How do YOU pack a Heidelberg Windmill?
Okay boys, my daddy always taught me to pack the Heidelberg to .040 When using the micrometer to measure the thickness, always include a sheet of tympan and a sheet of the job being printed, and fill it out with a sheet of red board and press packing till you get your 40 thousandth. It’s worked for me for the last 40 years, basically because I’ve never really thought about. recently though I was curious; if you have enough room to include a sheet of red board would you put it on top or on bottom? Would there be any benefit of printing against a hard firm surface of red board or of a soft hit of the type against a few sheets of .002?? It ain’t broke so I ain’t fixin’ but I AM curious how other old timers pack a Heidelberg. I may be old, but I’m still eager to learn something!
I haven’t used a top sheet in years, I use a piece of fiberglass foiling board taped with masking tape on the platen, then a piece of 110 index taped over that. If I’m printing envelopes I use a piece of abdick blanket taped to the platen.
I always used a hard-surface pressboard under the attached tympan sheet, with additional English-finish or bond under that to bring the total thickness (when measured with a sheet of the paper being printed) up to the caliper indicated by the gauge on the delivery upright.
I don’t know what the best thickness to start if printing on soft, thick paper expecting deep impression. I assume you would use a bit more than the thickness measured to allow sinking the plate into the paper a bit.
Then when doing make-ready, just pull a sheet of the additional packing as you replace it with spot sheets under the red board in order to maintain nearly the same packing thickness.
When printing envelopes, I do the make-ready on a sheet under the tympan (on top of the red board) to allow greater effect of the make-ready layers.
John Henry