Rapid Prototyping

[pyromaniac4382]

Oh right wax paper and a frozen dinner in the oven at 350 degrees Fahrenheit.

I was looking more from a re-usability stand point since I would not want to keep buying materials to make this whole system work. I guess it is better than toner transfer. That is the method I use for prototyping currently. Takes way too much time, and there are many points of failure throughout the entire process. If it is not toner transfer, I use ITead Studio since shipped it is about 30 bucks for 10 boards at 10cm by 10 cm.

 

[CarlosO]

The real advantage of the glue is that it doesn't need the heated curing,. This is what allow us to use paper and other thin films.

Heat is really not an issue given your substrate can take it, but I completely see the point for being able to de-solder something, which you can't do with the glue unless you actually break the bonding with a knife or something.

If I'm getting it right, you'd prefer to have something that applies solder paste, and then assembles the circuit? Then we would need to bake the circuit... The user could use an oven, or maybe the machine can do it at the end of the process.

So, how important is it to be able to use the machine in cheap materials like paper or thin films (transparency film)?

 

[pyromaniac4382]

I see value in, as I pointed out before, a complete at-home system. There are really only two methods that I have seen for at-home board fabrication, the toner transfer method, and the photo-litho method. While the toner transfer method is cheap it is not always accurate, and is prone to failure even under the best circumstances. Photolitho techniques require too many recurring costs. (pre-sensitized boards, light box, developer, transparency's, and so on.) The photo-litho is more accurate than the toner transfer method, but this accuracy costs.

From what has been said so far, a simple printer that could take your ink and print the circuit traces and pads directly onto a substrate would simplify at-home manufacturing. Glue, solder, whatever, if it means that I don't have to iron a board for half an hour I think it is a step in the right direction.

The substrate doesn't really matter to me when it comes down to it because more than likely I would be sending the design off to a board fab if it was correct, and worked as expected.

What your system would do is cut out the time it takes to prototype which is invaluable especially when you just want to see something work, and not wait x number of days to send the design out to a manufacturer and get it back just to find the prototype was a failure.

I see a need for a simpler method for at-home fabrication of boards, and all of these conductive inks are a great step in that direction.

 

[BobK]

From what has been said so far, a simple printer that could take your ink and print the circuit traces and pads directly onto a substrate would simplify at-manufacturing. Glue, solder, whatever, if it means that I don't have to iron a board for half an hour I think it is a step in the right direction.

I second this idea. If you could print resist onto FR4 with the same resolution as a laser printer I would fall in love. Extra points if the same machine could also drill the holes. However, $3000 is about 10X too high for hobbyists like me.

I use the photo-resist method and can make a board with about 75% success rate in an hour. There are reasonable cheap presensitized boards from China. I bought 5 10x15cm boards for $13.59 including shipping. Have not tried them out yet though.

Bob

 

[pyromaniac4382]

I think I have seen resist printed on copper-clad FR-4 with an altered laser printer. The problem with the method was there was not enough heat or pressure from the fuser to set the toner on the copper.

Another thing I just thought of since you said drills is through-hole components. Are those off the table?

 

[BobK]

Supposedly others have done so with an ink jet as well. You have to refill the ink cartridges with something that acts like resist.

Bob

 

[pyromaniac4382]

This project also looks very similar to this project.

https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print

 

[Arouse1973]

Yes its not new. I saw this sort of thing 10 years ago, but much more exspensive. One similar process was to mill small grooves in the PCB and then fill them with a silver paste to make tracks.

 

[pyromaniac4382]

Just a bit weary of how similar the demo circuits look in their projects. It may just be a coincidence.

 

[CarlosO]

Inkjet printing of circuits has been tried for a long time now. Last year Microsoft presented AgIC (the ones in the kickstarter above) and showed some circuits printed with that. By then we where halfway our first prototype, but we've come a long way since then.

The hardest part of printing circuits is providing a coherent environment for all the additional work required to assemble the board. We were trying to give an all-in-one solution, and we think that we're slowly getting there.

I've added some additional info on how the printer works and performs. Let me know if you have any additional questions.
http://www.botfactory.co/product

 

[(*steve*)]

Why can't someone (perhaps one of these AgCl printer people) find an ink that can be used in their printers that is also a resist?

Then I can use their AgCl to print up a board if I want it really quickly, or use the same printer to put the design onto copper. Seems like a minimal change in software and a doubling of utility for the device.

