Anybody already used photosensitized PCB ?

[HX1]

I'm needing a method to make PCB with professional quality, already I tried several methods but did not get good results.
I was thinking to use photosensitized PCB as these:
Fotoboard from MegaUK: http://www.megauk.com/pcb_laminates.php
http://www.bungard.de/content/view/25/76/lang,english/
http://www.computronics.com.au/kinsten/prices/
http://www.mgchemicals.com/products/600.html

Somebody recommends ?

[FriskyFerret]

I used the Datak pre-sensitized boards years ago. Worked well. The developer back then was an harmless aqueous solution mixed from a pre-measured packet. The results you got were as good as your mask quality.

I printed onto an overhead transparency with a LaserJet II (give you an idea of how long ago that was?) set to maximum print density. If the toner isn't as thick as possible you can get millions of microscopic pinholes that give the copper a rough texture and depletes the copper thickness.

It was better to actually first burn an intermediate mask using the film they also sold. So you burned a film with your artwork mask printed on a LaserJet then used that new, intermediate film to actually expose the PCB. The reason for this is the film was very high contrast and would not reproduce all of those microscopic pinholes from the LaserJet toner. Much cleaner linework and solid fills.

Professional quality? You can't make 'professional quality' PCBs at home. (Unless you're German and clinically obsessed. Then you can make you own twin turbine jet engines in your garage.)

Nowadays I suppose the micro-fine, highly opaque toner in todays laser printers might be sufficient to go without an intermediate film.

[vovchik02]

Positive20 give good result. 0.35mm Cu .27mm space. 1 layer.
Inkjet printer give fotomask.
Bat good plated hole for 2 layer can be get onle in profetional factory.

[jzaghal]

Hi,

You can produce your own sensitized pcb's using DryFilm and a cheap Laminator.

PM me for good source of DryFilm and bare board PCBs.

Bye.

[jwildes]

Hi,

I prefer use a Press-n-Peel paper (blue) to make PCB.
Me and my friend try with many kinds of chemical products and don't work fine.
But with the blue paper it is easy and fast.
PM to me if you need more informations.

Regards,

Jwildes

[HX1]

Hi guys,

Im going to congratulations to everybody for the helps.
But by what did I researching I going opting for use the Press-and-Peel by be a easier approach and very good results, in the future I will try to use dry-film.

[  ] 's

HX1

[Walkura]

All my prototypes i make with photo sensetive plate (standard issue from the component supplier)
The positive i make on the computer to print it with inkjeton (i think it was) silkpaper .
As uv source i use a *homemade* a4 scanner which i emptyth and filled with 6 uv tubes (4 minutes).
Developing i do with 16 Gram of caustic soda on half a liter of cold water
(do take care it desolves good before you develop, a grain of caustic can ruin your traces)
With this concentration you have it relative good under control .
Being a barbarian i usualy carefully take it out (after lets say 5 to 10 seconds)
That way i can flush & wash of the purple goo and i keep clear visibility in my caustic .
You can see by the teint of the copper if your photographic layer is removed
(you can check with multimeter (carefully) the photographic layer isolates so the part to be etched away should conduct)
Ferro chloride shouldn't be the problem ,when things go wrong it was already wrong after developing .
When you work tidy and keep your eyes good open you can make a good quality prototype boards .
Ofcourse it will never be professional quality
,but if you want that i would say prototype ,make it bugfree and have it etched and masked by profi buro's

[satanicoo]

Ever considered milling your own PCB's?
They may not look that good, but for hobby projects you get them made fast and cheap.
Just use eagle to create your PCB, with pcb-gcode plugin to export to CNC language, and mill them away.

Surprisingly easy!

[FriskyFerret]

Yeah...right, except for having the CNC mill part, its a good suggestion. Just when I think I've seen the dumbest post, a new winner appears. The casual closing "surprisingly easy" really pushes you from 2nd place to 1st place. Good job satanicoo!

