Inexpensive Prototype Circuit Board Fabrication

So I should retire that Radio Shack Etching solution that I've been storing for 25 years? 

What software do you draw your boards with?  I always marvel at how fast you put these together.

Bob

Excellent find John. Funny that their headquarters are less than 10 minutes from where I live and I haven't heard about them. Where did you happen to run into them?

123Design Circuits

I use DipTrace for my board layouts.  I found it was easy to bring it up, and their component editor was way easier to figure out as opposed to Eagle PCB, that one is a PITA!  Once you have done a few boards, they come together pretty fast.  One key for me was to develop a library of commonly used parts and store them in a custom library.  That way I can modify the footprint if there isn't a proper one, and I can find my common parts very quickly.  I also try to use common parts over and over, even if there might be a "better" choice for a particular application.  Case in point is I use a 1A diode a lot, even though sometimes I only need a 10-15ma diode.  It's just more convenient to have common parts if there's not an overriding reason not to.  I did add a smaller diode to my mix recently as I really needed one.  I also use common sized resistors, usually either 0603 or 0805 footprint.

enginEErjon posted:

Excellent find John. Funny that their headquarters are less than 10 minutes from where I live and I haven't heard about them. Where did you happen to run into them?

Someone on another forum mentioned them to me, when I looked, I was impressed.

AlanRail posted:

123Design Circuits

Are you talking about AutoDesk?  That's not a PCB assembly house, it's a design package.  As far as PCB design, IMO not in the same league as the other design packages.  Doing all of this on-line doesn't appeal to me at all. 

This could be a game-changer for the OGR community.  There have been countless "simple" circuits discussed in this forum that only require a handful of components...or circuits that need to fit in an engine or rolling stock and hence require interconnecting surface mount components which generally means a printed-circuit board.   No for-profit enterprise would touch these circuits because of the low volume. 

Sure, someone needs to generate the Gerber-drill files using a design program but as GRJ shows there are low-cost or freeware programs especially if you're designing small/simple circuit boards.

This service removes the one-time set-up cost barrier which in my mind has been in the $30-50 range.  For building a handful of small boards, it has been impossible to get the per-board cost down to, say, $1.  What I've done in the past was gather up multiple designs, often from friends who also were in the same situation, and fabricate a single board that has multiple designs on it...essentially a tedious and laborious process but what the OSH Park folks seem to have automated.

I dug out this old board showing 25 or so different boards (manually cut apart ) consisting of a half-dozen different circuits (a few of each) that got the out-of-pocket cost down to $1 per board.  Remember that labor is "free" in a hobby!

That is doing it the hard way Stan!  The other thing I like is the silk screen and solder mask both sides.  Also, you can get complex board shapes for the same price, it really almost looks too good to be true.

There is a learning curve for any PCB package, but once you climb that mountain, you can crank out a new board pretty quickly, especially for the small boards I typically deal with.

gunrunnerjohn posted:

That is doing it the hard way Stan! 

Tell me about it! That's exactly why your find is, as you say, almost too good to be true!

I don't know if still done today, but then there were the fab houses that would examine your Gerbers for evidence of multiple designs and nix them to get the teaser pricing.

Anyway, it would be interesting if a library of Gerber-drill files of a dozen or so designs could get posted here so anyone could pony up $5 to get a handful of bare boards.  While most guys seem to want assembled/tested boards, it seems DigiKey comes up often enough that some guys have the time/ability to muck around at the component level.

Well, I started the library with the DCS-RC WD Timer Board.

BTW, what PCB package do you use?

Moving right along, faster than I figured.  Just got this email.  I'm stunned they do that large a panel, I'd like to see that process in action! I can start to see where the economy of scale kicks in, I didn't think they'd make panels nearly that large.

I'm still impressed.

==============================================================================================

Your boards are being made as you read this!

We've sent the panel containing your boards to the fabricator. We expect to get them back around October 7th.

