PCB Image Transfer Light Box

[Suraj143]

Hi guys all the time I’m using toner transfer method to make my PCBs. It worked well for me.

In toner transfer method I’m using the IRON to transfer the image to the PCB.

Is there any other method to transfer the image to the PCB with a light box?

What is a light box?
Can I make at home?
I don’t have UV lights I have only FLUORESCENT bulbs & also I don’t have special chemical I have only ferric chloride.

Thanks

 

[Robot builder 101]

Google does wonders!

(in case you diddn't get it, google for it, then ask)

 

[monkeybiter]

i use a vintage 'ultraphil' uv spot bulb at 11", no dark room or light box. in tests it also exposed ok with a 100w ordinary household spot, but it took nearly 4 hours!
inkjet print design onto inkjet transparency paper [for overhead projectors].
expose onto presensitised copper clad board.
develop in caustic solution at room temp. [too strong will wash the lot off!]
etch in ferric chloride or sodium persulphate at 40'-60'c
it's easier than it sounds. be prepared to ruin a couple of boards getting it right

 

[Suraj143]

Oh thanks a lot monkeybiter

I was thinking what paper to use. Now I planned to take projector papers (transparent sheets)
Can I use old magazine papers?

1) I will keep the copper board in the bottom of the box keeping copper side upwards.
2) After I take the printout & keeping on the copper board placing the printed side downwards touching the copper board.

3) After that I switch on the lights for couple of hours keeping the box close.

Is this right?

 

[monkeybiter]

presensitised means the copper surface is coated with a layer of photosensitive material.
your printed layout must be on transparent 'paper'.
when you lay the printed transparency on the sensitised surface of the board, [after peeling off any protective layer], you then expose the board through the transparency.
where there is ink on the transparency, the board is not exposed to the light. where there are gaps, the board is exposed.
when you develop the board, the exposed areas are washed away, the unexposed areas that were under the ink are left intact.
after washing in water, etch the developed board in the etchant of choice/availability. the exposed areas will have the copper completely etched away, the areas shielded by the ink on the transparency will remain.

magazine paper is sometimes used in the 'toner transfer' method, using laser printer or photocopier.

 

[Suraj143]

Thanks a lot monkeybiter now I understood.

I heard that there is something called inkjet printer & film.

what is the meaning of film is that the transparent paper?

Now the problem is to find photosensitive material.No more place to buy.

 

[Robot builder 101]

magazine paper works well too. Just use an iron on the reverse side (side with ink facing board) and press down on it very hard with a iron, making it cook into the board. Do this with lots of pressure for like 2 min. Then drop into boiling water to rid of paper. Then etch.

 

[monkeybiter]

as i indicated, magazine paper is used sometimes in the 'toner transfer' method. suraj is asking about the photo method.

transparent film for inkjet printers is the right stuff. be sure to print on the correct side. during exposure i recommend a thin sheet of glass [from a photo frame perhaps] on top of the transparency to stop it curling with the heat.
re. photosensitive material, you can buy aerosol cans of the stuff to spray on a plain copper clad board, but i think this may be more expensive.

 

[Suraj143]

Ok thanks a lot guys I 'll try to find photosensitive material.

Now I understood.When exposing with a light source it really needs a photosensitive material.Otherwise cant do.

Its done by exposing & leaving the some photosensitive material on the PCB by the mask layer.
The remaining photosensitive material will be still there after etching with ferric chloride.

 

[3v0]

If you are unhappy with the results you get from magazine paper and a clothes iron you should try real transfer paper (pulsarPro or Press&Peel Blue) and a laminator. At least try the trick where you put a wood dowel under the board while ironing to simulate a laminator. (see pulsarProFx.com site)