Splotchy Blacks -- Any Ideas?

[keith1]

He actually tried to pack with 24lb yesterday but the blanket was too tight. I told him to try 20lb but he didn't want to. Maybe I can get him to pack it in a couple days.

20lb packing is way too thick. Half that. At least.
And follow Alois' advice re plate to blanket pressure. All pressures & roller conditions are important.
You could have farmed the job out to better equipment by now and saved money & grief.

Keith

 

[keith1]

And follow Ink Man's advice on the ink. Often, especially on small presses where there aren't enough rollers to mill the ink properly, an ink that's too stiff can be the problem. Thin the ink. How much is a matter of experience. I often used to thin using overprint varnish rather than tack reducer.

 

[jpfulton248]

Thanks to everyone here. My understanding is that after changing blankets you should always check pressures... he doesn't do that because all the ink gets everything messy. I think the last time he checked was 3 or 4 years ago because I asked him to. Right now he has one blanket packed with 24lb and the other not packed at all because the blanket was too tight to get it on the cylinder even without the packing.

I'll check on ink but, D Ink Man: You don't have to be a dick.

Also, one thing I do want to try at some point that was suggested here is printing on our 20lb until we get everything looking decent and then switch to a smoother finish mid-job to see what the difference might be. I do believe this will improve our quality of solids a bit more.

Learning that our press operator isn't completely full of it regarding the fact that the nature of our press is that it will never be able to do great quality in some areas has actually been extremely productive to me so I thank you all.

We have certainly considered farming out our long runs on many occasions. If our business starts to change (in terms of ratio of long runs to short runs) that is something that could be a possibility. Other possibility would be getting another digital press and going all digital. Obviously our printing cost would skyrocket but our labor cost would reduce and our quality improve.

Thanks again all.

 

[Alois Senefelder]

Hello jpf,

Given the limitations of you press, with a competent printer you should be able to


achieve better results than at present. Your lack of printing knowledge does not help,

you seem to believe everything that you are told by your present operator,

"Everything Messy" changing a Blanket ---- rubbish !!!!!!!! not if you know

what you are doing, which HE does not

Regards, Alois

PS BUY the right size Blankets

 

[jpfulton248]

Hello jpf,

you seem to believe everything that you are told by your present operator,

No, I actually believe very little that he tells me which is why I posted here in the first place and why it was actually nice to hear people here say that our press really does have limitations in terms of quality. That is something he has been preaching for years.

 

[keith1]

No, I actually believe very little that he tells me which is why I posted here in the first place and why it was actually nice to hear people here say that our press really does have limitations in terms of quality. That is something he has been preaching for years.

That's good to hear
Before starting my own business I had moved to a new city. For the sake of a pay packet I ended up working part time at a couple franchise operations. The owners at both knew 'everything', and despite the fact that at that time I had about 30 years experience under my belt at various positions within the industry, I - according to them - knew very little to nothing. They were the boss.
For the sake of full disclosure; I then found work at a larger shop. By that time however . . .

It's actually one of the reasons that motivated me to hang up my own sign. I saw many print buyers being misinformed and over charged because they were dealing with inexperienced personnel/print shops.

I get that it can be a difficult situation when it's your business - your money & reputation on the line, especially in a small shop where there are no other employees to bounce ideas off.
It's always good to be on friendly terms with other shops in your neighbourhood. I've found nearly all to be only too happy to offer advice. Those that don't care to join the community, generally, are those that don't last.

As a final bit of 2 cents. You have an old machine, and just like an old car, there comes a time . . .

Best luck!
Keith

 

[AP90]

JPF, Im curious as to how long your inside runs are that it wouldn't be beneficial from a financial standpoint to move the guts of your booklets digital. Even the Xerox D series printers do a good job on B&W and are pretty cheap. The clicks can get down to .005 or less depending on volume. And they're fast for digital machines with the D125 doing 125 pages/minute. I can't see the insides being too long of runs if your already printing the covers digital unless its variable. Just something to check into, especially seeing as the digital machines like that do not require and experienced "pressman" to run them.

 

[jpfulton248]

JPF, Im curious as to how long your inside runs are that it wouldn't be beneficial from a financial standpoint to move the guts of your booklets digital. Even the Xerox D series printers do a good job on B&W and are pretty cheap. The clicks can get down to .005 or less depending on volume. And they're fast for digital machines with the D125 doing 125 pages/minute. I can't see the insides being too long of runs if your already printing the covers digital unless its variable. Just something to check into, especially seeing as the digital machines like that do not require and experienced "pressman" to run them.

As an example today we are running what is considered a large job for us which is 20k sheets of 11x17 1/1. At .005 per click that would be $200 just for the maintenance (not including a lease/loan). Plates probably cost us $35 plus the cost of a bunch of aggravation and about 4-5 hours of press operator making his $X per hour plus the cost of ownership of the platemaker and press (both pretty inexpensive knock on wood). With all of that said, most of our offset jobs aren't this large and the cost comparison would probably make a lot more sense at a click rate of .005.

Currently we have a J75 with a click of .02678. Between the cost and speed obviously this type of job just wouldn't make sense on it. Thanks for the suggestion. I'll look into it further.