Glossary

This page is for the benefit of mechanical neophytes. It lists parts, tools and procedures not explained in operator manuals. To comment or suggest revisions please use the contact form. Acknowledgments appear at bottom of page.

Term
Backlash  clearance or amount of movement between the tooth profiles of a pair of gears in mesh. Also refers to the looseness or lost motion between worn screw threads.
Bakelite  trade name for the synthetic resin from which crank handles, adjusting and lever knobs were made. Formation is the result of a chemical action between formaldehyde and phenol.
Bearing  rolling device supporting the movement of the carriage. Comprised of ball bearings packed in grease and encased in a cylinder. See bushing and eccentric.
Bearing bars  two piece unit bracketing the roller core ends (AKA journals). Found on Vandercooks designed before the Universal series, e.g. No.4.
Bearing block  single support for the roller core ends (AKA journals). Found on the SP15.
Bed bearers  the smooth rails flanking the press bed that support the weight of the impression cylinder bearers. (Wipe clean with slightly oiled rag daily). See cylinder bearers.
Blind Hole  a hole which is bored to a certain depth of a work piece but does not pass through it, i.e. on the SP15 the hole in which the roller height adjusting post is inserted.
Brazing  a welding process that liquefies a metal as a filler material in the worn or cracked metal work piece, eg. The brass clutch plate (MB-104) on a Vandercook No. 4.
Bullet catch  a spring-loaded ball bearing latch used to hold a moving part in a temporarily fixed position or at incremental recessed positions against a bar or shaft, e.g. the sliding sheet finger sleeve on Universal and SP series presses, or the oscillator catch on a Universal I.
Bushing  a plain bearing, or sleeve, between a rotating part and an inert part, e.g. a roller core and its bearing. Material may be wood, brass, or plastic. Nyliner is the brand name for the plastic bushings that fit on the rollers cores. Used for all Vandercooks, except Universal series and SP20.
Caliper  tool used to measure the distance between two opposing sides of a part or fastener. The jaws of the caliper are adjusted to fit across the points to be measured. One jaw is fix while the other slides on a ruler. Caliper may have an additional analog dial or digital readout. Also refers to the thickness of paper and packing expressed in thousandths of and inch, e.g. .006". See paper thickness gauge.
Cam  a rotating or sliding part in a mechanism used to transform rotary motion into linear motion or vice-versa. On a Vandercook, a cam usually refers to a ramp, such as the wedges on the backside of a press which regulate whether the impression cylinder is in trip or print mode.
Cam follower  a bearing (or wheel) that rides up a cam to activate a lever at one end of it's path.
Clutch  device used to regulate the flow of power of a motor to move the carriage.
Cold-rolled teel  steel which has been passed through rollers at the steel mill to make it dimensionally uniform and smooth, e.g. galley bed plate (.050”).
Core  steel rod onto which the rubber is covered and turns insides bearings fastened at each end.
Cylinder bearers  raised outer bands of the impression cylinder. Contacts bed bearers when in print mode.
Cylinder undercut  depth in thousandths of an inch that cylinder face is lower than bearers. With cylinder at feed board, locate measurement stamped into the narrow channel separating the cylinder face from the cylinder bearers on the operation's side (040 and 070 are most common). This means that .040" (or .070") total packing is needed to make contact with a type high form locked in press bed.
Diode  on power carriage presses, an electronic component that conducts electric current in one direction (called the diode's forward direction) while blocking current in the opposite direction (the reverse direction).
Durometer  gauge and measurement scale for the hardness of rubber rollers. The higher the number the harder the rubber. Vandercook recommended a reading of 20 on "A" scale gauges. Some printers recommend a reading of 25 when using photopolymer plates.
Eccentric  bearing with an axle off center from that of the circumference to allow adjustment. Cylinder eccentrics shift the impression cylinder mode from print to trip.
Feeler gauge  tool used to measure the clearance between carriage bearings and under rails. Consisting of a number of small lengths of steel of graduated thicknesses with measurements marked on each piece. Use gauge marked in thousandths of an inch.
Fuse  on power carriage presses, an electrical protection device designed to interrupt or blow when excessive current flows to prevent overheating or fire on power carriage presses. Comprised of a glass tube containing a wire that melts when too much current flows, which interrupts the circuit in which it is connected.
Helical gear   a gear in which the teeth are cut at an angle other than a right angle across the gear face. See Korrex proof presses.
Helicoil  a threaded insert used to repair worn or damaged internal threads. It is installed in a retapped hole to bring the screw thread down to original size.
Journal  part of a shaft that turns inside of a plain bearing or bushing, e.g. roller core ends.
Journal screw  passes through roller height bearing and fastens to roller core ends (AKA journals). Some have split shanks and interior . Used on Universal and SP series Vandercooks.
Key way  a slot or recessed groove either in the shaft or gear, which is made to receive the key. See square key and Wooodruff key.
