Sherline 4417Z – Lathe Leadscrew Backlash Lock
Sherline 4417 – Lathe LeadscrewBacklash LockCNC machining operations require precise leadscrew movement toproducing a good part. The normal backlash of .003′ to .005′ can beunacceptable in these situations and a way was needed to reducebacklash to the .001′ to .002′ range. This solution was developedfor the Z-axis on the mill, but it has been adapted here to work onthe lathe as well.Sherline lathes have never been fitted with locking levers onthe leadscrew. This system was developed specifically for use onCNC machines. The new retrofit installation kit includes a newlocking lever and a new saddle nut without a spring loaded ball tohold it in the unlocked position. The positive locking arm allowspartial locking of the lever to reduce backlash to a minimum. Thesmall detent in the locking lever that was formerly used to engagea spring-loaded ball has been retained to indicate the side of thelocking lever that should be facing the saddle nut. If the lockinglever should fail to lock against the saddle nut within theavailable arc in the back of the mill column, check to see if thelever has been installed backwards.