If you routinely perform embossing or diecutting or heavy debossing on an aluminum base, note that these "severe" operations can, over time, distort the surface of the base (not to mention the bearing and cylinder damage they potentially cause to a Vandercook proof press). For such operations Bunting Magnetics recommends a steel base.
Cylinder press packing: Grain direction
Press packing for cylinder presses has its grain direction indicated as per across the cylinder. The arrows point toward the bearers. To prevent slippage and ensure the material is serving its potential, always pack the cylinder with the grain placed properly.
In the U.S., the last number of the manufacturer's paper size, eg., 24 x 30, indicates the grain direction. However, distributors may cut up parent sheets for minimum cost outlay/maximum profit and thus supply material that could be incorrectly configured. Always inquire before purchasing press packing to make sure that you are getting the proper grain direction for the cylinder width of your press. See pic/example below (in earlier post, Drawdown Third Hand) of a tympan set (Mylar top sheet/Kimlon undersheet) supplied with wrong grain direction of undersheet.
It is also preferable to use calipered polyester press packing as a top or undersheet rather than generic “Mylar” or acetate sheeting.
Ink Roller Supports (Bearers)
Shown here is a roller support (bearer) used to ensure that the inking rollers remain at .918 as they transverse the bed. Two are used, one on either side of the form, positioned near the ends of the rollers. The use of additional bearers was commonplace when furnishing reproduction proofs and Vandercook recommended them. The bearer mark was printed with the specimen.
These are 18-pt brass bar weld (full-face) rule obtained from Caslon Limited (UK). These run the full printable length of the bed of a Vandercook SP-15. They support here two Bunting Magnetic Cerface Flat Bases. Shown also is Resalite plastic furniture.
The supports are usually chamfered and rounded at the surface edge ends to prevent roller nicking. To prevent wear on the supports the tympan is usually cut back.
Note: Temporary supports can also be made from strips of steel-backed photopolymer plate material, 18- to 24-pt wide and as long as the base. These should be placed at the edge of the base and outside of the printing area or incorporated along with the imaging.
Photopolymer Plate Pickup
A pad knife (aka tablet knife) is a very convenient tool for lifting steel-backed plates on magnetic flatbases. The blade is short enough for convenient manipulation and wide enough to prevent the plate from bending; and its front rounded edge keeps it from scratching or cutting the surface of the base.
I also use this handy tool to remove washed out plates from the platen of the photopolymer platemaking machine.
These are commonly used to separate padding and are available from various distributors of printing and binding supplies.
Humidors
Humidor boxes used for storing and handling dampened paper during editioning. These were constructed on the model described in Lewis Allen’s Printing With the Handpress. These are all from the Glen Price version produced in the early 1990s.
Press points
Steel press points are often used on cylinder presses such as a Vandercook to prevent slurring of the type at the bottom of the sheet. They are less than type high thus do not print. They are locked in the lower part of the form outside of the printing area. These catch the sheet as it flips away from the cylinder and prevent it from dragging across the type. These were Elrod cast.
Side guide
Old style Vandercook 219 brass side guide mounted on SP-15. Note flared lip (doesn't abrade the paper sheet). I prefer this to the new style Vandercook guides. Reminds me of an old steam locomotive.
Registration Tool (plate shifter)
A bookbinder's brass pallet can be used for nudging steel-backed photopolymer plates into position. This works especially well on a Bunting Cerface Magnetic Flat Base. It will not scratch the surface nor be drawn down by the base magnetism.
Drawdown Third Hand
When adjusting the cylinder packing a lowly rubber door stop can be used to prevent the tympan draw sheet from drooping down onto the inked form and/or to prevent breaking friction fingers.
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