The following applies to all 9", 10", 11" and 2900 Series LOGAN and WARDS Lathes equipped with Quick Change Gearboxes.

By changing a couple of gears in the Change Gear train, you will get many additional thread cutting settings in addition to the 48 as provided.

Stud Gear Gear Box Gear OR Stud Gear Gear Box Gear
48
LP-1044
72
LP-1050
32
LP-1039
48
LP-1044

Any Idler Gear may be used between the Stud Gear and the Gear Box Gear.

 
Left Hand Lever Right Hand Lever
Threads per Inch
A 6 6-3/4 7-1/2 8-1/4 8-5/8 9 9-3/4 10-1/2
B 12 13-1/2 15 16-1/2 17-1/4 18 19-1/2 21
C 24 27 30 33 34-1/2 36 39 42
D 48 54 60 66 69 72 78 84
E 96 108 120 132 138 144 156 168

Please note: This will also increase the feed-rates shown on the standard Nameplate by 33%

The Thread Indicator Dial will work as normal.  Even numbers of Threads per Inch (6, 30, 72 etc.)  can be engaged at any mark on the dial.  Odd Numbers of Threads per Inch (9, 27, 69 etc.) must be engaged at either of the 2 numbered marks on the dial.  "Half" threads (7-1/2, 16-1/2, 34-1/2 etc.) must be engaged at the SAME mark on the dial.  If cutting other fractional threads (6-3/4, 8-5/8, 17-1/4 etc) you must keep the half nut engaged at all times, withdrawing the cutter and reversing the spindle at the end of each cut.

As always, take a test cut on a piece of scrap material before committing your final work piece.

Copyright 2000, Scott S. Logan

Last updated 10/08/2003

Logan Actuator Co. - Lathe Department