Photogravure: Preparing a Photopolymer Plate, David Kachel

[@michaelrizzo6150]

David, first time I tried this film adhesion method I struggled with bubbles, and it also became apparent to me I needed to relocate my darkroom. That's been accomplished so tonight I will try adhesion again. Mike

[@davidkachel]

I don't recall anyone having a problem with bubbles. Are they under the polymer film after you attach it? Or inside the polymer? Anyway, if you continue to have the problem, you might want to try the method I am now using... I bought a garden mister at Walmart (cheap, plastic, with a hand pressure pump on top, not the best "mist" but good enough for this purpose. Skip the tray full of tap water.) Put the dry PETG on top of the glass or other working surface on the squeegee table. Use the mister filled with distilled water instead of the tray of tap water. Mist the PETG substrate, then mist the inside surface of the polymer, after removing the covering, of course. Gently lay the misted side of the polymer onto the misted PETG, so you can reposition it easily if necessary. Then follow the original procedure for the squeegee process. If you have any problems, just pull the polymer back off, re-mist and try again.

[@michaelrizzo6150]

@@davidkachel Yeah, bubbles under the polymer, not in it. Thanks, I'll try this new method. I actually souped a plate this morning, just a rough test plate to get a feel. I think my sodium bicarbonate wasn't properly processed into sodium carbonate, not much in the way of development going on. There was a bit of confusion about the concentration for development, is it 1 or 2% ?

[@davidkachel]

@@michaelrizzo6150 One percent. I know I made a mistake somewhere and wrote/said two percent. It probably wouldn't make much of a difference except to shorten the processing time, but no point in wasting chemical supplies.

[@NH-bm9vy]

I haven't been able to find ImageOn here in the UK, only this fine photosensitive film and removing the top layer is the bane of my life! Even on fresh photosensitive film, the top layer is a nightmare to remove. It always ends up with damaging and eating into the image area. If you've discovered any hacks since the making of this video please don't hesitate to share! THANK YOU for the doubling-up demo, was trying to figure out how best to do this too, as the film i have is so fragile/flimsy! 🙏🏾

[@davidkachel]

To my knowledge, there is only one retail source left on Earth for Imagon HD. However, that is GOOD news, not bad. Imagon HD is really DuPont MM550 which should absolutely be available in the UK. There are also other products just as suitable or even better, available in the EU. Eternal E8020 is excellent. So is their 9220. Go to my web site: davidkachel.com. Click on "Books" then go to the bottom of the page and download the free paper on dry film photopolymers. That will bring you up to speed on these materials. (If you don't have my book, you can buy it on the same page. Imagon HD costs 13 times what Eternal's products cost and 6 or 7 times DuPont's products. Sources in Europe are listed in the paper and calling around should provide additional information. Let me know if you need additional help. If the covering is difficult to remove it means one of two things. 1. You didn't allow a freshly prepared plate time to dry, overnight. 2. The material was stale. Some times hard to tell. It simply tends to get darker and slightly purple. dk

[@NH-bm9vy]

@@davidkachel Thanks for getting back to me, and so comprehensively too! Much appreciated! Will look into your top tips and see how I fare. I also suspect you are quite right about my not leaving the plate to dry for long enough. Will employ more patience next time; let's hope that does the trick! 🙏🏾

[@NasserAlhameli]

Thank you David! Would you please tell me would you get good edge embossment with this PETG 0.020 thickness? Did you try another thick PETG?

[@davidkachel]

The plates make somewhat less of an indent that a copper plate or the readymade polymer plates, but I don't find it lacking in any way. You might. If you wish a deeper indent, you can use .030 thickness or even thicker, but you may run into problems. For example, your inkjet printer may prefer suicide to accepting plates thicker than .030. I don't actually know because I haven't tried thicker plates (others have used .030 with no reported problems). Also, as the plates get thicker, the price goes significantly higher.

[@NasserAlhameli]

@@davidkachel Many thanks David!