Windmill ghosting

I have alot of trouble with ghosting even with bold type, not even large heavily inked areas. I have tried the rider roller but regardless of my adjustments it seems to add such weight to rollers that it is a big mess and looks far worse than the ghosting i am trying to fix!

is it that my ink does not have enough pigment? Not sure how to keep adding ink without greatly impacting the color i am trying to achieve.

any advise is greatly appreciated!

carolina

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Make sure your rails and trucks on the form rollers are clean. This always solves the problem for me. Form roller adjustment is critical also.

it could be a lot of different things. it might be the ink you are trying to run, you could try a black ink and see if you still have the problem, if your rollers are old they can give you problems, i always deglaze my windmill rollers every few months.

check all the above , also check the tension of the distribution roller to the duct roller and to the first ink train roller ,a tip that helps spot a problem here is to look for a flashing effect in the ink on the roller surface , if all points are contacting along the surface the ink will appear to be flat and dull ,if there is a point of no contact the ink will appear shiny at one ofthe ends of the roller s, this is only obvious when the press is in ink feed position and the press running .
If you see the shine you alter the tension at that end or replace the roller if upon inspection it has a low spot .
You would not normally require a rider on the form inkers for type unless you have a really bold letter above a large solid in the form . you can see that problem on the form itself in most cases , same with a solid reversal sat in the form above a solid area .

The problem with ghosting also can be from too transparent ink or used (hard) or poorly adjusted ink-rollers.Change used rollers: the rubber surface of older rollers will become glossy and over-smooth. At the same time, as their hardness increases, the edges bulge out in a trumpet shape. More pronounced abrasion becomes evident.When maintaining rollers, only use the appropriate cleansing agents; a weekly application of wash paste removes lime deposits, and will regenerate the rollers.
Make sure you have optimal balance between ink and dampening solution.

I have run platens on and off for just over thirtythree years , and the damping has been a problem for years !!!!
I think SASO77 may have mis posted that one !

Peter, i can’t seem to find the dampening system on my windmill, can you tell me where it is??? i’ve been running this press for at least 25 years now, i’m sure the water system is dry by now.

If the problem persists with a rider roller, then it wouldn’t be ghosting. Mechanical or roller ghosting happens when the roller returns over the form and the depleted area overlaps the image area, causing an area that is under-inked along one edge in line with roller travel. A rider will redistribute ink over that area and remove the ghost. The ghost varies with the difference in overlap, can be relatively wide in the worst circumstances.
A similar but different condition also occurs when rollers are set too low. They can wipe the ink off one edge of the form, also in one direction of roller travel. But the wipe will just be at the edge of all elements of the form, and fairly narrow.

I have had a problem with a repeat/ghosting today, i was using rubber base ink which was reduced slightly, the ink is 95% transparent white.
I cannot alter the % of white would not reducing the ink help??

Altering the ink is not going to cure ghosting , I would turn the forme through 180deg and try that if the rider is no help …
Dick , its behind the flibbery digit , just above your whatyermaycallit !

Thanks Peter.

Peter…..if I’ve got this right it’s got got to be in front of the thingamagig…right? Only once did I have a problem with ghosting. You’d I’d know better than to run a windmill in a haunted house!

Should have been…You’d think I’d know better……..

Image is symmetrical so turning it was no help
stiffer ink was no help
altering roller settings was no help

but changing the stock cured the problem!

it was dry on Friday when i first ran the job but the wettest day for 30 years on Monday when i changed the stock so perhaps damping does make a difference!!!!!