The Book Arts Program at the J. Willard Marriott Library, The University of Utah has a Vandercook 15-21 (shown with the top frame assembly removed) that is experiencing difficulties. Within minutes of application, a majority of the ink added migrates to the non-operator side (highlighted in the image) of the ink distributor assembly and form rollers
Any suggestions for correction are much appreciated.
Does the 15-21 have a skew adjustment like the #4? I haven’t had much time to look at this model. I recently had to adjust the skew plates on a friend’s #4. They were so far out of whack that the front roller and rider weren’t even turning. To be honest this is the first skew plate adjustment I have ever had to make.
The Arm Letterpress
What I should have said is: make sure the rider rollers are parallel with the form rollers–that’s what the skew adjustment is for. If the riders have out-of-contact areas with the forms, the skew adjustment should be tried. A twisted frame however will need straightening.
Assuming the rollers are set perfectly parallel to the bed, the quick test for levelness of the ink drum would be a jerk-stripe. After distributing the ink, let the rollers come to a stop and sit for 15 or 30 seconds, then lift the rollers out of contact. Advance the carriage and read the stripe on the ink drum. It should have the same thickness from end to end. (It’ll be thicker than the stripe on the roller setting gauge.)
You should also make sure that form rollers are parallel to the ink drum–there’s an adjustment to skew them by shifting the plates that contact the ends of the cross-rods, at least on the #4, and it looks similar in the photo here.
The steel tie rods could be slightly bent. I believe that the frame ends on the 15-21 are steel, and not likely to be warped. However, if brass like on the No.4 the can be pounded flat with a rubber mallet.
Perhaps, the problem is not with the bottom frame, but a twisted top frame, which like the bottom frame is freely removed from the press.
The only other thing I can think of at the moment is that the ink drum is not level, but I would guess this would be obvious.
Thanks for the suggestions, Paul. The form rollers have been adjusted correctly and the lock screw (MR-134) properly tightened.
Dave Seat was here recently and suggested the top frame might be bent, but the problem persists after he gave it a tweak.
We have access to a machine shop (they have made some parts for a couple of our presses) but I’m unsure how to communicate our needs as I’m uncertain what needs to be corrected. Any additional suggestions welcome.
This is most likely caused by neglecting to tighten the lock screw (MR-134) on the bottom frame assembly. (See Sheet 179 of the operator’s manual.) Vibration from the ink reservoir drum causes the adjusting screws to turn counter clockwise thus lowering the rollers on that side of the press. Also check the threads of r the adjusting screws. This is applicable to the No.4 and 219 as well.
Another cause could be a twisted frame due to it having been dropped on the floor. This may take some machining to correct.