Weird Stock?

[Richard]

I back up a customers bus. card gang. The set up is 80lbs. uncoated.. prints good, get to the custumers stock, it gets lighter and lighter with each pass. It is a smooth something stock.
I got the kompac at least water, ink up. What the hek? Pack extra on blanket. Its like it repels the ink. I had varnished the other side yesterday. Not excess powder. I have never seen this before. I am just putting an 8 up black ink backup. The non varnished side.
I am sure its the stock. Yet I still have to back it up. I can get 2-3 good ones out at time.
I dectected "not enough packing" right away. Did I over pack? and up set something on the ryobi 3302? Like plate to blanket? Why does the set up stock print right? ... I don't know.

care to comment? thnx.

 

[Al Ferrari]

Do you have a lot more unprinted customer stock to try?

It sounds as if the job stock being backed up accepts (takes away) much less water than the makeready stock for some reason, so that soon the excess water left in the system overpowers the ink-water balance. Ideally you would need to use a lot of the customer stock (in the same condition) as makeready sheets.

This commonly happens in situations where synthetic stock is the job stock and ordinary paper stock is used for makeready.

Al

 

[Deleted member 16349]

Do you have a lot more unprinted customer stock to try?

It sounds as if the job stock being backed up accepts (takes away) much less water than the makeready stock for some reason, so that soon the excess water left in the system overpowers the ink-water balance. Ideally you would need to use a lot of the customer stock (in the same condition) as makeready sheets.

This commonly happens in situations where synthetic stock is the job stock and ordinary paper stock is used for makeready.

Al

Hi Al,

I like your train of thought on this.

It will be interesting to see how this turns out.

 

[Richard]

got answer

got answer

The tech within the corporation replied to the problem. There is a sensor witnin the high tech 3302 that thinks the varnished side is NOT a sheet, so impression shuts off. He said that most pressman don't know of this sensor. I didn't, and there is no mention of it in the manual. He thought it could not be done. Oh by the way Al, you never have enough customer stock to waste. I fed in two uncoated stocks, then a good stock. It took time to collate this sequence... So 2 set ups, 1 good , etc..... And impression shut off each time a good one went thru. I had to really ink up the rollers, because impression was off each time a good one went thru. You see the sensor thinks the varished under side sheet is a misfeed. I did a very good varnish job! Varnish over a black. I would have never figured this out. Anyway, those cards are DONE!
thnx.

 

[Deleted member 16349]

The tech within the corporation replied to the problem. There is a sensor witnin the high tech 3302 that thinks the varnished side is NOT a sheet, so impression shuts off. He said that most pressman don't know of this sensor. I didn't, and there is no mention of it in the manual. He thought it could not be done. Oh by the way Al, you never have enough customer stock to waste. I fed in two uncoated stocks, then a good stock. It took time to collate this sequence... So 2 set ups, 1 good , etc..... And impression shut off each time a good one went thru. I had to really ink up the rollers, because impression was off each time a good one went thru. You see the sensor thinks the varished under side sheet is a misfeed. I did a very good varnish job! Varnish over a black. I would have never figured this out. Anyway, those cards are DONE!
thnx.

Glad you got the problem solved. There are always new surprises in printing. A never ending story.

 

[Al Ferrari]

I had a 3302 until a couple of years ago when I had to close my shop, but I don't recall such a sensor (you'll be surprised how fast you forget these things when your turn comes).

Your tech may very well be right, but why didn't you notice the handles moving up as they lifted the rollers? At least you didn't mention it, although you did mention you suspected a change in printing pressure, which did not seem connected to me.

Al

 

[Richard]

Thats right Al, I should have heard the dis-engagement of impression, which would not make the machine turn off. It was near the end of the day, and I was incredulous of the un-printing going on.Thankfully I didn't waste too many of the customers stock. Today my boss has a peel n stick job that needs to be varnished. Oi!! A Matte finish this time. The last one was High Gloss Varnish. I don't have a can of Mattel. Any comments on this?
Everything I know on varnishing, is what I have read in the Van Sons Pressman handbook.
And a retired pressman, who commented that don't put too much on. And use powder.
I used the water system. I have never tried NO water. Have you?
thnx.