Handwritten Circuits

A regular ball point type pen that can write conductive pathways for designing circuits.

http://www.gizmag.com/silver-pen-for-handwriting-electrical-circuits/19059/

I'm going to do a short run of origami green pres for those who are interested. I'm working out a price right now. Question: Blotter paper or Construction?


But seriously, prototyping couldn't be easier.

It may be conductive, but if it has any kind of resistance - it could be troublesome.

LOL!!! I have to say that is really old hat. I printed circuits with flashing LEDs on a coke can back in the 80's. I even printed the same circuit on the front cover of Electronics Weekly, framed it and sent it to the editor. It got me a piece on 3D circuits in a later issue.

Cheers

Ian

Wow, that is an extreme case of an academic with their head in the sand (or somewhere else).

US Patent 1,034,104 describes a silver ink dispensed from a pen (patent granted July 30, 1912).  Good work U of I, you're only 99 years late.

Back in the '70s I made a hand drawn circuit board, by drawing the conductors pattern I wanted to keep on copper clad with some tooling ink, and etching off what I didn't... fast and dirty... but it worked and was quick.  I only did it once, tho...

JR

JohnRoberts said:

Back in the '70s I made a hand drawn circuit board, by drawing the conductors pattern I wanted to keep on copper clad with some tooling ink, and etching off what I didn't... fast and dirty... but it worked and was quick.  I only did it once, tho...

JR

Click to expand...

You used to be able to buy an etch resistant marker pen - called the Dalo pen if memory serves.

Cheers


Ian

ruffrecords said:

JohnRoberts said:

Back in the '70s I made a hand drawn circuit board, by drawing the conductors pattern I wanted to keep on copper clad with some tooling ink, and etching off what I didn't... fast and dirty... but it worked and was quick.  I only did it once, tho...

JR

Click to expand...

You used to be able to buy an etch resistant marker pen - called the Dalo pen if memory serves.

Cheers


Ian

Click to expand...

I don't recall seeing any back in the '70s and I didn't think it was a good enough idea to repeat, or refine.

JR

I've always known them as "trace repair" pens.

JohnRoberts said:

ruffrecords said:

JohnRoberts said:

Back in the '70s I made a hand drawn circuit board, by drawing the conductors pattern I wanted to keep on copper clad with some tooling ink, and etching off what I didn't... fast and dirty... but it worked and was quick.  I only did it once, tho...

JR

Click to expand...

You used to be able to buy an etch resistant marker pen - called the Dalo pen if memory serves.

Cheers


Ian

Click to expand...

I don't recall seeing any back in the '70s and I didn't think it was a good enough idea to repeat, or refine.

JR

Click to expand...

Ian is 100% right and Dalo was exactly the name and was indeed available since the early 70's at least.
Lord knows how many boards that shaped the world we live in today, have been etched with those very pens which are
available still today: http://www.peats.com/cgi-bin/catalog_v2.cgi?id=6241&type=product

I will never forget the first boards I ever made with those as a kid.

I wish I would have known to ask you guys back then...

I was mostly using copy cameras to reduce oversized artwork down to make 1x negatives, and then using photographic process (KPR or something like that), to expose and cure a resist on copper clad, befopre etching with mostly ferric chloride. But even then I didn't make many 1X of anything.

By the mid '70s I discovered I could pay people to make PCBs.

JR

V9977 said:

Ian is 100% right and Dalo was exactly the name and was indeed available since the early 70's at least.
Lord knows how many boards that shaped the world we live in today, have been etched with those very pens which are
available still today: http://www.peats.com/cgi-bin/catalog_v2.cgi?id=6241&type=product

I will never forget the first boards I ever made with those as a kid.

Click to expand...

Still available in the UK too:

http://www.maplin.co.uk/dalo-etch-resist-marker-pen-2105

Cheers

Ian

A Sharpie sorta works as etch-resist. Done several boards that way.

Conductive ink in pens is very old.

Auto-parts store has "defroster repair" which can be built up to take substantial current.

An issue is that such inks may not be solderable.

What would be cool would be to develop a substance that could be ink-jetted onto bare fr4, that would attract copper in a plating bath, much like they do for nickel plated(chromed) plastic parts, like on cars. Then you would only use the copper you need, rather than plating the entire board and then wasting the unused copper. The tough part would be durability during soldering I guess.

PRR said:

An issue is that such inks may not be solderable.

Click to expand...

Indeed. The ones I used back in the 80s were silver loaded  epoxy based so you literally glued the circuit together with the interconnect.

Cheers

Ian

gemini86 said:

What would be cool would be to develop a substance that could be ink-jetted onto bare fr4, that would attract copper in a plating bath, much like they do for nickel plated(chromed) plastic parts, like on cars. Then you would only use the copper you need, rather than plating the entire board and then wasting the unused copper. The tough part would be durability during soldering I guess.

Click to expand...

That has been more or less available for some time, until they realised that when you do ground planes, it becomes pointless. I think it was dubbed "positive-etch".