Bending the paper stack on a windmill?

Hi Folks, For quite some time now we have struggled with our Windmill every few prints throwing off and printing on a slight angle. We have tried everything under the sun - gauge pins, packing, impression strength, cleaning grippers and have spent quite a deal of time just trying to figure out what on earth causes this issue. We have also had a retired letterpress master helping us, however he too has been stumped.

This afternoon, after much of a frustrating day having this issue arise today, I decided to turn my attention to my paper stack. Printing on 300gsm lettra we were printing from a brand new ream of paper. We always fan the stack prior to printing, and give it a little bend to loosen it up. However today I decided to give the stack an almighty downward bend and run it through the press. Our occurrence of misprints was drastically improved. Not perfect, but a far far improvement.

So my question is: How much do you bend your stack of lettra? Could this be the cause of all our issues?

Would love to know your thoughts??

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Are you running commercial or are you using the guides?

Im using guide pins fastened out of paperclips (the poor mans way) if thats what you mean?

Paperclips work just fine and they are cheaper too. If you stand on the side of the press while it is running you should see the problem. It’s either jumping the pin/drop guide or getting knocked out of register. I curl, decurl, work my paper which ever way the press wants it. When you curled your paper it probably helped to keep the paper in the bottom left guide instead of jumping it. If your paper clip is not bent correctly, sometimes it will hit the paper and push it out of register. Also your paper could be slidding under the drop guide…then an upcurl is good. Hope this helps.

Thankyou! We have spent a great deal of time watching the press print from the side. It always looks like it is fine and isnt missing the guides.

Does it seem like a possible answer that we always have to bend the paper stack so much? Does everyone else usually bend so much, I would have assumed that a nice flat ream of paper straight from the pack should print just fine without all the bending?

one of my windmills had a similar problem, i marked the gripper with a piece of tape, it seemed to happen with the same gripper, finally i pushed on the end of the gripper to make it a little closer to the platen, this seemed to cure it. Good Luck Dick G.

When I was first learning how to use my Windmill, I would get very frustrated at it. I will admit, I was trying to bend it to my will. This was the wrong approach! You need to do what the machine is telling you to do.

I’m going to let you in on a secret that I discovered. It is a horrible thing to know, but as a fellow Windmill operator, I feel you must be made aware of the situation. So here it is: there is a Dark Ghost within the Windmill. It lives in that dank area ‘neath the platen, and it controls all elements of the operation of the press - feeding, inking, peculiar squeaks, and so on.

It’s unclear whether the Dark Ghost was installed at the factory, or if it grew slowly through the decades—its development concealed in the dark pit where all misprinted county fair tickets and forgotten gauge pins lay in their oily sleep.

What is abundantly clear, however, is that the Dark Ghost feeds on fear, doubt and disappointment. The moment it senses the press getting the better of you, it plunges out with its horrible finger and flicks your print out of register in the quickest blink of an eye, fully aware that you’re laying down the fifth color of a six color job and that you only reserved 50 extra sheets for waste, and if you miss one more you’re going to short the customer, who will demand both a refund AND a public apology.

It sounds horrible, but there is a simple solution that will banish the Dark Ghost to the deepest, drippiest parts of the press. You have to realize that you are the Servant of the Windmill — a scratcher of its itches, a massager of its kinks, an oiler of its squeaks. It will never do what you want it to do, so you have to do what it wants YOU to do.

Once I came to this realization that the Windmill would be my master, and I would never be fully in command, all of my issues went away. When it coughs, I give it a tissue. When it gets bored, I sing it a song. And when the paper won’t quite feed right, I bend that paperclip into all sorts of impossible shapes and configurations, which always seems to do the trick.

mwahahahahaha madmaudepress.

I don’t know if I have the Dark Ghost in mine, I think my Windmill just hates me. It loves nothing more than to see me covered in grease and grim and I’m sure it takes pleasure in the fact that I can’t kick it (for fear of a broken toe) or throw it out in the rubbish bin.

oh yes, there is defiantly a ghost within, and I personally think our ghost might just be jealous.

See Charlie our Chandler & Price Oldstyle was our first acquisition. He is a press with no issues, he has no qualms, we have nodisagreements, no harsh words are ever said, we ask, he performs and life is blissfully perfect.

But then their is Herbie our Heidelberg, now we personally think that he does have a complex as sitting next to Charlie he is indeed not as old, not as pretty, and maybe potentially he overheard us say that we love Charlie just that little bit more.

So every now and then his temper appears, throws a spanner in our works (just as we run out of paper, and out of ink which has taken us 3 hours to perfect to exactly the right shade). Yes indeed, Herbie has a ghost, he sneaks out of the central oiling system, gets all over our hands and makes a mess on the studio floor.

I think their might be some serious press jealousy happening in our next of the woods?