In case you're interested, there are 52 other orders on the panel along with yours, adding up to a total of 264 boards. Neat eh?

I love building boards and coming up with solutions. Although you guys are way above my technical expertise I can get buy on the board building and have a few EE friends to help me out but there just aren't enough hours in the day reinvent the wheel every time.

stan2004 posted:

gunrunnerjohn posted:

That is doing it the hard way Stan! 

Tell me about it! That's exactly why your find is, as you say, almost too good to be true!

I don't know if still done today, but then there were the fab houses that would examine your Gerbers for evidence of multiple designs and nix them to get the teaser pricing.

Anyway, it would be interesting if a library of Gerber-drill files of a dozen or so designs could get posted here so anyone could pony up $5 to get a handful of bare boards.  While most guys seem to want assembled/tested boards, it seems DigiKey comes up often enough that some guys have the time/ability to muck around at the component level.

This sounds like a very good idea. I probably won't be doing any design, but it sure would be neat to have the board files available for different projects we could make. Hopefully you knowledgeable folks would also post a parts list, say from Digi-Key, that us green horns could use to populate our boards.  

GRJ's newly found fabrication house would be the place to go and the costs sound extremely reasonable to me. Not that I know what any others would cost, but his posted prices above look very inexpensive.

I would certainly be interested in using something that was posted. 

I was designing PC boards before we had multi-layer plated thru holes. Can anybody guess how we got around the lack of a plate thru hole to connect the two layers?

To keep focus and not descend into a my program is better than your program free-for-all, I downloaded and started messing with the program GRJ mentioned above.  In addition to sharing the ready-to-order printed-wire-board files (aka Gerbers), I see benefits to sharing component libraries and even the schematic files as many O-gauge circuits are remarkably similar requiring the same functionality/parts....such as AC-to-DC conversion, a filter capacitor, a DCS inductor, a relay driven by a transistor with a clamp diode, a screw-terminal strip, etc. 

Let the games begin!

I have modified and added a number of components and patterns, especially for unique stuff like some of the opto-couplers I use.  Here's an example of some of the stuff you run into when you do the PCB designs. 

When doing the DCS-RC WD circuit submission for OSH Park, I found out that the DipTrace transistor footprint didn't meet their design criteria, so I had to modify it.  They want a 7 mil annular ring around any plated hole, none of the DipTrace patterns had that.  the standard TO-92 pattern couldn't be made to work, there wasn't enough lead spacing!  I ended up using an alternate footprint, and then modifying the one square pad to a octagon so it had at least 7mil.

This one wouldn't work at all, and there wasn't enough room to modify it.

This one didn't have the proper annular ring, and increasing the size of the square pad ran into the other pads.

I ended up with this pattern, I can still identify the #1 lead, but it meets their design criteria.

I probably can't design a PCB, but I can make lists of files and projects with links. I would be happy to start a thread in the Electrical Manuals and Info 'Sticky' area and try to keep the files and info in a somewhat organized manner. That is if you are all agreeable. If you think another forum or area would be better that is good too. At least I would sort of feel like I was doing something to help the folks doing all the heavy lifting.

I was thinking of maybe putting the list in the first post of a thread. Everyone could post their projects to the same thread and I could update the top thread as needed. Or something along those lines anyway. Might keep things all in one place and easier to find. Let me know what you all think.

You might ask Rich to pin the topic, that would help insure we could find it.

I will put something together and post here for comments. Then I will ask Rich about that.

Does every one think the Electrical forum is the best place for this?

So far I was thinking of a brief description of the purpose for each board, a parts list (hopefully all from Digi-Key) and the Gerber file(s). Of course your PCB maker's info would be at the beginning of the post and maybe a brief explanation of that as well. I would also list Diptrace as the PCB design program and include any libraries that folks might post. Maybe a two or three part list would be better, a part for each of the 2 programs and one for the Gerber files themselves.

Well, it is certainly electrical, so this seems like the best place!

