Just to clear up a misconception: Two nuts is not necessary to eliminate backlash.
Another way to go is to use special nuts where the offset is built in. Often oversize balls are also used to achieve preload. That makes them much more compact than the 2-nut variety. Go to the web sites of THK, NSK, Bosch-Rexroth (Star), and others. There you can find specifications and scetches of how they are built.
There is also a cheaper solution from Isel where the nut can be adjusted by squeezing it just like we know from Acme screws. Probably good enough for hobby use. |