AB Dick 9850 suddenly printing light.... help!

Hey all,

My AB Dick 9850 all of a sudden is printing ridiculously light. I have to put the blanket pressure all the way to 1 or 0 to get things looking halfway acceptable, but even that's not cutting it.

It was running just fine a few weeks ago. Then I ran metallic silver and think I didn't clean the press well enough. I thought that there was metallic glaze on the rollers, so I scrubbed the heck out of every roller I could remove, and washed up numerous times. I even swapped out the rollers with some newer ones I had around, thinking that would solve my problem, but to no avail.

I've re-striped the new form rollers since I put them in, ink / water balance is decent, but it seems like I need to run way less water than I should be. But if I knock it too far back, I get toning. Regardless, with the amount of ink in this thing, stuff should be coming out wet and shiny but even with the naked eye, I can see spots in the letters.

What can it be? Is the blanket glazed over? Is it shot altogether? Did the change in weather mess with my fountain solution ratio (I've cut it back a little bit since it's colder now)? I can't figure it out. I'm working on a time-sensitive job and I want it to look as good as possible for the client. My technician can't come til Monday. Any ideas? Help!

 

change the blanket

 

Actually, I think found the problem: my ink ductor rolling was getting hung up, thus preventing ink from constantly being fed to the ink train. I work out of a garage that gets cold in the winter and had this problem last year too when the ink keys were too far out and the thickness of the ink held up the doctor roller. I think things are working fine now... probably couldn't hurt to change that blanket pretty soon though.

 

lantz-xvx
What type of damps do you have? What type of plates are you running? Also it's a good idea to check cylinder nips once a year on small presses.
FSA

 

remember all you printers out there beware of shrinkage when it get cold

 

Shrinkage. Heh.

The dampener is just the regular aquamatic that comes standard on it. I use poly plates. Not sure how to check the cylinder nips; is there some good info out there on how to do it? I'm fairly certain the ink ductor roller was the problem, but we'll see what happens next time I ink up. I'll let the impression off to where it normally is and see if I still have problems. Thanks for the feedback, y'all.

 

Well, as it turns out, my press is still doing the same thing. It takes forever to get up to any sort of color, and when it finally does, it's much too light to be acceptable. The ductor roller is working just fine now, and I even put on a brand new blanket yesterday. The image looks nice and crisp on the blanket but the finished sheets are just way too light. The plate seems to be receiving ink fine, and even if I get my rollers so inked up that they hiss, the printedg sheets look like they don't have enough ink, or too much water - though I cut back the water a ton, so much that it just feels wrong.

Anymore ideas? I haven't yet checked the cylinder nips, I'm hoping my repair guy can do that if I can get him out to my shop today. My mind is totally boggled.

 

lantz-xvx
Alright poly plate are developed with an activator and a fixer, when the activator get weak you get issues, like too much water, when the fixer (acid bath) evaporates the water in the mix, you get blinding or weak image. If you have a densitometer you need to start measuring a solid or colour bar to track and set a baseline of what is good and not. Also your fountain etch maybe too strong on the weak imaged plate. Your problem is why we don't run poly plates, they have a made many printers loose their minds thinking it's the press, when it's a lazy person in the camera or art dept. Check it out, let me know.
FSA

 

I've never had this problem with poly plates before. One thing that I have yet to check out that my repair guy told me about was the master cylinder pressure knob. I recently took the side covers off the press, and he says it might be possible that when the master cylinder pressure knob got put back on, it knocked the pressure to the wrong setting. It certainly seems possible, as I never have to mess with that and these issues did sort of come out of nowhere. I'll keep folks updated. It's driving me nuts....

 

put your blanket in a sink with hot water and let it sit for awhile at least an hour then leave out to dry overnight. did this recently and some smashes that were pretty bad went away. yeah

 

Switch to metal plates you wouldn't have any problems like this! I don't know why people bother with poly they might be cheap but that's what your getting is cheap garbage. Metal metal metal!

 

Just a thought, but what if you put some paper packing under your blanket and see if that gets you a better transfer of ink to your sheet.

 

run a hair dryer over the ink in the ink trough before running it up on the rollers, you will see a massive difference. i too work in these cold conditions

 

I love the idea of running a blow dryer over the rollers, I have fanned them till my wrist hurt before. My solution has been to use a 80-100 watt conventional bulb in the lamp and point it directly on the rollers. The heat generated evaporates the excess water. I even rest it on the ink ductor to get it close. The T-head has been a challenge though. Think I will experiment with the wife's hair dryer for it.

I once used paper plates... they frustrated my to no end. I switched to metal about 6 months ago and love them. Only problem when you are working out of your garage is shooting the film and burning the plates.

 

On your plate to blanket adjustment has 6 number settings with settings between numbers. Maximum pressure is full clockwise #1. I normally adjust pressure with plate mounted and setting on #3 to maximum pressure. This gives option to pack plate for changing length of print or using thinner and thicker plates. Do you know what the support arms are? The adjusting screws are visable through frame cut-outs on both sides by the blanket cylinders. Interested on how to make and check adjustments, just ask.