A recommendation:  Don't get "carried away" with the "requirements" for posting the files, or you won't get much.  This "service" would be for the tinkerer, and if they have detailed questions, the person that posted the design can probably answer them.

You don't have to have DipTrace as your layout package, virtually any layout package can generate Gerber and NC/Drill files, which is what the folks at OSH Park want for their process, for instance.  Most other PCB makers would want the same files. 

As far as the information on the PCB fabrication house, I think it would be better to simply list a few of the cheap prototype board houses and let the person building the board pick their poison.  Some of the PCB houses may have different design requirements or constraints, so my plan would be to actually specify where I got boards made for a specific project, although there's no requirement that others would have to use the same vendor.

My view is this will be a fairly informal thing and grow as time goes on.

GRJ, I appreciate your comments, always good to get information from those that know what they are doing.

I wasn't meaning to have requirements for posting the files or anything like that. And yes they the file users would definitely need to go to the file creator for questions as I don't think I could answer any of them? I was going to include the file designer to give them proper credit for their work. 

My thinking was going along the lines of what Stan posted about the inexpensive boards at the place you listed in this thread and his thoughts on sharing the files and libraries. Kind of like the PTC list I made from you and others input on them (that probably no one has used since?  . It sounded to me like Stan was looking at DipTrace for compatibility with your files and libraries so as not to complicate things. I get your point on other programs though and maybe not all folks would be using the same design program. The Nuts & Volts magazine I read seems to like that Eagle PCB program that you didn't like. I will give that one some more thought.

I would be happy to add more PCB fabrication houses, if you wouldn't mind assisting. The one you posted here is the only thing I know about them and have absolutely no experience with anything like this. I do think that's a good idea to have options. I was thinking more along the lines of green horns like me wanting to tinker that would be relying on the recommendations from others as to where to get the PCBs made.

I also agree with the informal part and I certainly do hope it grows over time. I really think it would be a good way for folks to learn. I didn't want to make standards or anything, I was just thinking it would be nice to have the projects all in one place in a somewhat organized list or thread that would be easy to find. There are so many things here that I have seen that I might like to try someday and then a year later I can't find them again or forget completely. I save some things on my computer, but sometimes finding that stuff is about like searching here sometimes.

All comments, ideas and assistance welcome. 

rtr12 posted:

It sounded to me like Stan was looking at DipTrace for compatibility with your files and libraries so as not to complicate things. I get your point on other programs though and maybe not all folks would be using the same design program.

It's a good point about the libraries, those would be specific to a design program.

rtr12 posted:

The Nuts & Volts magazine I read seems to like that Eagle PCB program that you didn't like. I will give that one some more thought.

I may have been having a bad hair day when I tried Eagle, but the component creation seemed inordinately complex.  After struggling to make a simple component and pattern, I decided to expand my search for a PCB layout application.  If you do any amount of PCB work, you'll find yourself making quite a few new components and patterns, so ease of use of those functions is very high on my list.  Eagle seemed fine generating the schematic, that went fine.  Even creating the board was not an issue, it was just making new parts.

rtr12 posted:

I would be happy to add more PCB fabrication houses, if you wouldn't mind assisting. The one you posted here is the only thing I know about them and have absolutely no experience with anything like this. I do think that's a good idea to have options. I was thinking more along the lines of green horns like me wanting to tinker that would be relying on the recommendations from others as to where to get the PCBs made.

Well, I would only post about PCB fabrication places that I actually had experience with.  I'm expecting that my experience with OSH Park will be good based on how responsive they were to questions, and the smoothness of the ordering process.  Obviously, I've done a lot with Bay Area Circuits, and I have no complaints about the service or product.

Ok, I think to start I will stick with DipTrace and what ever libraries you folks are willing to share. More can be added later if there is a need for them. Maybe Stan will weigh in with his thoughts on DipTrace, libraries, PCBs, etc. I was hoping he would. He's probably busy, off designing PCBs right now as we type... 

