feeder problems

i am having major problems. it satrted a few days ago with the late sheet symbol coming up, so i advansed the timing, this kept going until the timing was on 5+. now it will run only for about 50 sheets then cut out with the late sheet sybmol coming up???? has anyone had this b4??? i can increase the suction to 10 on 150gsm and problem still happens which seems strange, have cleaned and greased grippers, cylinders, wheels, clean filters on vac pump, adjusted wheels on cams... not sure were to go from here... sometimes it runs for more than 50 then comes up with a feeder problem symbol...how does the machine detect if the paper is late? as i thought the VD dector might be invloved but, i can turn that off and the prob still happens.

please help... i am pulling my hair out.

 

Is this machine a Classic, Plus or Pro?

 

tuning in

got the exact same problem with my Plus.

 

I have had this same problem on our press and a simple cleaning can possibly take care of this...
If you open the door on the drive side as if you were to get to your black plate wash-up device. If your looking at the press with the door open, its on the bottom left hand side, Their is a silver box about the size of a deck of cards. It has 2 hoses going into it, one into the top and one out the bottom. There is also a pin that sticks out to the right that you cant see since it is behind part of the feeding cams (but take note where the pin is - b/c it will need to go back in the exact same spot, it rides on a cam.) It should also have 2 allen head bolts on it.
If you take this silver box apart it will most likely be full of powder, what i've noticed happens, is that it doesn't let that pin push in and out smoothly and this plays a part of how your pile rises consistently.
When you clean it, it does have a loaded spring on the inside of it so be a little careful that your not staring at it when you take the last screw out. Just clean it out really well, take the rubber gaskets out, and just put a little oil on your finger and smear it on the inside of everything so it gets rid of the friction.
When you go to put this part back on the press, if its to tight of a fit, close the door and inch the press around until the cam is in a further away position. That pin actually sits on a round cam and its kind of a pain to aline the pin on top of the cam. Once you do it one time and understand the way it works, it should only take about 10 mins to take off, clean and put back on the press.
Let me know if this helps any, or if you need a few more details on the how-to part.

 

classic

 

tuning in? what is the proceedure for this?

 

cheers mate, will clean this morning..

 

Turning off the VD sensor stops it from reading doubles, it still measures sheet length and arrival timing. I would however clean the sensor as it is prone to getting paper dust on it which can cause erroneous sheet arrival readings.

As for pulling apart the 3/2 valve and cleaning it, I urge you to take on this task with careful consideration. It is possible this item could be contributing to your problem but also may not be. Most people are not aware this box when moved can alter the timing up to 15 degrees as to when sheets are supposed to be picked up from the pile. If you do plan to take it apart DO NOT loosen the (2) 4mm allens which hold it in place as they have been set at the factory. Only remove the (4) Phillips screws to take the cap off. When removing the nylon 3/2 valve be sure to remember which way the nut on it was facing so you put it back in the same way. If you put it back in backwards you can bend the operation shaft or break the bearing the shaft is driven by.

Also do not lube the o-rings with any petroleum based lubricants before installing the 3/2 valve. It will cause the o-rings to swell and hinder the operation of the valve. The best thing to use is a dry lubrcant like graphite or a light coat of lithium grease which is recommended by the factory.

I would recommend looking at the cam followers on this side of the press as well as the pile height mechanism. If any of these are worn it could also contribute to poor feeding.

I hope this helps...

 

Paul,

Im just curious about this with my press then, I've working this press for about a year and a half now, and worked with a classic for 5 years prior to this. The classic never had this problem, but now with the plus im working with, it seems to be a reacurring problem. I have honestly taken it off and cleaned it 3 times now, where with the classic, never once had to touch it. (Let alone knew it existed) Whenever we do run into (similar) problems this seems to be the answer. What would make this a reacurring problem with our plus model?
Also, with the 2 allens that hold it on, it seems like it only has one place to go, just wondering how the 15 degrees can run out when it has always seemed like it only fits one way, my guess is the bearing that the pin rests against can be off?
this is all great info for me on this! thanks in advance!

 

Dutchb,

The way that part is set at the factory a digital vacuum guage is attached to the vacuum line and the press is moved to a certain degree (Can't tell you which one or I would have to...). Next the 3/2 valve is moved back and forth on the those two 4 mm allens until a reading of -30 millibars is read on the guage then the allens are locked down.

Amazingly, the window of movement, as little as it seems to you, can be as far as 15 degrees off the target degree it should be at.

My guess if you are having reoccuring problems with the 3/2 valve is that the o-rings on it are swollen and causing it to bind when it starts to get hot. If you have been using petroleum based oil when cleaning it I am sure that is the case. Also keep in mind oil will trap powder and paper dust not allowing it to move through the 3/2 valve as it would if you were using a dry lubrication.

Another thing to keep in mind is the pump for the feeder gets extremely hot during operation. If your feed problems are happening in the latter parts of the day it could be because the hoses from the pump it self have pinched closed, when the air lines are cool a bend stays a bend, but when they are hot a bend becomes a crease restricting air flow. In a vacuum they sometimes collapse. The clear one right on top of the pump was a prime candidate for this.

If you look back at some of the other forum topics concerning feedeing issues I have written about a few other issues to look for in great detail.

 

Hi Paul,

i have found a cracked pipe at the top of the 3/2 valve. i repaired but still the same problem( could this have sucked some powder or something down into the valve as this line looks to come from the suckers??)), have cleaned the vac pump veins, still have a problem,, as about 50 to 100 sheets its says i have a late sheet. what acutally tells the machine that it has a late sheet?

 

paul , also it looks impossible to dimantale the 3/2 valve without undoing the 2 hex bolts as the 4 star screws are not ecessable??

 

i have slowed the machine right down and just letting it feed, i watch the 3/2 valve and it operates no problem, when the machine faults with the late sheet it is in the grippers??? to me there is no reason for this. is there a sensor that tells the machine that it is late? how does the machine detected this. to me the 3/2 valve controls the suction to feed the paper into the forward rollers?

 

ok, i beleive it is a electrical problem, any ideas?

 

nope not electrical, i am lost, does the 3/2 valve have anything to do with the pile rising? after cleaning and reseating x4 and vd senor and conectors i can now get around 300 sheets b4 its either goes into pile height problems or has a late sheet.

 

disengage the temporary sheet monitoring by calling the special function "18", turn it "OFF", it will not monitor the sheet travel for the job you are running and come back on with the next one.
Hope this helps.

 

have already tried this and it still late sheets..

 

cleaned the 3/s valve out and reset.... still late sheeting,,,,,realy lost now..

 

well my mine is spinning, now i'm thinking that it might be the VD sheet senors as thats all it can be????? even though i turned off sf18 and sf19...whats everyones thoughts? the cams don't look worn to me??

 

what happens when you adjust your timing control ?