Die cutting 130 lb high gloss digital printed stock

First of all, like most on this site, I’m not a fan of digital printing. However, die cutting calls….
I’m die cutting on a windmill with a new die and an even jacket. I have a problem with all edges looking ragged. The printing is black on both sides and the ink or toner is cracking at the edge which shows the white. It makes it look like a dull die cut.
I was told if they used a double rich toner, there would be no way of fixing it.
I am hoping someone has a trick up their sleeve.
Thanks.

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I trust your makeready is under the jacket and not behind the die. If your diecutting is even reduce under jacket packing by a few thou then apply scotch tape to surface of die jacket. This works some of the time

Thanks Mike. I’ve tried scotch tape and masking tape. The blue painter’s tape makes it look the best but still looks bad.

A few untested thoughts, for what they are worth (maybe nothing):

If the stock is high gloss, it is most likely clay coated. Perhaps instead of the toner coming off the paper, the coating, under the toner, is coming apart or cracking off the base sheet.

I wonder…….if you put the paper in a high humidity atmosphere for a while, whether that would make the coating more flexible and less brittle. (If the paper was printed with water base ink, you obviously should guard against making it damp enough to cause the ink to migrate or bleed).

I don’t know how complicated the die cut is, but I’m wondering again……..if you die cut the job, stack it perfectly and clamp it, whether you could sand the edges a little, to make them smoother.

I’m not a diecutting expert, but I wonder if you are cutting something out of the art, or cutting the art out of a sheet, with the rest as waste. If the former, or the latter, it would seem that the cutting edge should be toward the saved part, not the waste or centered on the cutting rule. If it’s centered or facing the wrong way it has to push some of the stock aside to cut and if it’s pushing the “saved” side it will buckle it and it will flake if it has such a tendency.

Bob

Thanks for the input.

Geoffrey- I have sanded edges before after using a dull die. The edges on this job are smooth. They just don’t look smooth because the toner has flaked off.

Bob- The die is center bevel. I will look for a side bevel die on the shelf and see if that makes a difference.

I’ve die cut other 130 lb gloss digital before with no problems. The toner looks different on this job so I’m thinking that has something to do with it.

Mike, question for you about the packing under the jacket or the die. I was taught, by a die cutter who uses the same platen as us, to add the packing behind the die. This was the process:
Back off impression all the way, then creep slowly until the first part of the die cuts through.
Then add thin hard packing behind the die in the low areas until its all cutting evenly.

This has worked very well for me so far, even kiss cutting labels with complex 6-up shapes. It’s much easier to add tape and packing to the die than to remove the jacket each time you need to make an adjustment. I am curious about the advantage to packing behind the jacket or the drawbacks to the way I’m doing things.

Ridiculous suggestion: toner is plastic, and melts around 110°C, but it possibly becomes plastic before that. Maybe drag a toaster oven into your shop and pre-heat the stock so that the toner is a bit soft (maybe 80°C ish) when you die cut?

That’s an interesting idea,but my wife says,” NO WAY !”
I am going to wait and talk with the copy people.

danielheff
Many people make ready behind the die because it seems easier. The reasons are many for makeready under the plate too many for this forum.
example you put a bit of mylar behind a cutting rule to get one spot to cut, now you have a teeter totter in your chase.

How about another ridiculous suggestion of edge painting the diecut edge? With the digital printing being black, even if the edge painting has a dull look instead of the gloss toner, you’re not having to match a color and it should be better than the white stock showing through.

Bob- It doesn’t matter on the bevel. Even if you cut the stock in a paper cutter, the edges still crack. I would have to guess it’s because of the double rich toner.

Little Acorn - I tried that on a small lift and I think it looks great. I used a fat sharpie. It doesn’t rub off. What do you use for paint?
A sharpie would take along time on 1000 pieces.

toner and clay coated stock can be a problem. too much dirt and you are trying to cut dry mud

it is late at this point, with the die already made, but, a thick stock can be die cut more easily with a “long center bevel” rule. this type of rule tends to not separate the stock as much during the cut. thicker stock tends to “tear” as the knife goes through the sheet.

Dennis,
I’ve never actually had a need to edge paint anything yet. I was going from the discussions I’ve read on this forum.
Good Luck,
Diane