Hello. I have a lovely little SP15 and this is my first mechanical issue I’ve experienced thus far. I hope someone can help me solve it…
Yesterday, my grippers stopped working. In looking at the manual and the press, I see the gripper cams are not lined up with the gripper screws. I am not sure if they are supposed to be, but seems logical those cams push the screws and open the grippers. I also noticed the gripper trip lever looks different than the manual. Perhaps it has fallen? And I’m sure the scrapes next to the trip roller isn’t a good thing. I’ve noticed them before but wasn’t sure how long they’ve been there. I’ve attached some photos.
The pin may be broken. You could also check the linkage inside the motor door. It could be that the spring (X-7522) is broken or that the collar (NR-310) is no longer snug against it. See sheet 189 of the manual.
I’ve tried to get this to work again—I pulled the pin up and decompressed the latch and spring. Any suggestions or ideas as to why it’s not working?
Here’s an illustration from a Universal I manual showing the same mechanism.
The latch and horizontal spring on the front end of the box are probably still compressed.
I pulled the pin up and the grippers are not automatically opening. I still have to use the pedal for them to open, which is fine but I’d like to experiment with this. Any ideas as to why it wouldn’t be working?
The auto grippers are activated by the knurled pin circled in the photo below. When the pin is pulled up the grippers will open automatically just before the carriage returns to the feed board. Then as the carriage is moved further back, the pressure exerted against the bumper springs will cause the grippers to close.
When the auto grippers are activated the operator still has the option to use the pedal
when the carriage is at the feed board or by rolling the carriage slightly forward to open them again. The latter method requires the paper to over hang the feed board to meet the grippers as the carriage returns to the feed board.
If you use the pedal to raise the grippers you may as well as push the pin down. This will make for a quitter printing experience without the unnecessary snapping of the grippers.
The problem was a lot less complicated than I thought. In fact it was simple. I took the gripper bar off and manually pushed the pins. All were working except for the one on the non-operator side. So, it was causing the rod to get stuck. I am assuming this caused the carriage to get stuck toward the end of the bed as well. All is good now and I can get back to work…a big sigh of relief. I know the information you have given will help someone in a similar situation. I appreciate the quick response.
One last question: how would I put the grippers in automatic mode? I’m not sure if I have that feature? I have a gripper bar with only 4 pins, and the manual shows 5.
If there is movement along the linkages from pedal to gripper, where is it failing? Does the wedge push all the way out, striking the ball-bearing wheel on the bottom of the pivoting bar, which pushes in the rod at the center axis of the cylinder, whose cams press the grippers up. If there is motion lost along the way, from loose or worn parts, then you won’t get lift. And if the grippers are siezed from accumulated dirt, no lift, but that wouldn’t come on suddenly.
Another thing to try is to put the grippers into automatic mode and see if there is a difference.
As for the cylinder getting stuck, do you mean it actually sticks in place, or does it hit something and not go past? It is important on this model to always take the cylinder to the end of the bed, even just for inking, and never short-roll.
I will check all of these in detail and give an update this week. I really appreciate the feedback – it is invaluable.
The cams should move with the shaft. If not then they need to be tightened. If this is not the issue then the gripper pins and the holes they slide in may need to be cleaned and lubricated. After cleaning insert the pin and add a small amount of graphite powder to the lower portion before installing the spring and retaining clip.
The carriage becoming stuck at the end of the bed is a separate problem. If the trip spring is not broken, then it may be that one of the white Delrin Trip rollers (X-21119) is missing. There should be four, two at each end. The manual shows one, see sheet 282-A.
Hi Eric – Yes, when I depress the pedal, there is movement along the linkages. The only other clue I have is when I move the carriage down the bed, it gets stuck when it’s supposed to trip. I know the previous owner (3 years ago) had to replace a trip spring, but I’m not experienced enough to know if that would fail within that time or if it is even related.
The cams look right; when they move sideways they should lift the grippers.
Have you been operating with grippers in automatic mode or using the foot pedal? What happens when the pedal is depressed? Any movement along the linkages?