Molecular awareness and reactions of printing press relationships in relation to proximity of physical press locations.

Sounds like a possible PHD candidate dissertation.

Naming a press Herbie sounds like you are asking for trouble. I will concede that a Chandler and Prices is a far more patient and trusting machine—but they can bite.

Since nobody in their right mind would be near the platen of a running Windmill, they can only take out their problems with the stock—pulling doubles or having a sheet hang in the feeder (but not trip the sheet detector) is a true favorite—especially if numbering!

My C&P has been waiting a year and some for me to get tired of my Windmill; they truly are the patient press. Does cleaning out the sump on a Windmilll drive out the ghost? (: > O) .

I’ve never cleaned out the sump, maybe I should and Herbie will reward me. Truth is, im not exactly sure how one cleans out the sump. If you can provide instructions, i’ll report back on Herbies change of behaviour?

There are two round side plates just above the bottom of the base. With the platen open open them (they’re both hard to get too unless you lie on the floor—having big arms will not help here. Beware of stray Exacto knife blades or other hazards, but you may find all sorts of goodies, from wrenches to guides. Happy hunting!

Just stumbled across this while looking for clothing to hide my plumbers butt.

This thing looks perfect for making pins for the Windmill!

I wonder if the windmill has some kind of complex. It can be running perfect and I decide to sit on a stool next to it, and will start acting up! It also acts up if the boss comes around! Very interesting.

Forgot to mention that I have the stock not wanting to lie flat usually due to having been running through the thermo machine causing the stock to curl. Or it has been engraved before it gets to me. It’s difficult to get the score lines to register when that happens.

I’ve been taking lessons from my print master as to how best bend the stack. Seems its a whole artform in itself, and talking of which - I must get back to fanning and spreading and removing the burr from the edge practise.

In addition to “working” you stock, there’s a whole ‘nother skill set of sticking or wedging the pile. This comes in really handy when running thin stock or stock with an up curl. This can involve using wedges, or rolled “sticks” of cover stock to put a hump in the pile to help reduce pulling doubles and other mishaps. Usually these will go under the middle of the pile, but orientation can vary due to paper grain or curl.

But what causes the curl? In my experience, it is caused by an improper environment in the pressroom. Too little humidity causes the paper to dry out and contract, thus causing the curl. The sweet spot seems to be around 50% relative humidity. Now that we’re in Louisiana, there is humidity to spare. Paper stays dead flat. I just have to kick on the AC and we’re good to go. Back when we were in Pennsylvania, feeding Lettra in the winter was a nightmare. We had no climate control and the humidity dipped way down, causing the paper to curl.

we live in quite a hot climate, so we have fairly high humidity, and our paper is defiantly curling. This is the opposite reason yet we both have the same problem?

Most of the curling problems I have is because the stock was engraved or run through the thermograph first. Quite often it involves scoring the stock in half which is impossible when it won’t lay flat. They’re starting to get used to the idea that I need to score it first. In this case it’s not matter of humidity. The raised printing or engraved impression twists the stock so it’s impossible to flatten it.

Yes. Bend the stack… The mis-registration is caused by the flyout of the back of the sheet, so that it misses the gauge pin at the left.

Particularly having already run side one, any substantial impression will tend to create some curl.

I also tilt the stack, on occasion, sliding a 3 or 4 pica x40 stick of furniture under the end… or the middle.

(I see MikefromMontana has mentioned this above!)

What ever the Dark Ghost requires ;-)

The other thing, if the sheet’s not missing the gauge pin, is specific to if you’re using a frisket ‘finger’. These spring steel fingers can de-register the sheet if they are hitting the sheet at an angle to the platen, before the press closes completely. The shift can be very subtle and hard to figure out. I prefer not to use the frisket bar with heavy stock, it’s rarely helpful…

This is a nice long discussion string; referring back to the comments about using a Chandler or a Heidelberg, here is a short video of my two presses, they help each other out. Each has it’s own advantages, maybe one day I’ll run a two colour job, one colour on each press.

With the Heidelberg I found the best way to learn it was to get a stack of cut-offs and just run it; again & again….learning on the go.[email protected]/4526958442/in/photostream/



WOW, I have rarely had a prob with stock not running well. If I have a curl prob, tho, I tape a piece of furniture down first, about 2 or 3 inches from the lead edge. (experiment a little). Then I lay the paper ont op of that. voila, paper curls the right way- uh, usually.
Now, as to dropping sheets: the gripper bar (arm) should have a little bit of something with a possitive grip on it. Maybe take a piece of adhesive tape- sports tape- or something similair, or a very thin piece of cork and put on one or both sides of the gripper. That may solve the problem. Like I said, I haven’t had too much of a prob, but I don’t run with with gauge pins, either, so maybe tha’s why.

Good l;uck _ I hope you find your answer!

Will B