For the list of everything else, I think I will just wait for your opinion on the OSH Park PCBs and then include them and the Bay Area place you have used. If other folks see the list they can comment on any of the places they like and I can add them later. Not that I know anything, but I think the OSH Park prices are very good as you have stated earlier. as you say, they may be hard to beat? Sure sounds cheap to me with what little I know.

I've been mulling this over and in the keeping-the-eye-on-the-prize category, the prize is purchasing a few boards at $1 per sq. inch.  The OSH Park site has Shared Projects which lists thousands of different board designs made by their community with a clickable link to order a board.  Today alone, half a dozen designs have already been uploaded.  For example, here's a small board about the size of my hand-wired Perpetual Barking Watchdog (PBW); one has to register on the site but by clicking on the Order link it appears in a matter of a few clicks one gets 3 bare boards for $2.40 shipped.  That's the prize! 

To be sure, this is a discussion...presently with only a few participants...but it seems for the simple circuits I'm imagining the choice of design tools, sharing libraries, is all fine and well but is a distraction.  I believe the average guy just wants to know the link to order a bare-board in the same way one asks for a link to a DigiKey part or a link to an eBay listing.

I have no conclusions on how to proceed but am very interested in additional viewpoints.

One of the issues with a vast majority of the shared designs on OSH Park is I don't see any description of what many of them do, and the title is non-illuminating.  If I were going to build something, I'd also like a schematic, parts list, etc.  Only a handful actually have enough documentation to make the board useful.

I also get a charge of some of the shared boards.    Arduino ICT Probe 8080 V1.00  Really?  Is anyone designing anything with the 8080 in this century?

Thanks for the comments Stan. After reading your post I am now thinking of just a list of projects with files to make the PCBs. I think it would be nice to have the PCB files here to download, but the OSH Park shared list looks like they would be very easy to order or download from there, so posting files there and having a link here might be a good idea too. This could be an 'and/or' where both might be good to have? I think I kind of like the 'both' idea myself. I noticed OSH has 'permalinks' just like the OGR forum so a link should go right to the project there.

The other thing I think should be included here is a description of the PCBs purpose, a schematic and a parts list (hopefully with Digi-Key part numbers) so the 'green horns' like me could easily use the PCB project files to get the boards made and also get the correct parts to go with them. The schematic would help with learning, using it to help understand how the circuit works. Then as GRJ stated above any questions could be referred to the original PCB designer. 

From GRJ's comments, yours included, I am now thinking I could just put a blurb about DipTrace at the end of the list and add any library contributions there with a short description of what they are for and what they do. Maybe something like that anyway. We could also list some other PCB fabricators as options there as well. I guess the design files would also have to be here in that case, but could still be at OSH.

Again, still thinking out loud here and any further comments (good or bad), advice, ideas are welcome.

GRJ, you posted while I was typing, but I certainly agree on your observation of the OSH shared list. I couldn't figure out what many of the items were or their functions? We definitely need the schematics, parts lists and descriptions here.

rtr12 posted:

... I think I kind of like the 'both' idea myself. I noticed OSH has 'permalinks' just like the OGR forum so a link should go right to the project there.

The other thing I think should be included here is a description of the PCBs purpose, a schematic and a parts list (hopefully with Digi-Key part numbers) so the 'green horns' like me could easily use the PCB project files to get the boards made and also get the correct parts to go with them. The schematic would help with learning, using it to help understand how the circuit works. Then as GRJ stated above any questions could be referred to the original PCB designer. 

Not sure where this takes us. 

I saw a few projects that did have enough information to make them useful.  I suspect maybe if you share your PCB, you can then use the Perma-link to link to it from a forum like this to let people know where to find it.

Stan's OSH project link above was quite detailed, schematic and all. I especially liked the Digi-Key shopping list. It's the best listing I have seen there, but I haven't yet looked around on OSH all that much. I still think it might be nice to have the info listed here on the OGR forum, that is if anyone else still thinks it's a good idea? On the other hand I am also thinking about Stan's last comment about not being sure where this takes us now with the info possibly all being on the OSH site? And to also steal one more of Stan's lines, "I am still on the case", that is if anyone is still interested... 

