HELP! Polymer Plate issue!

Hi guys,

I have a Heidelberg Platen Letterpress and am very new.
I’ve got polymer plates but the trainer thats training me seems to think that the plates is only used for printing the ink on the paper only and not making an impression on the paper.

We tried exerting the pressure but its not leaving an impression, but only printing the ink.

Please can you assist? Anyone?

Vanessa

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What are you trying to do? Are you wanting to emboss the paper with the image or print the image with the ink.

It sounds you wanting to use a printing plate to emboss paper. It will not work

well, if you are looking for the “indented” look that is popular now you will need to hit against something that is thicker and softer than normal. if your instructor is “old school” he probably will shy away from this look as years ago it considered sloppy presswork.

Hi there,

Eric: Yes I want the indented look thats popular now. I have a base from boxcar press, is that right?
Does the polymer plate need to change in order to achieve this indented look?
Is more pressure needed?
My instructor doesnt know what I’m talking about he thinks i just want to print the image with ink and emboss using a a metal plate.

Aaron: I’m trying to achieve the “indented look”….

Show him the look you are trying to achieve. A lot of what is printed on the Boxcar site would be done on one of their many Windmills, I assume. If you have it printing perfectly, start printing with a thick, soft paper and it should be as easy as turning up the impression a TINY bit.

Paul

As ericm mentioned, this is a battle of traditional vs. progressive printing.

Most folks on here would not word it as I did though. They would probably refer to it as a battle of “proper vs improper” printing.

I’ll leave it as that. There are many topics on Briar Press regarding impression vs. kiss printing if you are interested in delving into that debate.

As for your question. There could be a few factors involved:

1. Add more packing (paper) behind your typman paper. This is an over simplified solution though - there is much involved in making sure you’re printing with precision, even if you are going for an impression.

2. If you’re printing a very thin or firm paper, it can sometimes be a challenge to produce the desired impression. Many letterpress printers who print with impression use special soft cotton paper. It tends to accentuate the impression.

Again, the above advice is over simplified. It is worth researching and practicing.

Be careful adding packing to a Windmill. If it exceeds 3pt there will not be clearance for the gripper arm and you could damage the press.

Great thanks!

Is the deep impression “look” achievable with the polymer plate?

That is almost exclusively how it is done.

way back, this impression was not desirable. it is one thing to imprint a bunch of the same thing as after drying they will “nest” together with one image dropping into the same on a sheet below it.
but, as a lot of printing was done for books and such, the page behind is different than the one above. this would not allow the pages to nest and thus a book to lay nice and flat with many pages.
with the onslaught of quick printing, computer gen copy and all this high tech stuff, i can see/understand the appeal for something that gives the look from years ago. especially for special occasions.
this new appeal to indentation is kinda like when they offered “chrome bumpers” on cars. they worked no better than regular steel but “sure like the way it looks!”
to each his own. and the one who signs the check wins….

You can achieve the results you want with the Boxcar base and polymer plates on your windmill. It is a delicate balance between the packing behind your tympan sheet and the impression lever on your press and roller height. My instructor also was “old school” and thought impression was a bad thing. I have sent him samples of my work with heavy impression and I think he is impressed, saying “if I still had my print shop, I would hire you.” Hope this helps.

Photopolymer plate material comes in different durometers, and different papers will allow different amounts of compression. Neither material has been identified here. It isn’t always just a case of “more pressure!” because sometimes it is the photopolymer that is giving. You can’t do more than the materials allow, even with a Windmill. Copper photoengravings are actually a better choice for heavy impression than photopolymer, but more expensive.

par_imp does have a point here…the weakest link… make sure it is not your Plate/Die.

The plate that I am assuming you are ordering from Boxcar should be hard enough to bite into Lettra, Savoy or even a thick cover like those available from French, although not to the same extent.

I mentioned before that you should not overpack a Windmill as you can hurt the press, which is very important, but when printing with a lot of bonk it’s important to consider how hard your packing is. If you are packing under your tympan with regular bond or tag like some do, your makeready will not be as hard as it can be, and investing in some non-slip, hard packing from somewhere like NA Graphics can help considerably.

If the impression is showing through on your draw sheet or any of your packing, you’ve turned it up too hard! Once it’s made it’s way through your paper and is impressing your packing you’ve achieved the most bonk you can, turning up impression past this point will not change the print, only hurt your press. The caliper of heavy stocks will vary between about 0.012” to 0.025” so that is margin of impression you are working with—no point printing through the paper!

Dampening will help as well, especially if you’re printing solids.