sell the matching nut.
Also take a look at the screw jacks on this page:
There's one with a travel of 6.25", with the gear drive for connection to a motor. All for $10.95 each.
On Tue, 26 Aug 2008 02:05:03 -0400, "pogo"
3' threaded rods at Lowes and Home Depot hardware departments
Hmmmm - the only ones I have seen at Home Depot have 10-24 thread or similar. I haven't looked at Lowes yet - they have the best selection of odd hardware down in this area ( Atlanta ).
I did notice a concrete drill bit that was cheap that might work, though. anyone tried using one of those ? I would just use some of that ShapeLock plastic to form a nut if I used one of those.