I have an Vandercook No. 2 press. Very simple no inking. For packing, the number on the cylinder says .105. This seems to be a fairly thick packing. I have some sheets I received from NA graphics but this adds up to .055 including a mylar outer sheet. Any comments on what else I could use for packing? The press included a new piece of .066 rubber offset blanket. Can I use this offset blanket on this press? Thanks, Laurie Szujewska
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Does anyone have any tips for wrapping the mylar around the tympan bar? How long should the tail be?
And how does one keep it from slipping. I can’t get the mylar to wrap around tight to the bar. The packing starts to slip away from the top too. Any advice?
That press probably had a canvas underblanket originally (does it have two sets of tympan reels?). The rubber blanket is a good substitute. I use a .035″ blanket at the bottom for my .070″ undercut cylinder.
A press like the 2 was intended primarily for galley proofing of type matter. The canvas underblanket was the Kimlon of its day, resilient, not easily smashed. Sometimes they used rubber topsheets too, for resiliency. The point was to have packing that would not need frequent replacment as tympan does.
.105″is the total amount of material (packing, drawsheet and paperstock needed to bring the cylinder in contact with a printing form. However, an additional .003″ is needed to make a kiss impression (as originally intended). More would be needed for deep impression, say .110″. In other words, subtract the thickness of the paper to be printed from the undercut and add .003″ for a kiss impression and more for a bite, .005″in this example:
.023 Paper stock
.007 Drawsheet (Mylar )
.012 Tympan paper (.006 x 2)
.002 Makeready tissue
.066 Blanket
——
.110
On Your press 105 is the cylinder undercut—the amount that the cylinder face is undercut or lower that the cylinder bearers. The cylinder bearers are the outer bands of the cylinder that contacts the bed bearers, the raised smooth rails flanking the bed. Most proof presses are undercut .040, the next most common is .070. Any total amount (packing, drawsheet and paperstock) above the stated number is said to be over cylinder (i.e. .003), and is the approximate amount of impression into the paperstock.
The blanket is unused. I will try it. Two of the packing sheets I have are the Sun Pak (.016) but two of those only equals .032. Or perhaps I am misunderstanding the way this works. Is it correct to think the packing must be 105 thick for the type to print? so everything has to add up to 105? Thanks, Laurie
Yes, the .066 blanket can be used, although it might be significantly dented. You may want to place it lower in the packing order next the bare cylinder.
Other materials to consider:
Kimlon (.021”)— latex impregnated compressible paper, recovers from caliper variations, high type and other form irregularities. Good for printing halftone.
Sun Pak (.016”) — calipered manilla.
Red Press Board (.015”) — commonly used on platen presses.