DIY pcb making problem

[sss]

for 2 years i've been making pcb's (photoresistive) with my inkjet printer (on transparencies) and i always had to use couple of sheets one on top of the other to make the ink dark enough ....

now i'm thinking of upgrading the printer so i can use only one transparency sheet that will be dark enough .
first ,i thought that laser printers are better for this ,but yesterday i tried one ,and the results were much worse then a regular inkjet printer (yes, i used the special laser transparency film)
so ....
does anybody got any printer to suggest ?
inkjet /laser,i dont care ,as long as it can make the job done...

[pinkmouse]

I seem to remember that Epson do a special ink and transparency kit for making PCBs by the photographic method. It might be worth googling, I'm sorry, I can't remember where I saw it.

[VT67]

SSS

In the past I made a few prints on transparent film with an Epson Stylus Color. It was set at max resolution, 1440dpi, and the prints came out black as charcoal. It takes a while before the printout is finished but the result is magnificent. Forget laser printers, they are absolutely useles for this kind of job. My two cents.

Regards

[astouffer]

I get good results with double sided glossy photo paper for color laser printers. It feeds through my old laserjet 4L with no problem and works better than the $1.50 a sheet stuff from digikey. This site has some good info.

http://www.fullnet.com/u/tomg/gooteepc.htm

[poobah]

SSS,

No direct experience here... I always send my boards out or cob something on vectorboard.

1) Could it be that you are using too much light when you "burn" the board... either time or intensity?

2) And I second GeWa... try high-res... and "darker".

3) Have you ever tried running the film through the printer twice... have to make sure you guide it correctly... and some drying time.

[Eva]

Some friend of mine owns a laser printer that obviously costed a lot of money. He went quite puzzled when I showed him the resuts that I'm getting with my HP7550 on generic inkjet transparency sheets from some Spanish manufacturer. Paradoxically, I saved that inkjet from being dumped to the nearest trash bin as it was malfunctioning and the previous owner replaced it by a laser printer. I only had to clean it and buy a black ink cartridge in order to make it work fine again, so it costed me almost nothing.

The key to get good results seems to be to adjust both the drying time and the ink load to the maximum, so that the ink is put into the sheet in gentle amounts but in very thin overlapped layers. Also, hot air has to be applied to the sheets for an hour or so after printing in order to dry the ink completely. Printing a full page in such a way may take two or three minutes plus drying time (and lots of ink if there are ground planes), but the result is far better than what I was getting from laser-based machines in local photocopier shops (which always seemed to be running out of toner!)

BTW: I also bought 100 of these generic inkjet transparency sheets for 50 euro.

[tvi]

Laser printer pinholes are a major problem, but you could try a fixative like:
Laser Buddy
or
Ultra-Black

Laser printing should be a lot cheaper especially if you are doing ground planes.


regards
James

[sss]

Originally posted by GeWa
SSS

In the past I made a few prints on transparent film with an Epson Stylus Color. It was set at max resolution, 1440dpi, and the prints came out black as charcoal. It takes a while before the printout is finished but the result is magnificent. Forget laser printers, they are absolutely useles for this kind of job. My two cents.

Regards

thanx ,i'll check that one out

[sss]

Originally posted by Eva
Some friend of mine owns a laser printer that obviously costed a lot of money. He went quite puzzled when I showed him the resuts that I'm getting with my HP7550 on generic inkjet transparency sheets from some Spanish manufacturer. Paradoxically, I saved that inkjet from being dumped to the nearest trash bin as it was malfunctioning and the previous owner replaced it by a laser printer. I only had to clean it and buy a black ink cartridge in order to make it work fine again, so it costed me almost nothing.

The key to get good results seems to be to adjust both the drying time and the ink load to the maximum, so that the ink is put into the sheet in gentle amounts but in very thin overlapped layers. Also, hot air has to be applied to the sheets for an hour or so after printing in order to dry the ink completely. Printing a full page in such a way may take two or three minutes plus drying time (and lots of ink if there are ground planes), but the result is far better than what I was getting from laser-based machines in local photocopier shops (which always seemed to be running out of toner!)

BTW: I also bought 100 of these generic inkjet transparency sheets for 50 euro.

Eva ,after printing the sheet i let it dry for 24 hours before using it .
i'll check for HP7550 also

[Eva]

With my setup I get quite good results with just two sheets attached together, and three sheets are enough to kill all visible light even when you look at them while they are placed directly on the surface of a fluorescent lamp.

I usually employ three sheets, as that turns UV exposure into quite a fool-proof process. I can't appreciate much difference between 3 or 6 minutes of UV when it comes to develop and etch the board later.

Concerning HP printers, as their ink cartridges have all the injection hardware built in, theoretically any printer based on a "56" cartridge like mine would produce the same opacity, so don't look for a single model only (also, mine is quite messy because it uses two more color cartridges specific for photo stuff). Only resolution and the quality of the paper-feeding mechanism may vary from model to model (I believe mine to be over 1200dpi).