GTOZ dropping sheets and misregister

Hello, I am faced with a strange problem on GTO 2-colour. After printing large stock, like over 250gsm, it becomes problematic to print smaller stock like 130gsm. The sheets drop under the machine after transfer drum between the 2 units. The second unit also does not register. The machine is a perfector but used on straight. Please help!

 

HELLO SIR..IT SOUNDS TO ME LIKE YOUR PERFECTOR GRIPPERS COULD BE STICKY(LAZY) OR NEED SETTING BUT ALSO CHECK IF THE TIPS ON THE PINCER BAR ARE OK AND ALSO THE CAM-FOLLOWERS WHICH CONTROL THE PINCER BAR MOVEMENT..THE THICKER STOCK WILL POSSIBLY HOLD BETTER.ONCE YOU RUN THIN STOCK IT IS HIGHLIGHTING THE PROBLEM AS THE PAPER IS THINNER AND NOT GRIPPING PROPERLY..
IF THE PINCER TIPS ARE FINE(WITH RUBBER ON) AND CAM-FOLLOWERS OK IT SHOULD ONLY NEED SETTING UP PROPERLY..THIS CAN ONLY BE DONE IN PERFECTING MODE WITH THE CORRECT SETTINGS AND EQUIPMENT..REGARDS.. pressfixt@gmail.com

 

Thanks MRFIXIT for your response. Checked the machine today again. You are right, the thicker stock holds quite well. The grippers could be be sticky as you say. The pincer gripper tips look ok, there is rubber on. One question though, how do you check that the cam foller is Ok? And can setting be done above the machine at the point when the pincer grippers are open? What is the procedure? Any special equipment needed for this setting?

 

HELLO SIR..I WOULD UNSEIZE ALL THE SPRING LOADED TIPS WITH WD40 SPRAY OIL SO THAT THEY RETURN UNDER THEIR OWN STEAM..
THE CAM FOLLOWERS CAN BE CHECKED BY SQUEEZE THE PINCER GRIPPERS CLOSED(PUSH THE FIXED GRIPPERS TOWARDS THE RUBBER TIPS AND CHECK THEIR BEARING.. THEN CLOSE THE SPRING TIPS ONTO THE FIXED GRIPPER TIPS BY MOVING THE OUTER TUBE TO LIFT THE OTHER BEARING OFF THE CAM)..EACH BEARING SHOULD BE SMOOTH TO TURN WITH NO WOBBLE OR PLAY..
AS FOR SETTING THE GRIPPERS..YOU NEED THE SERVICE MANUAL,DEGREE-TIMING WHEEL,POINTER AND ZERO POINT GAUGE TO SET THEM TO THE CORRECT OPENING/CLOSING TIMES...THE DEGREE-WHEEL IS USED ON MANY PRESSES eg- K-LINE, GTO, MO, SOR-LINE, SM72/102..THE NEWER CPTRONIC PRESSES HAVE PRESS DEGREES DISPLAYED ON THE CONTROL PANELS..
THE MACHINE NEEDS TO BE IN PERFECTING AS THE ADJUSTING SCREWS FOR THE PINCER BAR ARE ONLY ACCESSABLE PROPERLY AT THE TIME OF CLOSING AT THE SUCKER BAR..THE EASIEST WAY FOR ONE PERSON TO DO IT IS TO ATTACH STRIPS OF THIN PAPER WITH A HEAVY BALL BEARING/WEIGHT TAPED TO THE END AND INSERT THE PAPER FROM BELOW WHEN THE TIPS ARE CLOSED..YOU THEN SLOWLY WIND THE PRESS BACK TO THE CORRECT CLOSING/OPENING POINT AND ADJUST THEM UNTIL THEY RELEASE(YOU WILL HEAR THEM DROP ONTO THE BASE)..THE TOLERENCE FOR ALL THE GRIPPERS IN THE PRESS IS + or - 1 degree ..WHICH IS VERY FINE BETWEEN EACH SET OPENING/CLOSING... IF YOU NEED FURTHER HELP CONTACT pressfixt@gmail.com

 

Great MRFIXIT, you can really fix it!. Just as you advised, I unseized all the spring loaded grippers with WD40. They are now free. I also checked the cam followers and seems like they are quite OK.
I managed to set the grippers but without the degree wheel and zero gauge. We have no luxury of some of these special tools down here. The whole process was by trial and error and it too the whole day, with tests and pulling a few sheets after every adjustment but we made it, the machine now is able to pass paper smoothly all the way to delivery table without dropping even a single sheet. The only draw back now is a very slight occasional mis-register, random after several sheets, but tis is acceptable for us. All in all, machine is back in production and everyone is smiling now.
Thanks a great deal MRFIXIT. Will definitely get in touch incase I need further assistance.

 

Hello..i am happy you made some improvements.even with the timing kit it is a fiddly time consuming job especially if doing it on your own!!! .but desperate times mean desperate measures if you need to do an emergency repair...to get the register perfect now, will need the timing to be 100%..this would only be possible with timing kit and settings..the main thin for you is to get all the tips working together at the same time..the ones that were gripping originally were probably the ones to use as a reference point to set the rest that were not working..i am happy to help where possible..thanks..