[HX1]

Ever considered milling your own PCB's?
They may not look that good, but for hobby projects you get them made fast and cheap.
Just use eagle to create your PCB, with pcb-gcode plugin to export to CNC language, and mill them away.

Surprisingly easy!

Do you know if eagle can export to HPGL (.plt) format too ?

[  ] 's

[markhao]

I do not know about eagle, in expresspcb, you can make image, like .bmp

[eSilviu]

Yeah...right, except for having the CNC mill part, its a good suggestion.

well... it took me about 2 weeks to make a CNC mill, precise enough for milling PCB....
total cost was about 100$ (and 3 old printers)

but now I make all my boards (single or double) with CNC.
Surprisingly, it's faster than taking a empty PCB, paint-it with Positiv20, wait to dry, expose, corrode.

[Kwaigo]

CNC machine is very interesting idea. I`m think about building one. But how about control software? Can you tell more about your experience?

[satanicoo]

Do you know if eagle can export to HPGL (.plt) format too ?

[  ] 's

I haven't seen any export options on eagle, try to check in eagle's topic for some info on it.
http://www.sonsivri.com/forum/index.php?topic=4771.0

well... it took me about 2 weeks to make a CNC mill, precise enough for milling PCB....
total cost was about 100$ (and 3 old printers)

but now I make all my boards (single or double) with CNC.
Surprisingly, it's faster than taking a empty PCB, paint-it with Positiv20, wait to dry, expose, corrode.

Indeed!
My 270$ machine:





Drawing a pcb to check layout:

CNC machine is very interesting idea. I`m think about building one. But how about control software? Can you tell more about your experience?

I dont have much experience actually, you may check on www.cnczone.com forums, they have everything about building your own milling machine.
Control software, i use mach3, windows-based and very good one, worth the 160$.
For free there is TurboCNC, wich is DOS based and does the job.

I draw the schematics on eagle, then i use the pcb-gcode plugin that automatically exports the pcb to milling language that mach3 understands, just like that!
I just can't see anything easier than this.

Yeah...right, except for having the CNC mill part, its a good suggestion. Just when I think I've seen the dumbest post, a new winner appears. The casual closing "surprisingly easy" really pushes you from 2nd place to 1st place. Good job satanicoo!

Completely uncalled for.
I hope the majority of your 3xx post's aren't about mocking people.

[eSilviu]

Indeed!
My 270$ machine:

Well, this is my cheap machine:

and as you can see, it's working hard! 

Some results:

[Biggles]

I printed onto an overhead transparency with a LaserJet II ...

I use a similar method, with a few changes for the last 10+ years. I used to use a HP Laserjet 6L, but I find the inkjet printer I replaced it with when the laser died was just as good.

So with the risk of overlap with your method FriskyFerret, here is how I make good quality prototype boards (one or two layers, up to 2oz copper) before getting them made commercially:

1 - Design your PCB. Any program will do.
2 - Print onto inkjet transparency film.  I find the 3M works best with HP ink. Try avoid cheap inkjet refills, the quality will vary. If possible, try print mirror image, but this is not essential, unless you have very fine track.
3 - Expose pre-sensitized copper clad PCB  ( I use the ones from Mega  - very good.), by peeling the plastic coating off the pre-sensitized board and placing it directly onto the artwork in the UV light box.
4 - Develop the boards. I use the liquid solution from Mega.
5 - Etch with Ferric chloride - yes.. messy, but good results.
6 - Drill and shape your pcb.
7 - Strip the etch resist layer
8 - Cold tin solution to keep good solder characteristics and the board also looks better.
9 - Sometimes when I finish making the pcb and soldering all components, I spray the board with a conformal coating. The final appearance - and importantly - the function of the PCB is good as production pcb without soldermask.

8 & 9 is also possible with CNC board to improve appearance/life? !

