Photo-poly plates thickness .006 vs .004

I’ve decided to go photo-poly plates on my kluge 12 by.
now do I go .006 on plate thickness which gives me a .045 relief or go .004 plate thickness which gives me .027 relief. I have experiance on Kluges with foil and embossing and de- bossing. With embossing the deeper the die the better the emboss (depending on paper weight) and the more raised the deboss die is the deeper the deboss and I am thinking that the the higher the image on the plate the more relief I will acheive .Is this premise true for letterpress printing on a kluge?

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Patrick

Your numbers don’t make sense. What kind of base are you using?

Are you saying .006 for .060 and .004 for .038? They both give the same relief. But it depends upon your base height. Together, plate and base, must equal type height (.918).

The only rationale for a .060 is the type of press you use, it doesn’t actually give you a deeper relief (the relative reverse relief depth of photopolymer plates configured for letterpress is fairly consistent, no matter what the thickness of plate).

A Kluge, C&P, hobby platens, etc., will likely benefit from the .060 thickness because of roller adjustment considerations, which are less precisely controlled than on presses such as a Heidelberg or Vandercook.

Gerald
http://BielerPress.blogspot.com

Thicker plates don’t have deeper relief? Not in my experience. Certainly diffrerent carriers have different thickness (film, steel, aluminum) but beyond that it is the photopolymer layer that varies between different plate thicknesses. I have used plates with designations of MS152, HX145 and DS100 from the same manufacturer, and each had the same thickness of steel backing, only the photopolymer changed, and it is the photopolymer that determines the relief (unless you don’t washout down to the carrier).
What’s more, isn’t that the whole point of Boxcar’s marketing program of “deep relief” plates?
However, to the original point, does deeper relief give you better depth when punching the paper, I would guess not unless you are whacking something really thick really deep, and then photopolymer may not be the answer.

Parallel

A “relative reverse relief depth” is a technical term that refers to the depth from surface to bottom of counter or similar. There is no significance difference between the thinner plates and the thicker plates in this regard. This has to do with imaging concerns rather than debossing. If you want to whack away, and get good results, go to copper.

Other than with the advent of Boxcar’s promotional efforts, I can’t say that anyone considered photopolymer an ideal material for “deep relief”—and for good reason.

Boxcar’s marketing program is what it is. They do know who their market is. But they do also indicate what these are actually for if you look seriously enough. And they do say on their website that for their own work they use the .038s.

Gerald
http://BielerPress.blogspot.com

So the term refers only to depth of non-image detail within an image area, but not to surrounding non-image? That I can understand. With such jargon a definition would help.
But in that case, I’d also say that I get better counter formation and better reverses on thinner plates. Reproducing a wood engraving on a thinner 100 plate I might hold both highlight and shadow detail with one exposure, where with 145 plates I may have to mask, doing dodge-and-burn exposures. Otherwise shadows fill and highlights are weak (or gone).
Personally, I hate it when deep impression work leaves high mounds of fibers up between letters and words and lines, resulting in distracting light and shadow that conflicts with legibility: looking down a well to find a letter. The fact that counter areas can’t rise up as high in the printed piece is a good thing. But perhaps legibility has become a concern only of typographers and not designers or pressmen.

parallel_imp, when I have reproduced fine wood engravings to photopolymer I dont use kreen, just
clear acetate. Because I dont use kreen the plate
has no shoulder therefor the plate does not plug while printing in the shadow area. My understanding of the deep relief was that the newbees would have less trouble inking
their plates,deep relief would have nothing to do with
impression. The commercial graphic design these
days has no concern for legibility, only to grab your attention long enough so you buy what their selling.
Busy chaotic is the norm, The designers have all these
tools and gimmics available on their desktops and they
use them all in anyway they can all the time. KIS is so uncool
today. best james

Actually, the thicker plates around .060” are very close to 16-gage original photoengravings, and so standard .854” blocking wood or lead high-base could be used; this was the standard thickness at the origins of type-high (as opposed to wraparound) photopolymer plates. They weren’t invented later by Boxcar to suit platen press printers. And that’s the height of PatMag magnetic base as well. There is also another Elrod strip material that works with 95-100 thickness plates, it is the same height as blank Linotype slugs. I don’t think there were any traditional plate materials of that thickness. And if background inking was a concern, photengravers wouldn’t use a thicker plate and etch deeper, they would rout the dead matter, much more efficient than extra etching. Or, mount the plate on a base close to image size. It seems to me that with photopolymer today there is a lot of wheel-reinventing going on, compounded by the practice of using one large base for all sizes of work. But then if you don’t know about the traditional stuff or where to find it, reinventing is the only option.
Interesting, James, exposure without krene. This is with a standard exposure by bank of UV tubes, rather than point source? There will always be diffusion with a bank exposure, but that change in cover material will reduce diffusion that much is remarkable.

parallel_imp

1} Yeah, that is sort of how it works. Basically, you aren’t going to get anymore “real” relief than you are supposed to.

2) Yes, the thinner plates have a more stable structure, so are more viable.

3) Yeah, brutality to paper is just wrong. Slam bang thank you mam mentality. Amazed it is fashionable.

In regard to the Kreene thing… I did once ask my rep if I could use transparent acetate rather than translucent Kreene. He said no, and he has never steered me wrong. I suspect one could get the same result (as suggested) with Kreene and reduced exposure. But worth looking into.

Gerald
http://BielerPress.blogspot.com

Sorry guys ment .06 and .04. Had good imput on the subject.Getting into this I had the assumption that the deeper the impression the better. I’ve seen jobs done on Proof-presses and it is very deep and I’m trying to copy this on the Kluge. It seems there are two schools of thought on the subject.