Photopolymer Plates

Today, June 22 is was looking at a Jackson Photopolymer unit on Ebay. It’s $400 bucks. I think it can be used for Metal Back Polymer Plates for Letterpress. I have a Ludlow Polymer unit so I don’t need it, however maybe you Polymer Plate users can give us some feed back on these used machines for future use.

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This will only help you expose. You still need to develop it (with brushes, usually).
There’s no vacuum either. So it wouldn’t be a super great machine. For those functions you could build it your self for really cheap. Just a timer and UV lamps.

You are right. My Ludlow unit has a vacuum pump on it’s second level for making “daylight” film from a computer. But I prefer to use a offset printers vertical camera to “shoot” my films on matte litho film in my darkroom. I’ve been doing that for years now. And yes , you still have to scrub the polymer with a brush. I use the “Boxcar Brush” to scrub the polymer plate. I also use a ultra-sonic unit instead of the brush. But this stuff is for rubber stamps. For metal back polymer plates I use the brush. The ultra-sonic unit is not for metal-back letterpress plates.

I’d never heard before of washing photopolymer plates with ultrasonic cleaner.
Does it help with conserving finer detail that otherwise are lost with the brush? Does it work for plastic backed plates?

I think ultrasonic washout is used with liquid photopolymer, maybe detergent washout, which is for rubber stamp production.

@parallel_imp, so you don’t think it could work for plastic backed plates? Why is that?

Yes, the ultra-sonic washout unit is for liquid polymer rubber stamps - not for letterpress plates. Briar Press members have advised me NOT to use the ultra-sonic wash-out on metal back polymer plates. Use the brush. Also the plate must be finished in a convection oven for final hardness or durometer for letterpress use. I’m not sure you can do that with a plastic backed polymer plate. Double sided tape won’t hold out for long. Even worse, getting the plastic die off your chase base will most likely destroy the printing plate.

Regarding the ultra-sonic washout out unit: It’s advertised as holding finer details than the brush. However, I’ve never used thin type styles such as 20th Century Light or even worse Bernhard Fashion in my printing. Even using hard foundry type over the years I have always had a bad feeling towards these type fonts. I love Greeting Monotone - but too thin for my use. Any comments?

Since my post here two months ago, the Jackson Photopolymer machine appears to have been sold. These guys go for a $1000 bucks. Meanwhile as enriquevw points out you still have to make a negative film to expose your polymer plate on this unit. Years ago I made a glass and wood frame with foam to expose polymer offset printing plates with a UV “sun lamp”. Worked great- no vacuum pump needed. This same set-up could be used to expose your vellum print out from your laser printer to make a daylight negative for photopolymer plates. The same homemade exposure frame can then be used to expose the metal-back “hard” polymer plate for letterpress use. Hand wash with polymer detergent and a “Boxcar” brush and dry in a low heat 200 or less convection oven and post expose on top of the frame with the same UV light source. I’m rambling here - you get the idea?

Today, 9/4. there is a Technal Photo Proof Frame on Ebay for $19.95. Take a look at it. This a good example of what you need to expose daylight film to make the negative film for the final photopolymer plate. You will need to make a UV Light source to expose both film and metal back polymer. The seller wants $33 bucks for shipping. Yikes! I say make ‘em an offer! The daylight film, vellum paper for your laser and the metal back hard polymer you can get from Jackson Marking Products. I buy the 4x5 sheets of hard polymer. I use a metal back polymer shear to cut the plate - not tin snips. The snips will buckle the plate and make it very difficult to adhere to your magnetic base on your letterpress. I use the Patmag Base with double side tape for my plates.

Here is some cool stuff regarding metal back hard polymer plates: The plate shear will cost an easy $165 dollars for a 12 inch shear with long handle. My short handle cost me $85. A Jackson Model MB-100 Hard Polymer Plate Exposure and Drying unit for 4x8 plates an easy $1980 bucks. I about fell outa my chair on the price. However, considering the price of foundry type and the type cases to house let’s say fifty fonts,
we might be looking at a bargain here. A small sheet of metal back polymer costs $13 bucks. Do we have the start of a discussion here - or what?