Polar 76em cutting out about half way through the up cut decimal point flashing

Hi Guys, I have what I believe to be a 1988 Polar 76em (serial number 6061675) that is cutting out about a quarter to half way through the up cut, whereby the machine just freezes and the decimal point flashing continuously on screen . I then have to turn the machine off wind the blade manually to the centre position to enable me to turn the machine on again,when I turn the machine on I believe the error code that i get a split second glimpse of is '88' .It has happened intermittently in the past but is now happening on every cut, Any help or advice would be much appreciated!!!

 

Hi,
Your machine made in 1990. Not 1988.
You have a problem with so called "safety bolt". It seems the safety bolt has a mechanical stiffness and won't return to it's resting position within the timeframe.

The safety bolt is a solenoid which mounted on the right side of the back side of the machine frame. Go back side of the machine and remove the cover of it. There are 2 sensors monitoring it's two positions. The closest one to the machine frame is monitoring the resting position and the other the retracted position. When you trigger a cut, the solenoid should quickly retract (should be within 2 seconds) and the position should be acknowledged by the sensor). And when in the halfway of the upstroke, it should return within 2 seconds. Due to a mechanical stiffness, it might delay a bit to return.

Pull the solenoid by hand and pour some oil on to the shaft. If it didn't help out, you have to remove the 4 bolts and pull the whole solenoid assembly out and pour oil to the big steel pin and bore on the machine frame.

Hope this helps.

 

Hi NimeshSilva,thanks for you courteous and informative reply. I am a bit lost in regard to the instructions (my fault not yours).I am pretty sure i have the located the area you speak of as i have to access this area to wind the fly wheel round to find the knifes centre position to enable me to switch the machine back on.I have oiled the solenoid you speak of but am unsure of the four bolts i need to remove the assembly,I can only locate three small 5mm allan bolts that when I remove will only loosen the assembly but not remove it which doesn't allow me to oil the big steel pin as i believe stiffness is the problem.I have attached a couple of pics in the hope they may explain my confusion,Thanks Mac

 

The photo shows the gearbox and the cam switches. Just above this assembly you will find the safety bolt and the 2 sensors.

But there is a newer design which the safety bolt comes inside the machine frame. In that case, you have to remove the plastic band from the flywheel side which covers the machine frame. Inside it, you will find the safety bolt and 2 sensors. But, if that's the case, there is no big steel pin, instead, you will find an arm which locks the knife career.

Some photos of this area might help me to identify which design is yours.

 

Hi Nimeshsilva,please find additional photos hopefully this will give you an idea of where i need to go next,thanks for your advice and patience with this!! Regards Aaron

 

That's right, the 2nd photo shows it. Your machine belongs to the newer design. Lubricate the hinge of that arm. Check the arm movement and you might find the problem.

And about those sensors, the steel plate in front of the sensors should be around 1mm max away from the sensor. If the gap is too much, it will not acknowledge the position of the arm. Sometimes there might be an LED on the sensor, so that you can see the sensor is working or not. If the sensors not sensing the steel plate, try adjusting the gap. And also look for any horizontal "play" of the arm too.

Hope this helps.

 

Hi NimeshSilva thanks again for your help with this, I have sprayed around the hinge with oil (when you say hinge you mean the block with the steel plate attached that hinges on what seems like the circular pin in the middle of the picture??) and checked the sensor distance which is fine in as much when I push the steel plate downwards a small red led flashes on the bottom sensor,however when i try to cut anything the problems still persists and the blades stops on the up-cut,any ideas??
Thanks Aaron

 

Check the LED of the top sensor too. The arm should start to fall at Tad middle of the blade career travel. The timing is critical here..

 

Hi, I have attached another photo to show you where the steel plate rests when the blade is fully up the top of the top sensor that has no led is almost level with the edge of the plate,does this help??

 

Try apply a little downward pressure on the arm by hand as somebody triggers the cut. As the blade start to come up, press harder the arm. Then it should come down little bit ahead of time. See whether your problem go away. If the blades returns with no 88 error, then the arm is sticking at the retracted position.

Please do it very carefully as the moving parts can injure you.

 

Hi NimeshSilva,hope you are well,thanks for your help thus far, I have tried what you have suggested with little success.I have used a small piece of wood to enable me to push the arm down as the cut is triggered but the problems persists as the blade retracts although I can sometimes get one or two cuts before it does so,any further ideas??

 

Hi,
If you got at least one successful cut by following my method, it is confirmed that you have the problem with the safety bolt timing. Have to Check further, but I need to be physically there to have them checked. It's very hard to give you instructions from this point. I'm really sorry about that.

But you have to check the safety bolt timing thoroughly. And the cam switch contacts as well. And also check the two sensors as well. Because sometimes the sensors may have some delay turning off..

Hope this helps

 

hi sir,
am attuned the same cutting machine polar 115EMC, and the same problem in knife down position stopped. am checked proximity sensor and gam switch but good condition, am doubt the hetrolic pressure. further any idea sir?
need help sir

 

Hi sir
Good day, i hope you are well
Maybe i can help you and guide you to fix it
if you send me the details Resume of problem to my email

 

Maybe if you send me email with all explanation, i can guide you
and fix it.
Remember Polar is combination de 4 systeme: 1) Electrical 2) Electronic 3) Mechanical 4) Hydraulic
all them are very precisely and syncronized. And get the Schematic and Wiring Diagrams for fix it.
Of course little knowledge of Electrical,electronic, mechanica, and hydraulic, BUT most important thing
the best Tool is : Common Sense!

 

Hello. Im sorry im interupt. But can anybody give a picture or photo of "safety bolt"? And where is its position in the machine. Thanks a lot.

 

Hi sir
Where is located "Safety bolt"

 

There is no box above gearbox in our machine

 

ok sorry by my delay.
Now you must adjust the paper cutter, with Plastic cam lever, and limit switch
you must do it, by proof and error. Since your paper has NOT Safety Bolt Solenoid.
Remember the Knife must be there in Hight point Top.
However try to clean the limit switch of gear board or cam lever, by dust or loose wires, or break wires, or contact dirty or defective.

 

Hello. Sorry, I'm interrupting. But can anyone give a photo of the "security screw"?
And where is its position on the machine? Thank you very much.