20-04-2014, 04:11 PM
Thanks for reading my diatribe and for your observations Tony.
I used to use two or even three acetates taken at copy shops on laser printers before I got the HP Photosmart, which was superb. It printed so well on acetates that when the ink had dried you could run your finger tips over the sheet and feel the raised lines. This meant that PCB layouts with fine tracks were never a problem. I've attached a (not very good) pic of a couple of small PCBs with narrow tracks in close proximity which were exposed and developed from masks made on the Photosmart, and a pic of two PCBs from masks made on the Epson SX535.
The trouble isn't simply the lack of density of the print, it's striations in the print and when two are printed off to place over each other, the missing print is in the same place. You'll notice that in the second pic - two PCBs made from Epson prints - that I've had to touch up one quite extensively with rub down transfers due to the poor quality mask. Quite frustrating really, because if I print the artwork onto photo-paper on the Epson, it comes out really black and dense, but whatever setting I use for acetates makes no difference, which comes as no surprise because Epson themselves have confirmed to me that their printers won't satisfactorily print onto acetates and they've never claimed that they do - they just keep quiet about it.
That said, I've no idea whether an HP 6520 would be much better, but at least it does have a transparency setting, as did my old HP Photosmart.
I've still got an aerosol can of 'Transparentiser' spray intended for making paper transparent to UV light in the way that WD40 does, but I didn't find it very effective. It's become less of an issue for me as the amount of constructional work I do has declined markedly since I lost interest in amateur radio and I make few PCBs these days, and I have so many other calls upon my time - something I'm sure you'll be familiar with Tony!! (The first pic of PCBs are for an audio filter and a small transmitter which never got built, and never will).
I've heard varying degrees of success/failure using the iron-on laser technique Tony, and it certainly cuts out a lot of the effort in exposing and developing UV boards, but as I don't have a laser printer I can't give it a go. The main issue seems to be the need for a very hot iron, held firmly down for perhaps 15 minutes. I've heard that cheap glossy magazine paper is better for printing on than actual photo paper and is easier to remove when ironed on. Also, it's claimed that if photo paper is used, that 'satin' photo-paper is better than glossy. Scores of videos on youtube of course. EG:
http://www.bing.com/videos/search?q=maki...er+printer&docid=608032760658856378&mid=CC9C098AADC9911661AACC9C098AADC9911661AA&view=detail&FORM=VIRE8#view=detail&mid=C80F2BF91B4E019E91D9C80F2BF91B4E019E91D9
I used to use two or even three acetates taken at copy shops on laser printers before I got the HP Photosmart, which was superb. It printed so well on acetates that when the ink had dried you could run your finger tips over the sheet and feel the raised lines. This meant that PCB layouts with fine tracks were never a problem. I've attached a (not very good) pic of a couple of small PCBs with narrow tracks in close proximity which were exposed and developed from masks made on the Photosmart, and a pic of two PCBs from masks made on the Epson SX535.
The trouble isn't simply the lack of density of the print, it's striations in the print and when two are printed off to place over each other, the missing print is in the same place. You'll notice that in the second pic - two PCBs made from Epson prints - that I've had to touch up one quite extensively with rub down transfers due to the poor quality mask. Quite frustrating really, because if I print the artwork onto photo-paper on the Epson, it comes out really black and dense, but whatever setting I use for acetates makes no difference, which comes as no surprise because Epson themselves have confirmed to me that their printers won't satisfactorily print onto acetates and they've never claimed that they do - they just keep quiet about it.
That said, I've no idea whether an HP 6520 would be much better, but at least it does have a transparency setting, as did my old HP Photosmart.
I've still got an aerosol can of 'Transparentiser' spray intended for making paper transparent to UV light in the way that WD40 does, but I didn't find it very effective. It's become less of an issue for me as the amount of constructional work I do has declined markedly since I lost interest in amateur radio and I make few PCBs these days, and I have so many other calls upon my time - something I'm sure you'll be familiar with Tony!! (The first pic of PCBs are for an audio filter and a small transmitter which never got built, and never will).
I've heard varying degrees of success/failure using the iron-on laser technique Tony, and it certainly cuts out a lot of the effort in exposing and developing UV boards, but as I don't have a laser printer I can't give it a go. The main issue seems to be the need for a very hot iron, held firmly down for perhaps 15 minutes. I've heard that cheap glossy magazine paper is better for printing on than actual photo paper and is easier to remove when ironed on. Also, it's claimed that if photo paper is used, that 'satin' photo-paper is better than glossy. Scores of videos on youtube of course. EG:
http://www.bing.com/videos/search?q=maki...er+printer&docid=608032760658856378&mid=CC9C098AADC9911661AACC9C098AADC9911661AA&view=detail&FORM=VIRE8#view=detail&mid=C80F2BF91B4E019E91D9C80F2BF91B4E019E91D9
Regards, David.
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
BVWS Member.
G-QRP Club Member 1339.
'I'm in my own little world, but I'm happy, and they know me here'
