Troubleshooting

This page tabulates common presswork problems encountered on a Vandercook and similar brands of flatbed cylinder proof presses. Your mileage may vary. See the Acknowledgments below. See also the Maintenance and Glossary pages. For real world proof press maintenance instruction see Workshop page. To comment or suggest revisions please use the contact form.

ProblemCausesSolutions
Impression uneven: randomly or along length of bed
  • Drawsheet/packing dented
  • Hidden overlay or uneven packing
  • Form raised by over-tightened lock-up
  • Height of form not uniform
  • Replace used drawsheet/packing
  • Standardize packing
  • Back off quoins, insert 4 picas furniture between form and quoins.
  • Mill high type or blocks
  • Remake plate
  • Add underlay to low areas
  • Add Kimlon under drawsheet
Impression uneven: across width of press bed
  • Drawsheet/packing dented
  • Hidden overlay or uneven packing
  • Form raised by over-tightened lock-up
  • Height of form not uniform
  • Under rails worn
  • Carriage bearings out of adjustment
  • Replace used drawsheet/packing
  • Standardize packing
  • Back off quoin & place 4p to form
  • Mill high type or blocks
  • Remake plate
  • Add underlay to low areas
  • Add Kimlon under drawsheet
  • Lock up type high rule parallel in bed and an inch from bearers, pull blind proof and examine for impression
  • Adjust with .003" feeler gauge between bearings & rails
Rollers inking shoulder of forms or base
  • Rollers set too low
  • Lock screws loose
  • Rollers too soft for low relief plate, i.e. polymer
  • Form rises
  • Form too high

  • Ink too loose
    • Adjust height screws, replace if stripped
    • Tighten, replace if stripped
    • Replace rollers
    • Plane form
    • Adjust press bed height if equipped
    • Mill form to .918"
    • Thicken with magnesium carbonate
    Rollers not contacting form
    • Roller lever tripped
    • .968" galley bed
    • Low form
    • Diameter undersized
    • Engage rollers
    • Install .050" bed plate
    • Print on galley
    • Add underlay
    • Replace, spec: 2.5" or 3.0" by model
    Rollers have developed flat spots
    • Prolonged contact with oscillator and drum when not in use
    • Use a rubber rejuvenator, but expect to replace rollers
    Rollers glazed
    • Oxidized by oil-based inks
    • Use a roller conditioner, e.g. Putz Pomade
    Rollers swelled, shrunk, pitted, hardened
    • Exposure to light, age, rubber dried out by solvents
    • Replace rollers
    Rollers wipe ink from form during travel
    • Rollers set too high
    • Adjust roller height
    Ink not laying correctly
    • Printing too fast
    • Form roller is sliding over form
    • Rollers hardened (durometer above A30)
    • Ink too thin
    • Ink too thick
    • Slow down operation, keep left hand firmly on top of cylinder during run of hand-cranked press
    • Tighten set screws on gears and confirm presence of Woodruff key where applicable
    • On the No.4 and 215, the gear and clutch assembly must engage during carriage travel
    • Replace rollers
    • Modify with magnesium carbonate
    • Modify with tack reducer or plate oil
    Inking unevenly
    • Ink not evenly distributed
    • Rollers unevenly set
    • Roller surfaces uneven
    • Metal Plate not secured to base
    • Polymer plate not secured to base
    • Poorly processed plate
    • High spots on form
    • debris under form
    • Add where needed
    • Wash up and re-ink
    • Adjust roller height
    • Replace rollers
    • Relock to toggles on patent base
    • Retack to wood base
    • Strip adhesive and reapply
    • Replace plate
    • Peel away drawsheet
    • Wipe down press bed and under side of form in chase or base
    Inked edges of type and images appear watery
    • Thin Ink
    • Thicken with magnesium carbonate
    • Remove excess from oscillator
    Rollers Ghosting
    • Rollers are stripped (depleted of ink by solid area then rolls onto another solid before being recharged of ink from ink drum). The images of the first solid is thus transferred to the second.
    • Add more ink to assembly
    • Plan imposition to avoid lining solids
    Slurs
    • Rollers set improperly
    • Rollers in poor condition
    • Too much ink
    • Cylinder over- or under-packed
    • Baggy packing
    • End of long sheet is unstable or "fishtails"
    • Paper grain wrong
    • Warped base
    • Form locked too tight
    • Worn bearings
    • Cylinder not riding on press bearings
    • Maladjustment of grippers or friction fingers
    • Wrinkled/cockled paper
    • Paper mis-fed to grippers
    • Readjust height
    • Replace Rollers
    • Remove ink excess from oscillator
    • Correct packing for paper on press
    • Unwind drawsheet, shift reel rod laterally
    • Use sheet fingers, tape end of sheet to drawsheet, stabilize sheet by making it wide enough to "work and turn" etc., or rotate position of form toward head of bed and turn sheet.
    • Paper grain should run across the cylinder between the bearers
    • insert press points or 5 pica furniture turn on its side so that it projects upward to prevent paper from slapping
    • Add underlay to low form
    • Back off on quoins
    • Replace bearings
    • Adjust carriage
    • Clean and lubricate gripper bar
    • Soften packing
    • Add underlay
    • Swap paper
    • Adjust end guides
    Mis-registration
    • Paper mis-fed to grippers
    • Ink not suited to the surface
    • rough handling of the freshly printed sheets
    • static electricity
    • too much ink
    • too much impression
    • extreme atmospheric conditions humidity
    • wrinkles in sheet after impression
    • feed board or paper guides too high above the drawsheet
    • curled or cockled sheet
    • grain not parallel with cylinder axis
    • incorrect setting of grippers or fingers
    • air pockets produced by form elements, board keylines
    • Slow down operation, keep left hand firmly on top of cylinder during run of hand-cranked press
    • Cut paper for work & turn/tumble for small jobs
    • Keep floor mat clear of gripper pedal
    • Fabricate and install hand lever for models without pedal
    • Realign gripper bar, replace bent or stripped screws (NR-221)

    Acknowledgments
    This table was compiled from personal experience, sage advice from my betters and the literature, most of which is listed on the Bibliography page. The following individuals have helped improve this table: John G. Henry, Fritz Klinke, Val Lucas and Bob Oatman.