Cam Follower replacement....

I have an sm52 4 colour press, the problem started last week when i was getting a small tear in the grip edge whilst printing 520x370 size 300gm board, realised it was every third sheet so inched round and located which gripper was at fault.
Removed last gripper arm just to finish job everything was ok.
Later it started doing the same on sra3 stock so replaced the outer gripper arm and removed the next one in from end.....
Finished all the important work so had time to clean and have a good look, seems to be the bearing on the cam follower has some play in it, you can hear a faint click when it opens from the cylinder and then when it drops....also if i print flimsy stock then the drop is flicking every third sheet so i have had to adjust everything and run it slower, not what the boss likes....

Sooooooo....after all that, i need to know is it just a case of tapping out the pin of the cam follower swapping bearing for new one and replacing.
I dont want to call out engineer for something i can do as its 200 mile round trip for him.

 

Its strange that you say its every third sheet, there are no cylinders in an SM52 that would produce a every third sheet issue. Which cylinder is the suspect cylinder? If you just want to replace the cam follower, this can typically be done in just a few minutes with the proper tools. On the gripper bar itself you will find 1 collar that has an internally threaded hole in it. This collar is used to jack up the cam follower off the cam by using a long 8mm bolt. Once the cam follower is off the cam, loosed the 4mm bolt holding it within the cam lever. Inch the machine into a position where you can push the cam follower out and install new cam follower. Typically you will also want to readjust the grippers when a new cam follower is installed.

 

Sorry forgot to put that its the delivery grippers, so every third sheet means one of them is out of allignment, all i could figure myself was that the cam bearing has more play than the other 2.
To look at it seems just knocking the pin out and remove the cam arm.
I normally have alan from rooney and mills sort out my press but this looks to simple for me to pass up.......although having never set grippers i may be out of my depth.

 

Ok, got it, I am guessing you have a low pile delivery than. The easiest way to change a cam follower in a delivery gripper is to remove the gripper bar. Loosen the clamp that holds the cam follower in the gripper bar. You will likely have to tap the cam follower out fo the clamp and tap the new cam follower into the clamp. If you look closely, its actually an eccentric bushing that the cam follower is tapped into. This bushing is what is clamped into the gripper bar lever. If you look really close at the bushing, it will have a hex shape to it so you can turn it. Look at each tip of the 6 points on the hex. 1 tip you will find is actually flat and not pointed. This flat tip needs to be positioned so it is facing the bolt that clamps the cam follower in the lever. There is a split in the lever that the bolt goes through, i usually will position this flattened tip at the split in the lever. Once this is done tighten the bolt. Adjusting the grippers is not easy if not impossible to do accurately without a jig on any SM52. If you still have a gripper that nicks the sheet, just try adjusting that gripper a bit.

 

Cheers for the advice, i think a call to my engineer will be on the cards.......i have the skill to do the job but since getting my hand smashed in a gto i havent got the hand strength to carry out this repair....

 

Its actually a pretty simple repair but gettting it done accuratly and having all the gripper bars set exactly the same is very important especially at high speeds. It should be noted that the jig needed to set the gripper bars is not even available from Heidelberg for whatever reason. However, in their manual it does show the specs needed to have this jig machined. I had to have one made years ago and still have it. Maybe now it is available, who knows. Good luck

 

Well said exheidmech, you know your trade.

 

hello sir exheidelberg can you please help me on how to replaced the cam follower and tapered pin of swing gripper sm 74 machine because the gripper tips is touch in the cylinder during transfer of papper.I adjust the swing gripper but not succes.thanks