Problem with Polar 72 cutting machine

[marantvou]

Hello to everyone.

This is my first post to this site and I wish good health to everyone in the world first of all.
I have some problems too like everyone.

I have an old Polar 72 Eltromat cutting machine (manufacturing year 1980) and on winter it works okay but in the summer when the temperature gets high it doesn't work. I push the cutting buttons and the knife doesn't come down to cut.
What might happens ?

Many thanks to everyone that can helps.

 

[Al Ferrari]

Does everything else work?
Does the main motor spin up?
Does the back gauge move forward and backwards?

If you answer yes to the above, then my guess is that there is a micro crack in some trace on the control board, or some defect in the cut push buttons themselves.

Get a service man in to check it out.

Al

 

[marantvou]

Al , thank you first of all for your reply.

Yes everything else work. I will check the two other reasons you wrote with a technician of our area because the official service here says that they don't service these old machines any more .

Thanks again

 

[dabob]

We used to have an old eltromat and as I recall there was a mechanical clutch that as it got warmer it didn't want to work and the warmer it got the less it liked it - we sold it but I would look into that clutch assembly first . . . .

 

[marantvou]

Thanks for your reply too dabob,

I will look at this clutch assembly.

Thanks again.

 

[Buntpapier]

If a mechanical clutch does not work in relation to the temperature the valves inside the hydraulics getting older.

But the clutch in a 72 is electrical!

"Everything works" is a relatively good answer. If you push the cut button the machine does a light barrier test. If you do not have a light barrier (this was not required 100 years ago) the clamp is going done.
If the clamp is moving the switch for “clamp in upper position” will be released and after a short time the clutch will be activated.
My first question would be – is the clamp moving?

Buntpapier

 

[marantvou]

Hello Buntpapier.

Yes the clamp is moving but the knife doesn't come down.

Thank you for your replay.

 

[Buntpapier]

Hi Marantvou!
Does the machine has programming or is it a Standard?
If it is a Eltromat it should have magnetic tapes for programming.
The next step would be the correct machine number to get the right electrical drawings. Do you have the drawings? If not, send me a Email address to me account here in the forum.
As well you need an electrician which is able to read the drawings and is able to measure the individual signals.
Meanwhile you can check the carbon brushes at the fly wheel. You switch the machine off (!), open the flywheel cover on the right side and check the conditions of the carbon brushes. They should run correct on the two rings. The springs should have a bit tension to get contact. I clean the rings with fine sand paper (320 - 400). If you clean the rings and the motor is running, you should work very carefully! I don't like to read the report of the next hospital here in the forum.

Buntpapier

 

[marantvou]

Hi Buntpapier
The machine has programming but i don't know if it has magnetic tapes. I will look for the drawings and I will inform you. I will also check in the meanwhile the carbon brushes and clean the rings. Do you think that might be an electronic problem and not a mechanical clutch problem as member dabob mentioned a few days ago ? Or the electronic check is a routine check ?
Thank you.
Marantvou

 

[Buntpapier]

Hi Marantcou
The 72 has no hydraulic clutch like the other Polar machines. A mechanical clutch problem would have a totally different reaction. But we will see.
The electronical step will come up anyway. But before your ask a local electrician for help we should prepare eversthing for him. Otherways he does not know how the machine works and you spend money for nothing.
Don't forget, we need the machine number, to get the correct drawings.
Buntpapier

 

[Krojcer]

Hi Marantcou
have you fixed this problem?

I have totally same problem, but with Polar 76SD, with electronic cards, with no programs.
When it's cold there isn't any problems, but starting from may it makes 10-20 cuts, and shows error code 86. When I turn it of, and on after 5 min. same thing happens.

Any help?

 

[HPC]

Check the air gap on your clutch.. I think it should be .010 when off and .010 on (you will need to manually engage the clutch to check the other. If your air gap is too big it will slip and heat up. Shim with plate material or metal.. do not use plastic. Also, check your brushes make sure they are in good shape. I am not a tech but I've fixed our 76EM and our 72.

 

[Buntpapier]

Check the air gap on your clutch.. I think it should be .010 when off and .010 on (you will need to manually engage the clutch to check the other. If your air gap is too big it will slip and heat up. Shim with plate material or metal.. do not use plastic. Also, check your brushes make sure they are in good shape. I am not a tech but I've fixed our 76EM and our 72.

And make sure you have enough money on the bank! If the clutch does not open after the next cut you need a new cutter.

 

[Buntpapier]

Hi Kojcer
You need either a clutch revision at the gearbox or / and a new electronic board. The clutch revision should be dome somebody who knows Polar cutters. Nothing you can do. Could be an independent former Heidelberg specialist from Prag help full? If yes send me a Mail.
Buntpapier

 

[marantvou]

Hi Krojcer

I am sorry. I haven't fix that problem. I understood that it doesn't worth it because it started happening at days that are not too hot like now on Spring.
The Polar is very old (80's I think) and it might be better buying a used one either fix it.

 

[Krojcer]

I have got some diagrams from him, so I'm waiting for electrician to check everything

 

[quadraernie]

the brush can be dirty or bad-adjustment o need replacement.
However you must test the relay d21a-b, clean and adjust them.
You must need to test the right voltage with the VOM +42Vdc to the brush.
Need the wiring digram. reach me
[email protected]
quadraernie