4281Re: [PPLetterpress] Re: troubleshooting
- Jun 3, 2005Harold
My comment about higher grade plate brand had nothing to do with Toyobo.
Neither Jet or Toyobo are what I would consider top grade plates. But
they are both adequate for most letterpress applications. I've run my
own comparison tests of these particular brands as well and my suspicion
is that these differing plates need differing exposure and washout times
to provide optimum detail and subsurface strength, so it is essentially
misleading to compare them or any other plate brand in the manner that
But the hardness rating of a plate has less to do with how deep your
impression can be than it does with ink acceptance and transfer. Any
photopolymer plate, no matter brand or hardness or thickness or relief
depth, is going to splay under increased printing pressure (that is self
evident to any seasoned printer). And "gain" is a normal consequence of
increased impression with the letterpress process. If folks need deep
impression without splay they would be better off going with a copper
photomechanical engraving mounted on a metal base. There is a technical
reason for the limitation of thickness and relief (and hardness) in
regard to letterpress formulated plates.
Just out of curiosity, would you have switched brands if Toyobo had
surpassed the Jet in your comparison test?
Good luck with the press move.
Harold Kyle wrote:
>On 6/3/05 1:22 PM, "Gerald Lange" <bieler@...> wrote:
>>94FLs are a tad softer than other plates, don't know if this is the culprit or
>>not. I'd recommend a hardness rating of 65-70 Shore D minimum. You might also
>>think about switching to a higher grade plate brand.
>Well you finally stirred me to write with this comment!
>Re: "softness". The hardness of the 94FL is 62 shore D so I think you'd have
>a hard time seeing the difference between it and your recommended range of
>65-70. The difference is insubstantial. Also, should you want a harder
>plate, Jet makes a 94HFL that has 80 shore D. We at Boxcar Press have a job
>shop running the popular "deep impression" printing exclusively from the
>94FL. The plate's printing shows no evidence of "softness".
>Re: "Higher grade plate", Gerald, your opinion of Jet 94FL plates are of
>less quality will not be borne out in a side to side test of the material. A
>rep selling Toyobo Printight visited Boxcar Press' shop earlier this week
>and we proofed a test plate of Printight KF95 next to the Jet 94FL material.
>The Jet plate showed more detail and, at the same time, exhibited less gain;
>this is with a rep selling Printight monitoring the processing. After
>extensive testing, I've come to conclude that the only plate that gives the
>94FL a run for the money is the BASF WH95. The cost difference between these
>plates makes the 94FL much more desirable option. I would be happy, by the
>way, to scan a proof of the side-by-side comparison of Printight and Jet
>plates when I get a chance.
>Re: Jessica's platemaking "plaid" problem. I'm problem solving this with the
>manufacturer of the machine, who apparently can furnish a vacuum table
>adaptor to make the grooves less noticeable. I want to get more information
>before I promise you that this is possible. Apparently, the adaptor is a
>"diamond-plate" material that sits in the vacuum table. I'll post to the
>list to let you know when I have more information. The problems you're
>experiencing, though, appear to be from the platemaker and not the plate.
>Re: Jessica's platemaking button problem. I'm sorry I didn't touch base with
>you about this sooner. I remember calling you several months ago to let you
>know that I may have found the possible problem, but I guess we never
>touched base. Apparently, the powder-coating of the steel might have made
>the opening for the vacuum switch too small. The extra pressure on the
>switch causes problems in it working properly. You can file the opening to
>be a little wider see if the switch works better.
>Sorry not to be able to write sooner. I should be loading my trailer right
>now for a press move...
>Fine Printing / Digital Letterpress Supplies
>Delavan Center / 501 W. Fayette St. / Studio 222 / Syracuse, NY 13204
>315-473-0930 phone / 315-473-0967 fax / www.boxcarpress.com
- << Previous post in topic Next post in topic >>