GTO 46 Gripper bar noise

Good day have a GTO 46 and I am getting and suddenly i am getting a knocking sound from the Transfer Gripper bar area. #1 I don't know how to take out the gripper bar. and i can only assume that to find out the solution that needs to be done; can't say for sure.

The the machine was working fine for years; and this problem didn't occur during operation; we ran the press all day tuesday of last week; shut the press down; and when we started the press up on wed. morning the knocking started. It's a slight knocking sound when the gripper moves in position to collect paper. any assistance in this would be greatly appreciated.

 

I wouldnt suggest taking out the swing gripper if you have never done it before. Kinda tricky getting it back in correctly. A few things to check, first of all I am assuming this is a single color. The noise can really only be coming from two area. First area to check are the 2 points that the swing gripper rests against when taking the sheet off the feed board. Use two thin sheets of paper and make sure the gripper bar is coming to rest on these two points at the same time. You will need to have someone turn the press by hand while another is under the feed board positioning these sheet of paper between the points and the swing gripper. It is not uncommon for these points, which are actually set screws, to come loose or break off. The second spot to check is where the cam follower touches the "moveable" cam. Again, under the feed board on the drive side you will see what looks like a curved cam or banana cam. As the swing gripper comes back tword the feed board the cam follower should smoothly go onto the banana cam. There is a long rod with a lock nut on either end of it which controls the position of this cam. Sometimes these lock nuts can come loose and get the cam out of position. It is also possible that your cam follower is bad. If you have a multi color there is a whole list of other issues you can have.

 

exheidmech its a single color so i will try out the suggestions and get back to you; thanks for your assistance

 

hey reply to the items to check; we checked the 2 points that the swing gripper rest against and they were a little slack; we tightenend them and the knocking sound is still there; we checked where the cam follower touches the moveable cam; and the and don't see anything that is abnormal; we have checked this whiles turning the handle slowly but can't seem to see what could be causing this knocking; any more assistace would be greatly appreciated thanks again for you first reply

 

Could also be a broken torsion rod. Take off the operator side cover and you will see what looks like a bicycle chain. You will need to remove the clamp that the chain is attached to, make sure you mark it before you remove it. Three 5mm allen bolts will hold in a collar. Remove the allens and the collar will slip out. You will then be able to pull out the torsion rod which is actually a large diameter wire maybe 5mm in diameter which is kind of "U" shaped. This will also slip out. Make sure this is in good condition. If this is ok I would think the swing gripper is ok. Maybe look at the had stops, or the traveling feed board grippers maybe causing the noise. Take off the drive side side cover and see if you can find something that doesnt look right.

 

ok thanks exheidmech; i am in the Bahamas and it's 1:17 am now so i will work on this first thing in the morning and report back; thanks again. any luck on the service manual for the gto52?

 

also what is the had stops? and it might take a lil while to take off that side; we had it opened once before and we had to use a special tool to take that panel off with the motor being on that side.

 

Sorry about the misspelling, i meant head stops.

 

exheidmech; we finally got it; upon opening the side panel we realized that the special v belt had quite a bit of grease and oil on it; we took the belt down and dried it a bit and attached it and the press runs fine without the knocking; what had happen was that the greasing and oiling of the parts every few weeks and the oil had built up and dripped on the belt and was causing the gripper to slip; and there was the noise; thanks again for you help; really appreciated and saved us thousands of dollars ps. still hoping to find a copy of the service manual gto52 even if we have to pay; thanks again.