suckers not picking up the paper

Can anyone help?

I have a Heidelberg T Platen and I was just printing with it and something didn’t quite seem right. Then suddenly the suckers just stopped picking up paper. Now when running the press sometimes it picks up the paper and sometimes not.

Any thoughts?

Thank you in advance,

Meaghan

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OK - my bad! I worked it out. However it does pose a new problem.

It turns out that the suckers were not picking up the paper because is was a hand made stock, so the edges are not completely flat and kind of “wavey” and the suckers don’t seem to like it.

What can I do?

You could always hand feed it on a C&P. The Heidelberg can’t do everything!

Hi Meaghan,
They made rubber suckers that were attached to the regular suckers that made working with cardboard, heavy stock or waving envelopes much easier. Perchance did your press come with any? They seem to be available. Dick

No suckers came with the press :).

Are there different kinds? I have had a quick look in the web and there seems to be a number of different shapes and colours???

Thanks for this I thought it might need some rubber suckers.

You also might try just using two of the suckers turned on. That could allow for less leakage and greater suction at those two points.

In my day +-1960 all were amber latex or black rubber.
Look for 7/8”d w/ 1/8” hole. They come flat and slightly cone shaped. They now seem to come in a variety of colors and thicknesses. Color doesn’t matter. Thinner generally worked easier for me - try 1/32” or less. They are available in 1/16”, but that seems a little thick. They are cheap so having a full selection is probably in order.

Sorry for the two messages, but you might also check the filter for the air system and make certain you have maximum suction in the system.

You are looking for 19H suckers (flat discs actually) from Rudow. Their website is www.suckers.com. They advertise suckers “by the zillions!” These are white rubber so they don’t leave colored scuffs on rough thick paper as it passes under them. They’re around $3 per dozen if I recall correctly. Their number 22 suckers (conical or bell shaped) also fit, but cost somewhat more. I have found the 22s to work well on the Heidelberg Cylinder when the 19s don’t. They don’t seem to work significantly better on the Windmill however. I believe Rudow probably supplies suckers to most of the other places that sell them, so you can either buy through a distributor or straight from them. Have fun with the machine, there’s lots to learn about!

Meaghen -

I havd fed cardboard through my Windmill and have never encountered a paper that would not feed when all the adjustments were made properly. The problem is not likely the paper (although that certainly is a factor), but is likely the settings on the blast and suction being applied to feed system.

Also - run the press slowly and listen for the hiss of air passing through. When the sheet is picked up, the hiss should stop. If you do hear continual hissing, suction is being lost somewhere. As mentioned above, you can turn off the individual suckers that are not needed.

Rubber suckers will help, but the Windmills typically use color-coded plastic bars with different sized holes for different weight papers. You can feed without the plastic bars to get more suction and rubber suckers are worth investing in since they will help to seal the suction during feeding.

Running without the bars - and with individual suction points shut off will give you more suction where you need it. Rubber suckers can be very helpful, but may not even be needed for small card stock.

Plus, the shut-off limit for air being used to create suction is adjustable using the knurled knob to the left of the feed table. Do you have the Windmill Operator’s Manual? It covers the blast and feed adjusments in detail.

The knurled knob with the thin shaft running through it is used to set the automatic shut off. Back off the thin shaft to get the feed working, then lock it in place using the larger knurled knob.

There is also a small lever to the right of the delivery table. This one is used to control the amount of air blast used to push the paper down as it is being delivered. Turn off the blast here and you will get more air where you need it.

Do the same with the powder blast. A lot of air can be bled out of the suction system if all of these other features are being used. Turn off of the powder blast, the delivery blast and maybe even the sheet seperation blast to get more suction.

And, on the pump itself, there are adjustments to control how much air - both blast and suck - is passed into the system. Shutting down some of the suction points will also give you more suction where you need it.

All in all, there are a number of places to adjust suction and blast - as well as the amount of air being pumped through the system. All together, they will give you the blast and suction you need to feed just about anything short of plywood… ;)

Of course, with a hand-fed C&P you will be able to feed just about anything - including thin wood, which I have also done while printing and die-cutting basswood model kits…

- Alan

Meaghan -

As I ran my Windmill last night, I remembered one thing I forgot to mention in my lengthy response yesterday - adjustment of the TILT ANGLE of the sucker bar. This is an important adjustment and may make a difference for you in this case. Look to the left of the feed table for a knurled disk on a shaft with a pointer to ‘thin stock … thick stock”. Try changing the angle of the sucker bar and see if that helps.

Also - that link to http://suckers.com is worth a close look. They sure do have a lot to offer and rubber suckers will work well for heavy stock if none of these adjustments do the trick for you. Just ask for suckers for a 10x15 Heidelberg Windmill…

- Alan

Meaghan -

Heinz Klinke has “#22 Suckers for Heidelberg Windmill, per dozen” at $6/dozen - see http://order.nagraph.com/suckers-grippers-press-parts.html

- Alan

Take a look at the suckers available from Kluge. Primarily for Kluge equipment but have a lot of cross over uses…
http://www.kluge.biz/index.php?page=foil-stamping-embossing-diecutting-c...

I have also found that with handmade papers the edges tend to grab each other making it difficult to seperate

PaulM, See “tab blast” and “comber” features of the feeder here: http://www.kluge.biz/index.php?page=feeder-2

Just one thing, I don’t believe was mentioned. Sometimes the plastic bar may have slid side ways so the holes in the bar doesn’t line up with holes in the suckers. I have trouble with that every so often.

red GTO suckers work Great.

Hi Alan!
Just who are you kidding with this statement?
“Do the same with the powder blast. A lot of air can be bled out of the suction system if all of these other features are being used. Turn off of the powder blast, the delivery blast and maybe even the sheet seperation blast to get more suction.”
The suction is provided by the pump piston moving upwards; the blow is provided by the pump piston moving downwards, both are entirely separate functions.
The coloured sucker slides should only be necessary for very thin stock such as airmail paper.
Don’t try and tell me otherwise, for I operated Heidelbergs platen, cylinder, and offset for over 50 years.

Apologies Alan, my last post is not correct.
What I actually meant to say was that the pump is a duplex one and as the piston oscillates it provides suction from one side of the piston and blast from the other side of the piston. this is changed when the piston stroke is reversed.
The operation is controlled by the action of the feather valves attached to the pump at the base and top.
But I still stick with shutting of the blast has no effect whatsoever on the suction.

Bern is correct that shutting off blow has no effect on suck with this style of pump, but only because the pop off valve lets the unused air escape. On a vane pump closing down blow would be counterproductive to increasing suction as without some place to move the air to the pump loses its ability to take more.
There is a potential spot were vacume can be lost that is very hard to detect. The block that holds those feather valves at the base of the pump has a gasket. It’s a real simple gasket, the last one I fixed I made out of a waxed milk cartoon and it still works 5 years later.
Jeff