GRJ.....Five bare boards and a BOM plus the written notes you mentioned earlier would be fine to start. Gerber file would be a plus.
Richard
John,
If you were to get enough preorders for a factory build run of 100, what would the unit price be?
@Ron_S posted:John,
If you sold the PCB and published the BOM, for me that would work. Between Digikey and other suppliers, the components would be grouped individually, which would allow me to sort and install in order so I didn't get lost."
This would probably work for me as well John. I have a Hakko station with a fine tip head and .020 solder. Plus a magnifier light fixture, can't recall its power though. Would I need anything other than this do you think? It's the steadiness of the hands that is likely to be the big issue I think, lol. 
Rod
I'm in for a few bare boards when available.
I'm in for a half dozen kits.
@prrhorseshoecurve posted:For me it would be like your lighting and YLB kits of just "plug and play". Catering to the 10's that may have a soldering station and soldering skills is foolish.
Maybe so, but to get these assembled it would require me investing several thousand dollars minimum with no guarantee of recouping my investment. I can't really afford to take that gamble. It's simply not cost effective to get something like this built unless you commit to at least 100 units or more. I'd much rather go the fully assembled route if it were possible. I just don't see the demand for something specialized like this MB as for stuff like lighting and battery replacements.
@Ron_S posted:If you were to get enough preorders for a factory build run of 100, what would the unit price be?
I'd guess in the $40-45 ballpark, I haven't checked on assembly of this particular design. I just go on what other projects with a similar parts count have cost. It might be more if I get snagged again with the Trump tariffs, last couple of builds I paid 25% more than expected!
I’ll commit to 5 boards no matter how you end up doing it.
John,
I want 5 boards for sure with a bom and diagram so I make sure have the components properly placed. Like Rod my only doubt is my hands shaking but this looks intriguing to build. Maybe one every few weeks.
If enough interest is there I would be in for 1-2 boards assembled.
I would vastly prefer to do an assembled version, but I'd need to get commitments for at least half of the run in order to shoot the dice and order 100 boards. I know I'll be using some as time goes by, I can see using this and the ERR Cruise Commander M for some really nice feature laden diesel upgrades. Rule-17 lighting, cab light control, functional ditch lights, etc.
I envision it working well in the Williams and proto 1 diesels I make TMCC, making the entire upgrade much better.
I envision using them in several older Weaver SD-40's and pre-TMCC Lionel diesels, just as Ron plans. So I would commit to minimum of 6 assembled boards, and likely 5 more after I get the first batch installed. These should also work well with your sound board, right John? I would need to get you to Fedex them, if possible, just to avoid the whole cross-border mail thing.
I would also take perhaps 5 bare boards for minimalist installations, without all the functionality.
Rod
I think what we need is to start a list of folks that will commit to a specific quantity of the full up boards and see if we reach critical mass. I think I might take a deposit on those like I did with the TMCC buffers to cover some of the costs. If we get enough commitments, I'll go for an overseas build.
I will take 2 built boards for now John if in the $40-$45 range.
John how much for the empty boards ? j
In looking at the overall picture, I don't see this making it to enough firm orders to do an assembly run. That being the case, I'm going to simply offer the blank boards I have for $3/ea.
I have posted all the current build data in the first post of this thread. The schematic, BOM, and assembly drawing all reflect the current board. The Gerber files are also there if you want to make your own boards.
Hi John, I have been out of the loop on this project, and just curious where it stands. I assume a production run is still unrealistic? Have you recieved your order for the final boards, and are they working as expected?
I wish there was some easy way for you to mail me a few bare boards, but cross border mailing is a mess still. That being the case I may have to just order a few boards from Osh Park. How do you feel about sending me a few of your boards via Fedex or UPS?
Rod
Yep, I assembled one of my "final" boards, and all went well. It all functions as designed. I only got a couple people that actually bought the blanks, so I'm glad I didn't shoot the dice and actually get them built, I'd have a lifetime supply and a big hole in my bank account. Any future projects like this that I think about getting assembled will be on a BTO basis, I think talk is cheap when it comes to things like this, but then reality bites.
As for shipping them to Canada, I suspect you could take the Gerber files and send them to JLCPCB and get these made cheaper than I can send them. I suspect that Chinese shipping to Canada is a lot cheaper than US shipping to Canada.
John, do you have any more blank boards? If so, I would like to get a few.
I'll need one someday. I have the perfect project for it but it wont be anytime soon.
I still have about 20 blank boards.
