Challenge MEDALIST 820, Instructions And Parts Manual

Page: 14 / 80

F.669-D/820-870/Jan 98
14
Air Blast
Openings
Separator
Guide Lock
Set Screw
3. Turn the speed control to 1/2 or full speed. Place
your thumb on the back of the lift to keep paper from
feeding. Press the green rocker switch, the sucker
wheel will start to turn. Reduce the pressure of your
thumb to feed only 3 to 4 sheets. Press your thumb
down to stop the feeding again. Press the red rocker
switch to stop the sucker wheel from turning. If the paper
did not feed, adjust the position of the vacuum advance
(fig. 20, pg 13), bleeder valve (fig. 23), or sheet sepa-
rator, (fig. 19, pg 12).
4. Check the accuracy of the 3 or 4 sheets fed. It may
be necessary to adjust the fold stop, (fig. 24), or the
squareness of the fold stop, (fig. 25, pg 15), or the
squareness of the side guides. Try only one adjust-
ment at a time then repeat step 3.
5. If the folds look good, the job may now be run. The
speed of the folder will affect the accuracy of the folds.
Folds set up at slow speed will be different at high speed
and will need to be fine tuned.
Note: All of the controls mentioned above contribute to
smooth and accurate folding. There are many combi-
nations possible depending on the condition of the pa-
per and environment.
(fig. 22)
Bleeder Valve
(fig. 23)
Fold Plates
Plate set up will depend on the type of stock and type
of fold you require. The fold plate design on the Med-
alist allows changing from open or closed deflector
(up and/or down folds) without removing or turning
the plates.
(ill. 3)
A good understanding of the roller/plate configuration
will help you decide which plate to open or close for up
or down folds. Illustration 3 shows the paper path for a
common Z-fold.
A self adhesive folding guide label is included with the
manual and may be conveniently placed on the deliv-
ery tray. Used along with scales on the fold plates, the
guide will help you quickly establish a rough set up for
some of the most common folding jobs.
Inch/mm
Scale
Quick Setup
Scales (read at
these points)
Plate Stop
Coarse adjustments are made by loosening the lock
screws on the plate stops, (fig. 24), then moving the
stop. The plate stop lines up with the scale marks along
its front edge (not where the paper contacts the stop).
Fine adjustments are made with the micro adjust knobs
on the ends of the fold plates, (fig. 25, pg 15).
(fig. 24)
There is a bleeder valve on the vacuum pump, (fig.
23), which allows for vacuum adjustment from com-
pletely off to completely on. General settings for the
bleeder valve are half open for 20# stock, and closed
for 80# and heavier stock. If your machine is feeding
doubles, this can be opened slightly to “relieve” some
of the vacuum and stop the double feeding.
Bleeder Valve (Vacuum Adjustment)