The existing use of inkjets for this is pretty poor because the ink doesn't dry quickly. Presumably this would require some sort of volatile solvent for the ink, and there's obviously issues with that.

The printing with wax idea (based on an epson cartridge) was excellent, but it seems to have gone nowhere.

Both of the above ideas require a piezo element rather than the thermal element that is more common today :-(

 

[CarlosO]

I think I have seen resist printed on copper-clad FR-4 with an altered laser printer. The problem with the method was there was not enough heat or pressure from the fuser to set the toner on the copper.

Another thing I just thought of since you said drills is through-hole components. Are those off the table?

Yep, kind of.
The real issue is, even when printing multi-layer boards, the ink is always facing up. If you drill holes and place a through-hole, you wont find any copper (conductive ink) at the bottom of the board.

This is a constrain for our technology, but on the other hand most through-hole components have an SMT version.

 

[CarlosO]

Just a bit weary of how similar the demo circuits look in their projects. It may just be a coincidence.

You're right.... . I guess I chose the wrong sample to post.... But hey! Its a Larsen Scanner, its cool, right!
I could probably post an arduino mini. I'll try that later today.

 

[CarlosO]

Why can't someone (perhaps one of these AgCl printer people) find an ink that can be used in their printers that is also a resist?

Then I can use their AgCl to print up a board if I want it really quickly, or use the same printer to put the design onto copper. Seems like a minimal change in software and a doubling of utility for the device.

The existing use of inkjets for this is pretty poor because the ink doesn't dry quickly. Presumably this would require some sort of volatile solvent for the ink, and there's obviously issues with that.

The printing with wax idea (based on an epson cartridge) was excellent, but it seems to have gone nowhere.

Both of the above ideas require a piezo element rather than the thermal element that is more common today :-(

So I have good and bad news. We're testing an ink that prints an insulating layer. We're using it to allow for multi-layer printing. It so happens that this ink may be resistant to the acid... The bad news is I'll have to get back to you on this because we're getting ready for our kickstarter and we don't have that much time now.

Carlos

 

[pyromaniac4382]

Well hybrid SMD and Through-Hole would work with one layer. Your SMD would go on trace side, and through-hole would go through top-side to trace-side, hard to design for, but do-able. I have seen fancy board layouts achieve this to jump gaps, and simplify layout. It is like sudo-double-sided. The drills would always go to trace-side donut pads.

 

[CarlosO]

Hello Everyone,
Just wanted to tell you we're planning to go for crowdfunding soon.

If its not too much to ask, would you mind supporting us by allowing us to post ONE message on your facebook wall? It would allow us to create a synchronized wave of posts the day of launching our campaign. You just need to go to this link and click the facebook button:

http://thunderclap.it/projects/13377-squink-your-circuit-factory

Thanks so much for your time and help. Your feedback is invaluable.

 

[davenn]

the forum doesn't have a facebook page

 

[CarlosO]

the forum doesn't have a facebook page

Check!
I was thinking more on the people that contributed to this conversation.
Thanks for your reply!

 

[(*steve*)]

Sorry Carlos, I don't have a facebook page either.

I appreciate the good and bad news above. I also appreciate that you're under pressure for the crowd funding thing.

If you get time to spray on your insulating ink onto copper and try etching I'd be really interested.

Gee, if you send me a small piece of board with the ink on it in any sort of pattern I'll etch it for you and report back.

Best of luck with the crowd funding and thanks a lot for putting in the time to answer our questions.

Note that it would be considered spam for you to post your crowd funding link unless someone asks you for it.

So, where can I see your crowd funding project?

 

[CarlosO]

Sorry Carlos, I don't have a facebook page either.

I appreciate the good and bad news above. I also appreciate that you're under pressure for the crowd funding thing.

If you get time to spray on your insulating ink onto copper and try etching I'd be really interested.

Gee, if you send me a small piece of board with the ink on it in any sort of pattern I'll etch it for you and report back.

Best of luck with the crowd funding and thanks a lot for putting in the time to answer our questions.

Note that it would be considered spam for you to post your crowd funding link unless someone asks you for it.

So, where can I see your crowd funding project?

Thanks for your support Steve.
Let me find a moment next week and I'll try to do the tests with the insulating layer. I'll get back to you on this.

Regarding the Kickstarter, we just launched! You can find some more info here:
https://www.kickstarter.com/projects/botfactory/squink-the-personal-electronic-circuit-factory

All the best,

Carlos