helpful pen to repair broken traces (maybe...)

hi all,

I've read about this pen:
http://www.bareconductive.com/store
it seems good also to repair broken traces and, I suppose, to make jumpers on existing traces (if they're masked).

I didn't buy it yet so I can't tell you if it's good or not.

Maybe somebody of you could need it in the future, or somebody already tried it or, also, somebody knows a similar product... ?

-- Giovi

The "ink" looks to be rather thick--I think that it would be very difficult to repair a fine thin trace using it.

Copper and silver-dispensing pens are the usual tools

But personally, I prefer 30 AWG Kynar-insulated wire. If both ends are well-soldered to the PCB traces, you don't doubt that the wire conducts from one end to the other. With a pen, you can never be quite certain.

I'm interested in the claim that it can also be used as a conductive glue. I'm thinking of when you want to replace a small SMD capacitor and soldering is a pain. A pin-load of conductive glue could be attractive, if it could be trusted under moderate heat load.

Fine traces are difficult with the trace pens, as well. I've found it works best to just make sure you have plenty in place, then come back when it is dry and trim back with the point of a blade or a dental pick.

One limitation of polymer trace pens is that you can't test continuity until it has dried.

Rick

I've thought of the conductive glue to be a candidate for attaching wire leads to battery cases, in lieu of soldering or spot-welding.

I note that the description of the black goo doesn't give any sort of figure for resistance after drying.

I've used a conductive pen to repair a fine trace, by masking the spot where the trace is broken with painter's tape, then peeling it off when the ink dries. It worked pretty well, but if I have a choice, I'll still use fine wire.

Chuck(G) said:

I note that the description of the black goo doesn't give any sort of figure for resistance after drying.

Click to expand...

There's quite some detail on resistivity in this technical datasheet.

They suggest use as a paint-on potentiometer, so resistance is clearly more significant than metal. The stuff is advertised as water-soluble, so I'm guessing it is some mixture of carbon black and a black metal oxide in a PVA base.

Suggested screen-printing of circuits looks an interesting option for prototyping small projects.

This particular solution is obviously going to be too viscous for inkjet printing, but a similar formulation might be made compatible with 3D printer nozzles (used in 2D operation, for circuits). Or somebody might design a purposed inkjet with a suitable nozzle configuration for circuit printing on flexible materials.

One limitation there is that anything PVA based is not going to be compatible with any sort of soldering or significant operational heat.

Rick

Chuck(G) said:

I note that the description of the black goo doesn't give any sort of figure for resistance after drying.

Click to expand...

There's quite some detail on resistivity in this technical datasheet.

They suggest use as a paint-on potentiometer, so resistance is clearly more significant than metal. The stuff is advertised as water-soluble, so I'm guessing it is some mixture of carbon black and a black metal oxide in a PVA base.

Suggested screen-printing of circuits looks an interesting option for prototyping small projects.

This particular solution is obviously going to be too viscous for inkjet printing, but a similar formulation might be made compatible with 3D printer nozzles (used in 2D operation, for circuits). Or somebody might design a purposed inkjet with a suitable nozzle configuration for circuit printing on flexible materials.

One limitation there is that anything PVA based is not going to be compatible with any sort of soldering or significant operational heat.

Rick

RickNel said:

This particular solution is obviously going to be too viscous for inkjet printing, but a similar formulation might be made compatible with 3D printer nozzles (used in 2D operation, for circuits). Or somebody might design a purposed inkjet with a suitable nozzle configuration for circuit printing on flexible materials.

Click to expand...

I'm dreaming about the day somebody will invent an ink jet printer that print also component: transistor, diodes, resistors, capacitors... I think it will be possible in a (not too) far future... something like EAGLE -> board design -> menu "file" -> "print" -> "print pcb" -> Epson Stylus PCB

couldn't you sort of do this already with a 3d printer, granted you'd have to trace the circuits and such, and insert the metal pins for the slots by hand, but couldn't designing and printing a pcb *double sided through hole only* be possible already? Hell, you can print food, why not computer parts too?

giobbi said:

I'm dreaming about the day somebody will invent an ink jet printer that print also component: transistor, diodes, resistors, capacitors... I think it will be possible in a (not too) far future... something like EAGLE -> board design -> menu "file" -> "print" -> "print pcb" -> Epson Stylus PCB

Click to expand...

Investigate how transistors are manufactured--that should answer your question about why it isn't done.

Chuck(G) said:

Investigate how transistors are manufactured--that should answer your question about why it isn't done.

Click to expand...

of course you're actually right, but "it can't be done" usually means "it can't be done...yet"

I've not heard of 3D printers that can work with more than one material at a time (yet), but we are quite accustomed to inkjets that can squirt from multiple nozzles, so multi-layer circuit printing and some simple component printing (resistors, capacitors, inductors, diodes) may not be so far-fetched. Printed capacitors are already around in the plastic membranes of some keyboards and touchscreens. Can't see it in nano-scale ICs anytime soon, though.

Rick

There's been talk/news about circuits made from pencils (lead = conductive). A Commodore 1520 might be able to do something like that (or any plotter). Alternatively if the metal stays in liquid form you could probably print using it then use some other "color" (r(y/g)b) masking agent to create layers. But yeah could be quite an inefficient way to do things. Alternatively though I suppose you could possibly print something on to pcb and etch a board too. One guy in the robot group did a powwow at his place on diy pcboard etching at home that I unfortunately missed.

Thick film circuits are basically printed circuitry using conductive epoxy. Typically it is silk screened. Conductors, resistors and dielectrics can be printed. Each layer is screened on, then cured. This same kind of process could no doubt be done by some kind of printer.

Google "printable transistors" and you will find that they exist now, but mostly just in the laboratory.

If you consider thin film transistors, as in TFT display, as printable transistors, then they are in production.

You actually can print an integrated circuit with e-beam lithography. One problem with this is that it prints each gate one-by-one, so it takes a long time to print one mask layer.

I can still remember a friend of mine, back in the '80s, looking at my 300 baud modem and telling me "maybe one day we'll be able to transfer the content of some floppy disks using just a modem!" ...and I told him, "hhmm, maybe in a far future, who knows? ...but probably not..."

Technology runs fast, and what seems impossible today, will be normal in the future.
Did anybody imagine internet in the '80s? Did anybody in the '90s predict its evolution in 20 years?
How about 2 Tb hard disk...do you remember our 20 Mb hard disks in the '80s?
MP3, Blu-Ray, smartphone, gps, internet mobile...
I think 3D printers are just in a jurassic stage, they're just prototypes; in the next ten or fifteen years they will change so much that they will change our live forever. Printing electronics devices will be just one aspect. We'll print everything we need, or almost all.

(the funny part is: if I'm right, you will remember my prophecy and will tell to your nephews: "there was a man, once upon a time, that predicted all of that...."; while if I'm wrong you certainly will not remember this silly post )

-- Giovi the wise man ;-)

We had the internet in the 70s, we just didn't call it that. (ARPAnet, USENET, etc.). I still have my "internet starter kit" for the PC--it didn't include a browser (the web wasn't around yet), but there were mail clients, telnet, ftp, uucp, etc.

I have used a Bryant 4000.





I'm looking at a Shugart SA4004 hard disk as I type this on a 1999-era HP E-PC running Windows 2K.

Have we made much progress, technically, since, say, 2000? Is real technical advancement slowing down and just devolving into variations?

The 1990s brought in the web, the 80s popularized the PC and the 70s brought in the microprocessor. The 60s brought in modems and important advances in computer architecture.