Evenness of arrangement of printed letters on any given line.

Bail Rolls


Rubber or composition rollers mounted upon a frame assembly that press lightly against the upper surface of the platen and hold paper down while being fed through the typewriter.

Base Rail 

The rail or track upon which the carriage and its component carriage rail rest and ride upon carriage bearings.


A surface in which a shaft or pivot rests and turns freely while being held from all other motion except rotation.



The section of the typewriter that rides back and forth on the base rail, providing movement for spacing and mounts for the platen and feed rolls.

Carriage Bearings 

Spherical or cylindrical rollers held between the carriage and base rails upon which the carriage assembly moves forward and back.

Carriage End Stops 

Final limits to the travel of the carriage, both left and right sides, if the carriage has bypassed the margins through use of the margin release.

Carriage Rail

The integrated part of the carriage that provides a track for the movement of carriage bearings.

Carriage Release

A lever, mounted on either or both sides of the carriage, that disengages the escapement mechanism and allows the carriage to roll freely from side to side.



A cord that connects the carriage end to the mainspring assembly and pulls the carriage across rails.



A gear or wheel assembly that engages the teeth on the star wheel, and govern the letter spacing.

Feed Rolls


Rubber rollers mounted under and pressing against the platen, serving the purpose of holding paper tightly in position while being fed through the machine.

free css templates



The printed result of type striking paper, using an inked ribbon for visibility of symbols.

Key Lever


The stem upon which the key top is mounted.

Key Top 

A part mounted on the key lever that show the symbol or letter being printed, while being struck by the finger of the typist.

Lateral Guide


A movable tab mounted on the face of the paper table that aligns the leading edge of the paper with the front scale on the carriage.

Line Gauge

A device usually mounted on the platen that indicates available number of lines on paper.

Line Space Control

A lever or tab which when set to different positions adjusts the line-spacing pawl to one, two or three line-spacing.


Any mechanical part that joins together separately classified sections that work in conjunction.



Spring that provides the source of power necessary to pull the carriage across the rails.

Mainspring Drum/Cage

The housing that contains the mainspring.


Movable stops that adjust the length of carriage travel to the width of the paper being used.

Margin Bail

On machines using an automatic margin setting principle, this is a bar, equal in length to the amount of margin travel, that disengages margin from rack and allows freedom of movement for resetting.

Margin Control

Manual means by which margins are moved to desired positions.

Margin Release 

A manually operated key or lever that moves the center post out of contact with the margin, so that typing may be continued past the preset stop.

Margin Scale

A repetition of the front carriage scale, indicating the number of spaces on the line of type.

Paper Release


A manual operated lever that releases the tension holding the feed rolls in place and allows paper to be withdrawn from between the rollers.

Paper Table

A metal cover, carriage length, usually over the margins, that serves as a support for that parrot of a sheet of paper not being held by the platen and feed rolls.


A small gear, mounted on the star wheel shaft, that meshes with the escapement rack and transmits movement from the star wheel to the carriage.


A term used to denote the number of spaces to the inch.

Platen Knob

Knob at the end of the platen shaft used to rotate the platen manually.

Platen Shaft

Axis or pivots of the platen, held in the platen bearing, that provides center of rotation.

Ribbon Drive


The mechanical components in a machine that cause the ribbon to feed through and reverse when the end is reached.

Ribbon Lift Arm

The lever that attaches to the vibrator and lifts it into print position.

Ribbon Spool

The drum on which the ribbon winds and unwinds.



A numerically calibrated strip on the carriage that designates spacing positions.


Semicircular mount for type bars.


A hazy impression of a character bordering on the opposite side of the sharper side printed image.

Shift Lock

A pawl that holds type bar section in upper-case position.


A large toothed wheel, with the pinion mounted upon its shaft, that engages and hold against the escapement gear.



A mechanical feature on the typewriter that allows the operator to select stops positions for carriage whiling, doing columnar work.

Tab Blade

The part of the tabulator mechanism that engages and holds the carriage by means of the tab stop.

Tab Clear

A lever that restores the tab stops to neutral position.

Tab Set

A lever that moves the tab stop into an engaging position.

Tab Stop

A metal limit, one of many on the tabulator rack, that engages the tab blade and stops the carriage at preset positions.

Touch Control

A feature on typewriters that allows the operator to select the amount of tension on the key levers.

Type Bar

The medium for carrying the type slug to print position.

Type Bar Link

The connecting link between type bar and sub-lever.

Type Guide

A slotted addition to the segment that controls the position of the type bars at the print point.

Type Slug (Type Head)

Printing agent, mounted on the type bar, that contacts the surface of paper and creates impression of the symbol.

Universal Bar


A hinged bar, mounted in back of the segment, that is pushed by the type bars and causes escapement to trip.



The part that unlocks the platen ratchet and allows the operator to select odd spacing vertically.

Variable Knob

The platen knob that contains a variable release.


The mechanism that supports the ribbon and lifts it into print position.

© Copyright 2024 TypewriterPhilosophy - All Rights Reserved