Hey everyone,
I just joined this group, and I thought I'd let you all know how I'm doing with an Epson Stylus 740 I picked up for $10. I stripped it down completely: the pizza wheels are gone, original loading tray, four of the middle pressure rollers, the collecting tray, and the case. I found two white, plastic tabs used to adjust the head height. They were buried so far under the case, they could not have been designed to be user accessable, however, adjusting them seemed to have worked for my purposes. I also modified the "+<-->-" lever to raise the print head as high as possible.
I had to hack open the rear tray, and keep a small section of it, becase that houses a gear driven notched wheel, which activates an opto-sensor. I suppose this sensor tells the printer whether or not the tray loader is working properly. I made a temporary holding tray out of thin cardboard and taped a test PCB to it.
I just did this all last night, and I have not had much time to debug. Anyway, here's the problems I'm having so far: to begin with, alignment is a big issue, so I'm going to have to eventually make a better tray, and some sort of guide rail. Also, tray loading is tricky. I can only load the tray a few seconds after the carriage slides all the way to the left, which consequently would have activated the original tray loader. The delay accounts for the time that would have been necessary for the paper to travel from the tray to the rollers.
Also, there are two sensors that detect paper position. Once is located on the carriage, which I haven't messed with. The other is a basically a tactile sensor which activates an opto-sensor. That is, as soon as paper hits the arm, it moves out of the way of the emitter/collector closing the loop. It doesn't seem to be very efficient on my hacked version, since the tray is set lower than where the paper would have been. I can't quite think of a way to adjust this yet other than to go the Volkan route and build and use a "paper emulator."
Other than that, the setup seems decent. I didn't buy any MIS-PRO inks, and I didn't clean my test PCB (since I wasn't actually going to use it), so when I did my first test run, the ink looked very blurry. I'm not sure if my poor PCB/ink combo was the cause, or if I just need to adjust the print head alignment.
So, there you have it. My little contribution to anyone who has a Stylus 740 that they want to print PCBs with. Of course, if anyone has questions, feel free to ask. Also, if anyone has any suggestions, I am more than open to hearing them. I'd like to work these bugs out quickly. I also found a C84 on Craigslist for free, so hopefully I can pick that up and try to modify it, if the guy still has it.
Paul Symansky
SymTech Labs, Sr. Project Coordinator
(954) 478-7285
http://www.symtechlabs.compaul.symansky@...[Non-text portions of this message have been removed]