I think at a minimum we would have a place to describe the projects.  Most folks that might be interested in a turn-key project won't look on the OSH Park site, and they'd have to wade through all the noise of projects that are not defined, and not of any interest to them, to figure out if there was anything they could use there.  Having the boards up on OSH Park for easy ordering is fine, but there should be links here as well.

That's pretty much the direction I was leaning as well. I will start a list for posting here on the OGR forum and we will see where it goes. That would narrow things down to just the train type projects the folks here would be using. I agree, the project list on OSH was quite long and some descriptions very brief that probably only you and Stan and few others would understand. OSH could be like looking for a needle in a haystack, or like finding an old thread here that you know is here, but the search words are way too common. 

You mean "train" or "MTH" or "Lionel" won't get you right to the post you are looking for?

When the dust settles, it may be that we simply thank GRJ for his discovery and bringing it to our attention...knowledge is power, the truth will set you free, etc..

I've been thinking about several circuits discussed on OGR that required working at the component-level and soldering to perform some train-related function.  It's hard to make generalizations but that said, I think the overwhelming majority of guys want plug-and-play solutions.  Being able to order a bare circuit board is great but there are still additional steps to get to plug-and-play.

I only speak for myself but in recent years pretty much all boards I've fabricated use surface-mount components.  In some cases the "magic" components are only available in this form factor, in other cases the board must fit in in an engine, in a small cavity of an accessory, under a track section, whatever.  Soldering/assembling surface mount components excludes many guys just from the hassle factor (required eyesight, magnifiers, tiny tweezers, etc.).  From my perspective it would be a rare circuit where I could/would use larger through-hole components for the purpose of making it easier for someone else to assemble!  That is, I figure the "model" is someone designs a circuit and bare board for their own use...then shares the how-to for other OGR members.

Meandering from the topic but there two other sharing models I was thinking about, 1) 3-D print files to fabricate a missing/broken piece of an engine body or whatever, and 2) Arduino software sketches.  I bring these up to expand the perspective on community-sharing of ideas and how one could organize it.

But I have no solution. 

Anyway, thanks to GRJ for sharing his find!

Thanks Stan, glad to share the find, I was pretty happy to find it.

I agree with the SMT, for the most part that's all I use.  Can you imagine the size of the Super-Chuffer with thru-hole components?  It would have to be a G-scale product!   The only thru-hole I used was the regulator and the 8-pin DIP, and that was for a good reason.  I wanted to be able to upgrade the software in the field without someone having to unsolder the board and send it back to me!  This way I can just send a 70 cent part and have them plug it in.

The later Chuff-Generator is another case in point, it had to be as thin as possible, so I even went to the .031" PCB thickness as well as the SMT components to minimize the height.

The little DCS reset generator was an exception to the rule, it was simple enough and with the space available in the DCS-RC, I could use thru-hole components.  Now, for the funny part.  Of the 20 I'm making, 18 of them wanted the fully assembled and tested version, only two kits out of the 20!  This just goes to reinforce your point about the turn-key, and that was with common and easy to work with thru-hole parts!  I should have just stuck with the SMT version.

gunrunnerjohn posted:

You mean "train" or "MTH" or "Lionel" won't get you right to the post you are looking for?

Now that you mention it, I have had trouble using those search terms. The thread list returned was longer than the tracks on the NJ Hirailers layout! 

I think Stan has more good ideas with adding 3D print files and Arduino sketches. This could add more interest to the list. The points that both of you guys make (GRJ and Stan) about plug and play, turnkey and SMT components are good ones and I certainly agree. From reading a lot of posts here, I really do think that most folks want something that they could easily install with no soldering involved. I am guilty of being one of GRJ's 18 that wanted the DCS-WD PCB assembled and tested.  But, two kits were ordered so there is hope. 

