Ultrasonic washout for photopolymer plates

Ultrasonic units are marketed as being suitable to wash out photopolymer plates for use in the manufacture of rubber stamps - http://www.rubber-stamp.com/polysonic.htm Does anyone have any direct experience of, or comments on, their use for washing out plates intended for use in letterpress work? If satisfactory, their use might prove a great help in DIY plate manufacture.

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Hello, yes, ultrasound is one of several methods for washing out photopolymer plates. Bit expensive though, can’t imagine how this would prove a “great help to DIY” since all one needs to wash out a plate at the elemental level is a tub, a horse hair brush, and warm water, and perhaps, a timer.


I’ve got to concur with Gerald on this one. While an ultrasound might work very well, I’d think it would be a bit expensive considering the relatively low volume in a DIY type of operation. The only advantage that I could see to it is that it would eliminate having to get your hands wet….. but if that’s a problem, you can always use rubber gloves.

Gentlemen, very many thanks for your responses.

What I had in mind when posting was the discussion on “Polymer plates? Create them yourself or outsource…” http://www.briarpress.org/13321 where Gerald, a professional platemaker amongst his many other skills, has some pertinent things to say about professional standards.

I’m a DIYer because I can neither afford nor need the professional solutions and, anyway, enjoy the challenge of trying to replicate professional standards. In my world, money is scarce and a platemaking machine is neither affordable nor justified, but time is almost endlessly available. That means, for example, that ultrasonics need not necessarily be expensive for a maximum plate size of A4. Surely, commercial ultrasonic equipment seems to be unjustifiably expensive, but ultrasonic transducers are not and it is within the realms of possibility to fabricate an ultrasonic washout unit oneself at not unreasonable cost.

This approach struck me as more promising than the methods described above by Gerald, since they would ensure greater consistency of process, one of the many shortcomings of hand techniques. Likewise, consistency of exposure, via a self built exposure unit and vacuum back, and consistency of drying, via a self built heater, offer greater chances of success and merely require a degree of intelligent design and the willingness to experiment for best results. A promising starting point for the first two items features in the article “A home-made photopolymer platemaking system” by Brian Allen on the PPLetterpress Yahoo Group, founded by Gerald.

But the suggested method of manual washout in Brian’s article, which proved difficult above about 8” X 6”, seemed capable of improvement without going down the mechanical brushing path of the platemaking machines. Hence my posting. If anyone has detailed advice about ultrasonic washout techniques and schedules for letterpress photopolymer plates, I’d be most interested to hear from them.

Kind regards, Sukitawdry

Suki…. I do understand what you are saying, but in my experience hand-washout does not result in lesser consistency than machine methods, if you pay attention to what you are doing. I’ve washed out many, many plates in the 11 x 14 size range without difficulty…. and with excellent results, even on fine type. I’ve found that exposure is a lot more critical than washout.

That being said, I applaud your approach to platemaking. Like you, i don’t think one needs to spend an arm and a leg to gain plate-independence. In fact, I discussed that very point a few days ago in another posting. If I were to build a washout unit though, I think I’d use a warm water spray unit, combined with a water-powered rotary brush, much like a car-wash brush.

Dear Winking Cat,

I very much like the idea of a car wash! - water spray and whirling brush - but think it likely to be a little difficult for me to implement mechanically. Surely, once fabricated, an ultrasonic washout is going to be very much simpler to use, and without brushes and other parts to wear out or need adjusting? My only reservation at this stage is that, although touted for rubber stamp work, ultrasonic washout seems not to have been widely written about (at least here) in connection with letterpress. Any pointers to references, protocols or tales based on experience would be appreciated.

Kind regards, Sukitawdry

PS My small commercial ultrasonic unit is a gift for watch work, such that I will never return to the whirling cleaning carousels of yesteryear!