Gto 52 vp perfector

Hi, we have a problem with our gto 52 four colour machine when its in perfect, the 3rd and 4th units wont go into impression, its ok when its in straight print, the problem only arrises in perfect, any of you guys seen this problem before, am i just missing the obvious, it worked ok when we last used it, ive tried changing back and fourth a few times but no joy, any ideas guys, thanks, DAVE UK

 

Not knowing which model for sure be sure the sheet is covering the center suction hole on the perfecting drum if not it will think dropped sheet and will not print. Hope that helps.

 

The impression signal on a GTO comes from the rotary switches on the operator side of the machine. Each unit receives a signal from the previous units switch, once that signal is received, a switch on the unit coming on/off impression is activated putting the unit on impression. So, really 2 switches are needed to come on/off impression, one on the previous unit and one on the unit coming on/off impression. Your 3rd unit will have an additional switch that is only active while in perfect since this unit will be coming on at a different time while in perfecting mode. I would think it is this switch on your 3rd unit. Best way to fix this is just readjust all switches in your 3rd unit, i believe there are 3. To do this inch press until the switch you are going to adjust is at the high point of the cam. Slip a 1mm gauge between the wheel and cam and loosen the switch, then push the switch up to the cam and retighten the switch. Double check your setting by removing the 1mm gauge and making sure you can lift the wheel off the cam just slightly. Repeat this process on all switches on this unit. This should do the trick unless one of the switches is bad.