Heidelberg 102ZP Perfecting Issue

We are having trouble with nicked or dropped sheets when in perfecting. My operator is running headstops all the way back to stop it from dropping sheets. Checked and double checked the sheet size and everything looks good there. Also when going into straight mode the press will not run when completed. Believe that to be a sensor out. Everything lines up as it should when in straight. Just looking for suggestions before calling in a tech if it is something we may be overlooking and not realizing it.

 

Did you measure the sheet with a millimeter ruler and not what it says on the packaging?

 

My thoughts come from a GTO perfector but i presume the operation is the same:
1. Agree with Not in measuring and putting the EXACT measurement of sheet -if cp2000- or you switch perfector by hand turn machine at the exact spot
2. Also check storage drum is aligned correctly -only in straight mode- there is a special tool that fits in a hole to check it
3. Another thing to check is your suction bar in perfecting -you did not mention grammage of paper if card board you might need to fit rubber suckers- if clogged by dust or some of them are closed

 

We have checked all of those. If you inch paper through it will feed and transfer. Running at speed it will drop sheets on the transfer to the second unit. We are running 50# Offset.

 

Model year? CPTRONIC? Manual, automated or semi-automated changeover?

 

All I can think is to clean the sensor that is located below the press in case it is a 102 zp cp tronic console model 94.

 

Please Not ONLY Clean the sensor.
Be sure, if the1) wires are loose, or broken, or dirty(oil, ink-clean it with spray clean contact cleaner) and
most important if there are
2) +24Vdc, and if
3)see is adjust it correctly.
4) Exchange with other, that you know is Good, and see if is faulty the Sensor, or punt in another placer where
some sensor is working good, and see what is happen.

 

Electronics will have no influence on the ability of the press to transfer sheets.

 

Please think about Mr Mantmann he is saying.
However sometimes if the machine has been getting some trouble in the Perfector system with the sheets, there are
possibilities that Bend Pins in the Transference Tambor .Of course the gear and rack can be faulty.
Check very well the steps that Mr Mantmann suggest.

 

When you say you checked and double checked the sheet size with a finely calibrated metric ruler, did you check successive sheets. I would try checking at least 5 successive sheets to see if they are all the same size gripper to tail. Ive seen variations of up to 3mm on a skid of paper that has been sheeted from multiple rolls. Im thinking that even variations of 2mm would have you experiencing either a knicking, or dropping of the sheet, depending on what size you set up for.
If you do notice a significant variation in size you might want to either send the paper back, or you could try backtriming all the paper to a smaller size if the form allows.