Knurl  a uniform roughened surface of either a diamond, a straight or other pattern serrations, e.g. end guides adjusting knobs and SP series gripper bars.
Limit Switches  electrical boxes with a protruding arm and wheel located on the backside of the SP25 and Universal series presses with power driven carriages. Third pary manufacturers call them microswitches.
Limit Switche Cams  the rail that hangs below the carriage and slides over the wheels of the limit switches during travel.
Nyliner  brand name for the plastic bushings that fit on the rollers cores ends. Used for most common Vandercooks models except Universal series SP20 and SP25.
Paper thickness gauge  tool used to measure the thickness of printing paper and packing materials in thousandths of an inch. (AKA micrometer, but it is technically a different tool.)
Pawl  a catch that locks against a ratchet to prevent its backward movement. See ratchet.
Plain bearing  a one or two-piece assembly consisting of a hard metal backing piece with a softer metal mated to it.
Plating  the process of depositing a layer of one metal on another, often done electrically, for the purpose of corrosion protection, appearance, improved electrical conductivity, and other engineering requirement, e.g. dull coating (zinc) on gripper bars.
Play  movement between two components either through wear or design, e.g. the lateral movement of the reel rod.
Push fit  two parts assembled under hand pressure only, e.g. the dowels, inserted into the side plates supporting the trip springs on SP series presses.
Ratchet  a gear with right-angled teeth to be engaged by a pawl that gives it intermittent motion and locked against backward movement by a pawl. The device that controls the reel rod.
SAE  (Society of Automotive Engineers) a standards development organization. Describes oil grade, e.g. SAE 20 wt oil. Also denotes measurements, in a fraction of an inch, for fasteners and tools.
Set screw  a headless screw, tightened by means of an internal hex slot. The set screw passes through a threaded hole in the outer object and is tightened against the inner object to prevent it from moving relative to the outer object. Align hole to detent (dimple) on shaft prior to fastening to reduce slippage.
Shim  a thin strip of metal or Mylar used to increase height of gear racks or position of cams. Also material, preferably metal, used to level press on shop floor.
Single-phase electric power standard residential wiring and the rate of current that most Vandercooks run. Large power carriage presses, e.g. 232P, are wired for three-phase used in commercial buildings. A phase converter may allow a large press to run at a home shop.
Solenoid  on power carriage presses, an electrical switch that convert energy into linear motion.
Sprocket  a circular plate with teeth machined around outside to engage links of a chain.
Square Key  rectangular bar that fit into a slot (key way) in a shaft and project above the shaft to fit into a mating slot (key way) in the center hole of a gear or pulley to provide a positive drive between the shaft and the gear or pulley.
Stops  devices attached to the carriage or press bed to limit travel, e.g. brackets which contact the bumper springs or the rubber wedges on a Showcard-style, e.g. No. 01.
Swedging  a cold die forging operation in which a metal component is forced into a work piece, e.g. a bumper spring into a bumper block.
Taper pin  steel rods with one end having a slightly larger diameter than the other used as a fastener.
[Thread] Tap  a hardened and tempered steel tool for cutting internal threads which has channels lengthwise to provide cutting edges for the threads and a square at the end of the shank for turning the tap with a wrench. See thread chaser and thread cutting die.
Thread chaser  similar to a tap it is a steel tool for cleaning—but not cutting—external screw threads. It has channels lengthwise to clear away dirt and a square at the end of the shank for turning the tap with a wrench. See Tap and Thread cutting die.
Thread cutting die  a hardened and tempered steel tool for cutting external screw threads. It has channels lengthwise to provide cutting edges for the threads and can be fitted into a wrench to stabilized while the screw is turned into the die. See Tap and Thread chaser.
Thread pitch  number of threads on length of screw. Expressed in fractions of an inch on Vandercook presses. A screw or bolt is specified as: 5/16 - 24 × 1¼. The first number describes the diameter, the second the threads per inch, the third the overall length.
Thread pitch gauge  reference tool determining the pitch of a thread that is on a screw or in a tapped hole.
Tie bar / tie rod  horizontal bars that connect the two carriage side plate providing structural support.
Tolerance  a fractional allowance for variation from the specifications.
Truss  rigid frame on the No. 1 Vandercook providing structural support for the impression cylinder. The first version has a double truss spanning the length of both sides of the bed, while the second version from the 1930s has a single truss on the far side.
Viscosity  the resistance to flow of oil or printing ink determined by its thickness. The thicker the substance the greater the viscosity. Unit of viscosity is centipoise.
Woodruff key  a small semi-circular keyed joint used to strengthen connection between the gear to the roller core. The key sits in a semi-circular pocket on the core called the keyway. When the key is installed, the flat surface projects to fill a slot in the gear. Not used on the No. 4 or 215 because of the clutch mechanism. Also not used on the SP15 form roller core and gear.

Acknowledgments
The following individuals have helped improve this table: Terrence Chouinard, Bob Oatman, Mark Wilden