Installation and Ordering
All lead screws are shipped fully assembled and "run in" to intimately mate the screw and nut
lead screws
1. Precision Lead Screw - Manufactured of hardened, low temperature stabilized A6 tool steel, in four accuracy grades. Threads are ground and lapped. Thread to thread error as low as 0.000010" including drunkenness. Each screw is "run in" with its own nut.

2. Preloaded Nut - One piece phosphor bronze split nut is self-adjusting. Radially preloaded nut halves respond to the average lead, further reducing residual one turn screw errors. Improved design achieves increased axial stiffness and suppresses backlash.

3. Self-aligning Thrust Bushing - Multiflexured, one piece bushing transfers thrust from the nut to the external load in a theoretically ideal way. Reduces effects of residual eccentricity of lead screw and errors due to slide nonlinearity. Minimizes loading of air bearing slides.
  4. Thrust Bearing - Precision preloaded double row ball thrust bearing, in a selection of axial thrust accuracies as good as 0.000010". Thrust bearing error adds directly to the lead screw drunkenness error. Lead screw performance is compromised unless a bearing with equally small errors is selected and properly fitted. We select the best available, epoxy them in place, and retest after fitting. We can also advise you on practical techniques to achieve extreme thrust accuracies better than 0.000005"

5. Optional Lubricator - The optional lubricator, factory installed on the nut, removes dust and lubricates the screw in applications where the screw is exposed and continuous lubrication cannot be provided. Periodic reoiling of the lubricator is required; we can supply the recommended oil.

Lead screw material - A6 hardened and low temperature stabilized.
Lead Screw Diameter 1/4" 1/2" 3/4"
Maximum Available Travel 8" 25" 31"
Standard Leads* .025", .050", .100", .200"
1 mm, 2 mm, 4 mm
.025", .040", .050", .100", .125", .200", .400"
1 mm, 1.25 mm, 2 mm,
2.5 mm, 4 mm, 5 mm
.025", .050", .100", .200"
1 mm, 2 mm, 2.5 mm, 5 mm
Maximum No-load Torque 4 oz in 8 oz in 12 oz in
Maximum Load
(Including Inertial)
30 lb 50 lb 100 lb
Working Load
(Including Inertial)
8 lb 10 lb 20 lb
Stiffness of Nut 4 lb /.0001" 5 lb /.0001" 8 lb /.0001"
*Other leads available by special quote.

Lead Accuracy Specification
.000050"/ turn
.000100"/ inch
.0004"/ foot
.000010"/ turn
.000025"/ inch
.0002"/ foot
.000025"/ turn
.000050"/ inch
.0002"/ foot
.000010"/ turn
.000025"/ inch
.0001"/ foot

Bearing Thrust Plane Accuracy
Standard- .000030"
Available- .000015"

30 Chambers St., Fairfield, Connecticut 06825
Tel: 203/336-1849 Fax: 203/366-1326
E-mail: Sales

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