Hickies

[fireplug55]

OK, you are running an sheetfed offset press as a board printer.
Your boss says he wants you to come up with a way to eliminate hickies from the process.
What do you tell this person?
How do I eliminate not reduce the amount, eliminate!

 

[Ajax]

Tell him to reduce them is to wear dark sunglasses and to eliminate them is to close your eyes. But seriously, you'd have to run the board through blank once to get most of the loose fragments off. Also, when printing, put a blank plate on your first open unit (if you have one) and run your waters. You'll pull way more dust that way than you normally would dry.

 

[Cornishpastythighs]

Doyle Multimodal™ Sheet Ceaners

Its a start!!

 

[fireplug55]

Got them, minimal help at best. Also hickey picker rollers.

 

[Ajax]

Fine, tell your boss to order lint free stock.

 

[Green Printer]

A low shear ink with a fountain solution that has Hi blanket lubricating properties will lower the amount of hickies. When accompanied with a differential speed dampener the hickies will be extremely reduced or eliminated.

 

[RGPW17100]

Buy Kromekote

 

[Raymond Ramirez]

I hope maybe there is a print planet Guru reading this post. We assume that the stock is causing the hickies. Where are you running your ink? are you pulling way back to hit color?. With a thin ink film this will cause the ink to be like glue.... The curve in prepress will need to be changed for the stock.... This will have you riding on the cusp of the links and water balance.......

 

[Bob Peterson]

I have to agree with Mr. Ramirez. I have a few questions:

1. Does the press have enough units where you can utilize the first unit to dust the sheet?

2. Are you running ink designed for board stock i.e. (low or extra low tack)?

3. What are the target densities you are running to?

4. Are the plate curves for this profiled to GRACol or SWOP?

With this info I we might be able to help you resolve the problem, or provide recommendations.

 

[Dan Roll]

I have seen a feeder that was rigged up with an extra air compressor set up to blow across the board (above and below, in opposite directions) at about a 10 degree angle away from the press. I don't remember how they did the timing (solenoid valves tied to a small cam switch I think), but this device (while loud) blew an astonishing amount of debris out of the feeder into the press room. You could easily see particulate matter blown out of the feeder from each sheet. I do not know if this eliminated hickies, but it must of reduced their instance by a bunch. If I remember, this device was removed and replaced with a less satisfactory vacuum device in an attempt to do a better job. I think Earl Wimels (Whimpy) was involved with this, but again, this was back in the nineteen seventies and my memories of that time are a bit cloudy.

 

[REYES1377]

With a thin ink film it would be like not spreading enough peanut butter on your bread, nothing but crumbs.

 

[Alois Senefelder]

Maniacs !

Maniacs !

I have seen a feeder that was rigged up with an extra air compressor set up to blow across the board (above and below, in opposite directions) at about a 10 degree angle away from the press. I don't remember how they did the timing (solenoid valves tied to a small cam switch I think), but this device (while loud) blew an astonishing amount of debris out of the feeder into the press room. You could easily see particulate matter blown out of the feeder from each sheet. I do not know if this eliminated hickies, but it must of reduced their instance by a bunch. If I remember, this device was removed and replaced with a less satisfactory vacuum device in an attempt to do a better job. I think Earl Wimels (Whimpy) was involved with this, but again, this was back in the nineteen seventies and my memories of that time are a bit cloudy.

It just goes to prove they are still about; I'm glad that I don't have to get sheets of B1

80/100 gsm coated paper via a Stream Feeder on a VLF Heidelberg (10.000/15,000) IPH with a

Typhoon Blast of Air impinging on the sheet transportation



Why not put the onus back onto the Board Manufacturer by Rejecting ??


Regards, Alois


P S I use to drive the Newsprint Manufacturers mad by rejecting any defective Reels of Paper

 

[Lennyr]

Do all of the above plus reduce the tack of your ink and run the press as fast as it will handle the paper.
This causes an easier release from the blankets and the paper tends to not pick as much.
Are your hickeys coming from the plate or the blanket?
If your running uncoated stock try running a sizing varnish before you print. This will glue the fibers to the sheet, but
may cause drying delays.