Flex PCBs

[Alex]

Hi all,

I am putting together a project that requires a flexible PCB. I am planning to use polyimide film coated with copper, the standard way of doing it.

I was wondering if you are aware of any supplier or shop that stocks this material (or similar) and that I can access from the UK. The exact dimensions and specifications are not critical, but I only need an A4-sized sheet or so.

If you have made a flexible PCB using a different material then please, do share.

Thanks

[mikeselectricstuff]

Farnell sell this photoresist flex PCB

[Alex]

Many thanks Mike!

[mikeselectricstuff]

Better double check - looking again it appears this isn't presensitised - the picture shows a peel-off film, but the data refers to it as 'raw'.
I have some stuff I bought a long while ago, which to add to the confusion is photoresist but does not have a peel-off film.

[Alex]

It doesnt matter, I can other coat it myself or use e.g. the toner transfer method.

[TheDirty]

What do you mean by flexible?

You can use this copper clad, if you just want to bend the board around something.
http://www.goldmine-elec-products.com/prodinfo.asp?number=G17455

If you want the PCB to be able to flex multiple times and not break, like a commercial FPC, then I have no idea how you would approach that hobby wise.

[Alex]

By flexible I mean a circuit board that can bend to a radius of 3cm about 100 times during its lifetime without being damaged.

Thats an interesting approach, a bit worried that it would be fragile.

Flex boards are normally made with polyimide film commercially.

[JohnS_AZ]

I don't know how fancy you need to be, but in the past I've built prototypes using the flex material that connects the print head to it's drivers from trashed dot matrix printers.

[Alex]

How did you make your own circuit though? That flex pcb is just the equivalent of a flat ribbon cable. I am looking to etch a custom pcb design.
The CIF flex protoboard material that mike suggested and the Dupornt protoboard material that I also found are the equiavent of a 'blank' copper clad board.

[mikeselectricstuff]

I just rememembered where  I got some photoresist flex from : Mega, who  incidentally are good for pretty much any PCB-making supplies.

[Alex]

Thanks Mike, a similar price to the product on Farnell.

[Zero999]

Farnell sell this photoresist flex PCB

It's very expensive though.

[Alex]

The Mega and Farnell SS boards are of a similar price. I have got a SS sheet from Farnell to try it out.

[mikeselectricstuff]

Can you confirm that the Farnell's stuff is not photoresist coated?
The Mega stuff definitely is.

[Zero999]

Have you tried Farnell technical support?

[mikeselectricstuff]

Have you tried Farnell technical support?

Excuse my scepticism based  on the sometimes patchy  info on teh Farnell website but I would sooner trust info from someone who actually has it in their hand....

[Alex]

It turns out the CIF product on Farnell is without photoresistive coating, just a peelable cover on the copper.

The product on Mega is 3 times bigger than the one on Farnell for the same price, and it has photoresistive coating which can be removed if one is to use the toner or solid ink processes.