S By A-A-59334\)This specification covers electric motor driven, metal turning and threading, engine and toolroom lathes. The lathes shall have either geared head drive or combination gear and belt drive with equipment and accessories as described herein.

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MIL-L-23400E

3.3.7 Dials. Rotating dials or handwheels shall be used for longitudinal

movement or cross motion and shall be graduated in increments not greater

Such

than 0.010 inch for longitudinal and 0.001 inch for cross motion.

graduations shall accurately indicate machine component movement or material

removal. Dial and handwheel circumferences shall be permanently and legibly

engraved or etched on a nonglare background and be of such size that gradua-

Feed dials shall

tions can be read from the operator's normal position.

have independent zero adjustments and shall be calibrated in such a manner

that the last dial graduation progresses into and is continuous with the

first dial graduation as the dial is rotated through the zero position.

3.3.8

Gears .

All gears and pinions of spindle and axis drive trains

selected for use in the lathe shall be designed and manufactured in accord-

ance with AGMA 390.03 and AGMA 360.02 for the English (US) or ISO 54 for the

All back gears, gears in the headstock, gears in the

metric (SI) system.

quick change gear box, and gears in the drive train shall be hardened steel.

The gears shall be proper width and size to transmit full-rated torque and

horsepower through the speed ranges without failure for the expected service

life of the machine. The hardness of the gears shall be not less than Rock-

well C-48.

3.3.9 Electromagnetic interference control.

When specified (see 6.2.1),

equipment furnished under this specification shall comply with MIL-STD-461.

The equipment and subsystems class and the emission and susceptibility

requirements shall be as specified.

3.4 Components. Each lathe shall consist essentially of a bed and base,

headstock, headstock spindle, spindle drive, spindle speed change mechanism,

carriage and apron, feed mechanism, cross slide, compound rest, and tail-

In addition, the machine shall have all other equipment speci-

stock.

fically described herein and all additional equipment necessary for the

machine to meet all of the performance requirements stated herein.

3.4.1 Bed and base. The lathe shall have a bed and base structure that

supports the headstock, tailstock, carriage and other related equipment.

The bed shall be a stress relieved ferrous casting with sufficient strength

and rigidity to maintain accurate alignment of all the components in accord-

ance with ANSI B5.16. The bed shall have V-ways or flat ways or a combina-

tion of "V" and flat ways to provide a sliding surface for t-he longitudinal

movement of the carriage and assure alignment of the headstock and tail-

stock. The bed ways shall be either cast integrally with the bed structure

or replaceable way inserts, or a combination thereof. The bed ways for the

carriage longitudinal movement shall be hardened to Rockwell C-5C if

integral or Rockwell C-55 if inserted, and ground to minimize wear and maint-

ain accuracy of alignment.

Means shall be provided to lubricate the bed

ways automatically or with a one-shot lubrication method as specified (see

6.2.1).

The bed shall have a sufficient number of covered access openings

to facilitate inspection, adjustment, and repair of components located

within the structure.

The base shall be provided with means for securing

and leveling the machine on a foundation.