I estimate the investment cost over CNC is a little cheaper, simple plastic tub with fishtank heater is good for etch and tin solutions. The developer I find easier and faster to heat up a small bottle in a tub of hot water. Chemical cost is not that high. I also use a small hobby pcb drill with a simple vertical motion. Do not try to drill your pcb holes by hand with a dremel, you will break many pcb bits.

I would like to do CNC oneday, but I already have an easy ( ok, easy method for me ) to make PCB, and my design quantity is low, so for now I stay with my method. Good luck with your choice.

[Naste]

I use my kolon dry film photoresist it work very good, i put it beside a pen as you know the result...

[chuckoo]

It all depends on what you want.

I have been using all these variants:

Photoresistive:  Best Quality, highest price of Material. Positiv20 .. NO..except you can spray without dust in air...
For the everyday user. If you use it seldom..results vary much

Milling: Highest Machiniery Price...but can be used for other stuff. Lowest Quality of traces. Fine traces impossible. Errors due to whiskers and the like are usual.

TTF: Very cheap ( few $ for a laminator ) . Even with some magazine papers one can achieve 10 mil traces and gaps. Blindingly fast. We have done boards from print to drilling in 10 Minutes !! Good reproducable as no material changes over time. Only the laminating time must be documented according to the paper used. With Press & Peel or Pulsar , very good results are usual. Free Magazine Paper works good also..but less easy to get away from boars again. Silkscreen can also be transferred onto board.

[Naste]

I often use toner transfer, but for best results, i use dry film photoresist from kolon.
You can see my project at www.nastelroy.wordpress.com

[HeliEye]

I design and produce 100's of PCB's in-house using fotoboard.  To transfer the image I use High resolution Jetstar Premium Inkjet film (A4 size) both from MegaUK.
I print at max res using Photo RPM on an Epson R200 printer.
I expose the film to the Fotobard using an RS components 4 tube UV box.
Most of my pcb's are SMT and some of the IC's extremely small footprints, the results are very good.
The hardest part is not getting fine enough resolution on the pcb, more the difficulty soldering such fine pitch components.
I use a Metcal MX5000 soldering station with 0.5mm tip for much of it.

Steve

[Biggles]

HeliEye, I used to use the Jetstar from Mega, but I switched to 3M clear transparency film (inkjet), type number:   CG3460   
I use the same film for pcb and gedakop artwork.

[HeliEye]

HeliEye, I used to use the Jetstar from Mega, but I switched to 3M clear transparency film (inkjet), type number:   CG3460  
I use the same film for pcb and gedakop artwork.

Ah thanks Biggles, I'll give that film a look. 
Does it give 'better' results than Jetstar Premium?
I'd be interested in your opinion on the 3M film.

Cheers

Steve

[Biggles]

I am not familiar with 'jetstar premium'..  all I had from mega at the time was 'jetstar'. (this was a few years ago I made the switch). I buy the 3M now from wherever I can get it cheapest, somtimes from a google search, even RS components and in the past have had good deals from Viking ( but not very often).

In my opinion, the 3M I use now is by far superior to the jetstar I used to use. The HP ink takes to the film very well. Blacks are BLACK (this can vary depending on the program!) , and very fine lines are not lost. Remember to select mirror print to prevent distortion through the film. The ink side must touch the material being exposed. (I like the HP printer interface.. as there are lots of options. ) Once printed, the film is very durable, I have printed transparencies I have been using for YEARS over and over again (mainly for gedakop as I have to do all that myself.)  I cant see myself looking elesewhere at other transparencies until I either have a supply problem getting the 3M or if I start getting problems with artwork.

[HeliEye]

Thanks Biggles for your insight :-)  Just out of interest, the 'Premium' Jetstar has a much finer surface, with higher resolution capabilities. I haven't tried the normal Jetstar.

I'll buy some of the 3M film and give it a whirl, many thanks again.. I'll report back when I've tried it out.

Cheers

Steve