Alignment off

Windmill here…

I’ve been printing for a few months now but when I try to run multiple colors I get into a little trouble. I can’t get the (vertical?) alignment to register correctly. It varies about 1/8”, maybe a little more. I thought that it was because the paper wasn’t always picking up from the same height, but no matter how hard I tried to control it, nothing worked. Any sage advice for me? Can’t run a press shop if you can’t even register.

Thanks - D

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I’ll ask the obvious question: are you running with it set for guides? If not, the gripper will hold the paper through the cycle and you will get some variation in alignment.

jonsel is right, if you have the grippers set for running with guides and you are not using guides the paper is released for a second. Also, if the paper is not square you will have this problem.

I am a novice who’s come into a Windmill. My experience trying to get mine registering properly involved two problems:

1) A broken part in the register system. It was very hard to see and took me a while to notice, but there was a small crack in a support bracket on the platen which holds the rod on which the lay bar is supported. This made the whole system squishy, and the lay bar would raise to different heights each impression.

2) A bend in the gripper. Not that the whole gripper arm was crooked, but at the point at which there is a hole in the gripper that the side-guide pokes through, the small piece of metal bridging that gap was bent it. It was bent far enough that when the gripper opened to release the paper into the guides, it was still held snugly against the back of the gripper and couldn’t fall.

Read up on common problems and rule those out. After that you’ll have to find what’s wrong with your press. Make sure sheets are making it to the side guide, if they’re not, speed up the press maybe? Make sure they’re not bouncing off the side guide, if they are, slow down the press.

Make sure the left feed standard is set to where it should be. Every few days I have to move mine back as it slowly moves out of place. Make sure the front feed standard is parallel to the gripper.

Find out if it’s a register problem that always happens, or if it’s every second sheet. If it’s every sheet, it’s not a gripper problem, but if it’s every second sheet, then you need to find a problem with a gripper.

If you stare at the press long enough, and stop it during the feed cycle enough times, you can usually realize what the problem is. The register system is fairly intuitive.

I am not using guides. I’m not very learned on the process… does anyone know of a guide or tutorial to introduce me to using guides - and gauge pins?

modernman, thanks for the information. I will check to make sure that the lay bar isn’t changing heights. As to whether or not its a gripper problem, I’m not sure. It isn’t exactly every other sheet, but it isn’t every sheet either. The alignment can jump up or down up to a quarter inch between impressions, but sometimes it doesn’t, sometimes it stays in place for a few. I will pay more attention next time to variations between the two grippers and make sure they are consistent with one another.

Although there could be any number of things physically wrong with the press, it is very likely that it is an operator error on my part.

Thanks, D

Hi D,

Read the instruction manual. It doesn’t offer “an introduction to printing with guides” but if you read between the lines enough you can figure out all you need to know.

If you are printing without guides, the change in register between sheets should be minimal. Grippers will normally be bent a bit, so there could (as on my press) be a 2 or 3 point difference in register between sheets. If sheets are varying in register up to one quarter inch (18 points if I’ve done my math right) while printing without guides, something strange is going on.

The paper could be slipping out of the grippers. Are they closing tight? Does the strip of rubber inside need replacing?

Is blast forcing sheets too far back while they are being picked up by the sucker bar?

If you want to produce fine multicolour work, you should probably forget about this problem and head straight for printing with guides. It will take some experimentation, but just read the manual carefully and follow all of the instructions on the press itself (set the appropriate guides on the lay bar, set the left feed standard the appropriate stop, engage the lay bar, make the adjustment on the gripper head so that the grippers open.)

Finding someone who’s run a Windmill to teach you will be your best bet. Calling around to print shops and asking for people to help is tough; I’ve found it’s best to ask paper reps. If you have an account set-up with a paper company, like xpedx or something, you could ask them as they visit lots of shops. When I needed learn a bit about line-camera work my paper rep hooked me up with an older gentleman who was tickled to be showing someone how to use one.

Hope that helps, if you have any specific questions feel free to get in touch, but trying to explain all the ins-and-outs of printing with guides in writing would be worth neither of our time.

Paul

I’ve been told the gripper variance can be a fair amount and is different from press to press. 1/8” is certainly possible if you’re not running with guides.

Before looking into deeper problems, I would start first with trying to run with guides. You can download a manual for the windmill from Boxcar Press’ website, if you don’t already have one.

Cool, thanks everyone. I’ll assume that the variance is simply the way of the world and invest myself in learning how to use guides properly. It would be ideal to find someone who knew everything about my press and could tell me everything I need to know about it, but, alas, such is not the case.

I’ll see what I can do.
D

Maybe if we knew where you are located someone could help you, there are a lot of windmills out there, most operators would be glad to help you. Dick G.

I’m in North Mississippi - there is a gentleman nearby who used to work with them, but I haven’t been able to get hold of him yet.