Feeding problems on qmdi plus

Hello
Our problem is this when we are running 100# gloss text
the press feeds fine at slower speeds under 6500 sph
When we speed it up it will run 10 to 200 sheets then it will stop feeding
kick off impression, stay running the feeder icon lites up
we have to go to the feeder and push the pile down button just a little and
then it starts again. we have tried alot of diff settings
Any ideas?:

 

It may be air related, the sheets are not separating and it is missing a sheet which is tripping off the feeder. When you run slower there is enough air to keep them sparated to run but not as you speed up. This thread may help on air issues: http://www.colorprintingforum.com/d...ess/problem-suction-blowers-di-plus-2734.html

Also when your press trips off, are you noticing an error on the console that says "DEEP"? If so, there can be some mechanical issues in the feeder pile height mechanism.

Jan or mrheidelberg there is something else that I can't seem to shake out of my memory that causes this and it is something if I remember correctly that is pretty easy to fix. Any ideas?

 

I would say its air related too.....check the pump and its pipes and filters and maybe also the 3/2 way valve.

Regards.

 

Hi Paul,
You know, it could be so many reasons.
To check, your assumption, he should run the paper only instead printing, if then 10.000 is possible it would confirm the separation problem.
If this press used to run well you could look for a single reason of this problem.
If you just start using it, I would check all basic adjustments of feeder to be sure.
Recently I've made service by two different QM DI users, and both presses had their feeder's cam bad
connected to the feeder. In this case you can't reach basic setting as necessary .
And the feeding was very poor up to 6000 maximum.
rgds
Jan

 

I had it too with heavier stock ( from 200 grs ) a couple off years ago, I solved it by connecting a spring at the end of the fane that is giving the pulse to raise the pile or not ( deep low good) since than I can run up to 350 grs paper with no problem at all.

 

I just had the cam replaced on the feeder. I will try a new spring on the feeder height.
Thanks

 

Hi Marc - Could you provide more details on the solution you outlined above - we DESPERATELY need a solution for this issue.

 

Feeder issues

I had the cam follower bearing replaced (because it was broken) that helped a little.When i replaced the spring on the pile height bar,with the new spring from heidelberg,that made all the difference for us. I think both the spring and cam follower bearing did the job.

 

I have heard there is a software modification (or chip) that will double the speed raising the pile, thus eliminating the deep error. I am looking into that. We had Heidelberg come in for this issue 6 months ago. They rebuilt the feeder which helped for about a month. I am a little miffed that they did not include the software upgrade since this is a known issue resulting in the Deep Error. For now, we have added a piece of metal to the sensor which is bringing the pile up faster. Thanks for you information, we will also include your input in our investigation of the problem. I am still interested in what Marc Bremmer did with a spring to fix the problem. I was not exactly sure where he added a spring, and what type of tension. You seemed to understand the process, could you explain what you did with the spring? Thanks again for your input Snappy!

 

I installed the new software (eprom) and all the problems I had with larger enveloppes are solved (deep error). About my spring, I connected it to the piece of metal that passes the sensor for the deep, low good signal. This sensor is situated on the console side, take away the sidecover and you can't miss it. The way I discovered that this was my problem with heavy stock was when I pushed with my finger on the moving part that went down and the problem was gone. I checked this several times and each time I pressed with my finger the problem was gone. In the beginning I connected a postal rubber band to it but this broke after a few months, so I decided to fix it more secure and connected a spring.

 

Rose,

The software fix was optional as the "Deep Error" did not present a safety issue or cause potential damage to the press. The error was very minimal as a problem in the field and could typically be fixed by simple operator adjustments or in exreme instances by having a techncian come out and repair it by set the clearances and timing of the pile hieght mechanism. More often than not these issues were caused with heavy paper due to poor air and vacuum from tired or overheated compressors (This is why heavier stocks run better in the morning before the air compressor gets hot). The software was introduced in 2005 to provide a larger window for the pile to raise and alleviate feeding issues from poor air pressure or mechanical wear in the pile raising mechanism itself.

 

It's not affecting the Pile height bar but the mechanism below it ( the vane that is passing thru the sensor and depending how much it is passing that sensor it is giving the signal deep low or good ) When I first had this problem the pile height light lit up once, the press stops printing but keeps running. To start printing again I had to stop the press first. I discussed this problem ( about 10 years ago with several DI techs from heidelberg overhere but none of them could solve it ( technically the press was ok, so I had to live with it ) I will make a picture of it next week.