ink “loading up”
I’ve been printing for about 6 months now without too many problems (thanks to you guys and gals on Brair press!) But now I’ve gotten my biggest job. A huge invitation with lots of fine type on four different runs 8000 impressions total. My first run is 2000 on a 4- ply non-rag stock 7x5.5”, the type area is 6x4” (black ink). I’ve set up the job and am running, all the fine type is coming up nicely but at the top of the page the larger type is doing funky things. I’ll be running and the first three words will start running light and the bottom two words will load up with ink (the type is running vertical). I can’t figure it, the rollers are touching the top words first it would seem they would get the ink first. I look at my plate and see that the top is not getting ink ,so I’m thinking maybe I should take some tape off that side of the rail, but to no avail. The pressure is even on my make ready. This is my first experiance with this phenom. I’ve had the same tape on the rails for about two months could this be it? Any help would be great!
What press? Are your rollers keyed to the trucks? Sometimes if they aren’t the rollers will spin a little at the bottom and if you have heavy coverage it’s possible for the rollers to over-ink part and pull ink off other parts on the return trip to the ink disc. Try double-rolling it. That will help redistribute the ink evenly.
Bob
Thanks Bob ! double-rolling it did the trick. (I’m on a kluge 12x) Kind of a hassle though, I hope I don’t have to do that on the whole job! Is having to double-roll a rare thing? or am I going to have to get used to it on a regular basis? I’ve printed other invits. birth’s, Lths, biz cd’s and never had this problem. Thanks again!
Patrick
Patrick,
My experience is that if you have large solids it is necessary to double roll to get satisfactory uniform ink coverage, but it really depends a lot on the press and the job.
Check to be sure your rollers aren’t spinning at the bottom of their travel, even a little, or skidding on the rails — that makes the under-inked portion from the downward pass move a little so it doesn’t register with the image going back. The under-inked areas will pick up ink from the image and the still-inked areas on the rollers will add ink, creating the kind of problem you had.
Another idea is rider rollers, which some production platens did use, usually between the form rollers. They add a lot of ink capacity for large solids, but you may not have the clearance for them with the grippers.
Glad to be able to suggest a helpful technique.
Bob
How does one fix if there rollers are not staying keyed? (mine have a little play and im not sure ifs causing issues or not.)
But im having some issues similar to Patricks where some areas are not inking up (like one word or a stripe of the plate) and or some areas are getting gunked up with ink. Or even more annoying 2 or 3 prints looks okay and the 4th looks awful!
My press has rubber rollers and adjustable trucks (that are not very easy to adjust..) I checked the roller diameters right at 1.5 inch. All seem the same. Rails have a few spots that have “small” dents in them..
patrick - if you don’t have rider rollers for that kluge you should try to find some. They help to eliminate ghosting and provide even coverage for solids.
stewartdesign - you might need to shim your rollers to keep the trucks keyed. If the rollers don’t turn with the trucks they can skid across the form and/or the ink disc.
truck_diameter.jpg