I have never tried soldering any SMT components and for some reason I was thinking the DCS-WD kits were using SMT components? GRJ has clarified that above though, so I would have been ok with the kits. I totally missed that one. I guess I should have gone back and re-read the thread. I don't mind trying to learn to work with the SMT components, but my thinking was that I wanted these to work and it wasn't the project to start learning on. 

Also, as you both point out, I found that Digi-Key now has some components that are SMT only that had previously been available in a thru-hole version. I forget the part, but this happened to me a few months ago with something. I guess SMT is definitely the way things are headed. I need to get a few things to practice on around here.

I will make a test post in the next few days and we can see what happens. I will post it here first for you two to look at, before making a separate thread.

3D print files are hard to come by with all the components represented.  Other than generic stuff like the DCS-RC Watchdog timer I laid out recently with thru-hole components, I don't think I've had a design that had all the parts represented.  The 3D would be great, but creating the 3D models for missing parts is a major PITA!  I guess this bears repeating...

Nothing is so easy as the job you imagine someone else doing.

 I don't mind posting the 3D representation of stuff that is in the libraries, but unless I believe I need it, I'm sure not going to spend hours creating 3D models of parts that I have to add to the component libraries.

The DCS-WD kits started with an SMT version, then it was suggested to create a thru-hole version so anyone could assemble them easily.  I did that, and then got a couple of comments about making one fully assembled.  When I offered that, virtually everyone jumped at the chance to get the assembled version.  I suspect that's why Stan brought that up, it seems clear that the number of people that are comfortable soldering small parts to circuit boards are not a large percentage of the members here.

"Now, for the funny part.  Of the 20 I'm making, 18 of them wanted the fully assembled and tested version, only two kits out of the 20! "

I myself don't mind the soldering. I tackled one of the EMD kits and it went pretty well. I did have to wait for my LUX lamp to arrive though. I also have some new finer tips coming for my soldering station as the tip I'm using now was a bit cumbersome. Due to an injury to my left eye many years ago I'm a two dimensional viewer at this distance but it doesn't stop me. Besides, I love the smell of burnt fingers in the morning.  I elected to have GRJ assemble and test my DCS-WD's  as I consider his generous offer of $5ea a real bargain. Any time you can get an official pocket protector wearing certified electronic guru to assemble and test the circuit for it's a no brainer. 

Thanks to you guys for the R&D and all that you do to make this the greatest forum on the inter-web.

Milwrd

I must have made the assembly option too cheap.   Of course, these will be easier than the surface mount stuff, those are a bit more time consuming as it starts to involve tweezers and magnifiers.

I suspect I'll be lining a bunch of them up on the bench and smoking away.  I have a unique clamp system when I have a bunch of boards like this.  I use duct tape face out to hold the boards in place as I solder, works pretty well.  Given the simplicity of the operation, the testing isn't that much either.

Learning the 3D printing software is what has kept me from looking into 3D printers more seriously. From what little I have seen a lot of folks use the files on some of the 3D print websites where people post files for printing. Similar to the OSH PCM makers website. Not sure all are free to use though, may be a small fee involved and then you pay to have the item printed.

Some folks use Sketch Up which I fiddled with a little a couple of years ago. For me it would be a pretty big learning curve to become proficient with it I think. More than I wanted to learn anyway. They have a free version, but the full pay version is $$$ and I don't know if the free version would do enough to make train parts and things like that? Maybe it would, but there would probably be something you would need from the pay version sooner or later.

I must have gotten lost somewhere between the SMT version and the fully assembled one. But, the assembled price was pretty good.  I am sure you do have a good system for assembly though. Along those lines, I saw a pretty neat board assembly vise a few weeks ago. It had adjustable sliding jaws to hold the board and once clamped you could rotate the board from front to back. There was a little arm with a pad or something on it that you used to hold the parts in place. Of course that would probably be for thru hole stuff only. If I can remember what it was I will post a link.

Found it, it was a Weller ESF120ESD