Here is the "final" fully assembled product. Other than a couple of crooked components, it's as intended. I noticed when looking at the picture that the 680uf cap was not straight.
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Very nice John, looks good to my eye! 
I would sure take about 6 of your blank boards, except for the shipping business.
I will check out jlcpcb and allpcb and see what those options look like. Thanks for the update!
Rod
John, how do I contact you to get some bare boards? Two boards would suffice for me.
John, are your trace widths based on 2 oz or 4 oz copper thickness?
Rod
@penn station posted:John, how do I contact you to get some bare boards? Two boards would suffice for me.
Same as always, my profile email.
@Rod Stewart posted:John, are your trace widths based on 2 oz or 4 oz copper thickness?
They're standard 1oz copper. I use a trace width calculator to verify the current carrying capacity. The heaviest current is the input power, that's at most a couple of amps if you have a smoke unit running off the R2LC. The 2oz copper tripled the cost of the boards, I didn't see the need. The power carrying traces are shorter than 2" and are .508mm in width.
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Thanks for that clarification John!
Rod
So, Did you ever determine the price point per board per quantity. If in fact you had these built...Maybe we can get you over the border..
In quantities of 100 or less, the total costs for parts & assembly are around $30-35. Recent shipments have also encountered a 25% tariff, adding to the pain. It will also take more work to get them ready for assembly, documentation like assembly drawings, detailed BOM lists, etc. have to be created. Given the response, I just don't see that happening, and I can't really afford to be stuck with several thousand dollars worth of fancy motherboards.
I posted all the files necessary to recreate the boards in the first post of this thread. I got a batch of blank boards, and I'm keeping some for my use and selling the rest of them. It was an interesting exercise, and I'll be able to use the ones I've built in upcoming projects.
GRJ... On the smart mother board.....D2 next to the track power plug, which direction does the cathode band go? Other locations have a dot which I would think means cathode. Your pictorial on page two seems to show cathode band to the left. Is that correct?
Richard
I think there is a market for $35 completed product. I would buy several . I don't think that this forum is an accurate market survey as I just ran into this post. I think that the initial discussion probably lost many including myself.
@Rppoind posted:GRJ... On the smart mother board.....D2 next to the track power plug, which direction does the cathode band go? Other locations have a dot which I would think means cathode. Your pictorial on page two seems to show cathode band to the left. Is that correct?
Richard
The cathode (this is the LED), has a little T on the back, that points toward the power plug. That dot on the silkscreen was inadvertently missed.
@Art Lites posted:I think there is a market for $35 completed product. I would buy several . I don't think that this forum is an accurate market survey as I just ran into this post. I think that the initial discussion probably lost many including myself.
At $35 I might break even, so that's pretty much a non-starter for me. The problem here is when the Chinese make some little board like this, they make 50,000 or more of them, and that brings the cost per unit way down. Making 100 or so is a whole different ballgame. Stuff I buy for a buck or two from China I couldn't make for $10.
Many thanks GRJ,,,little T pointing to track power plug it is for D2. Last thing I want to do is solder the LED on backwards.
Richard
GRJ.......Finally got my 1st motherboard assembled and inspected. I plan to start with no R2LC and connections. If red LED lights and no smoke I'll add a R2LC and a coupler and move on from there. Question on LEDS. I see several resistors on your led bench test perf board. Does your motherboard need the same 470 ohm resistor as standard TMCC? Does it need a diode for conventional? Thanks for all your work on this project.
Richard
Yep, the requirements are the same as any other TMCC device using the R2LC, the lighting outputs come directly from the R2LC. You don't need the .01uf load caps for LED lighting as I put those in the board design for the lighting and smoke outputs.
Still have a handful of the blank boards if anyone is interested...
GRJ....I remember you wrote that the Smart Mother Board would drive a ERR sound Commander from the
"sound" EH connector. Will that connector also drive a Lionel TMCC sound Mother Board? I am trying a 691-MB00-15C loaded with a RS 4 power supply and Sound card. It is a two port sound only board. Lights and couplers are working. R2LC feature set to 4. All i'm getting is engine idle. Several times on power up I get a coupler air release when I press uncouple. Next coupler command it opens but no air release. I have the serial line on pins four on the SMB and the sound board per my pinout for this board. Any idea what I'm missing?
Richard
It's a bog stock serial data output, so it should drive any TMCC sound board. The 4-pin sound connection on the smart MB is identical in pinout as the ERR boards, so the cable that comes with the sound boards should drop in and play. It does for me. I honestly don't know what you're missing, it should be dirt simple.
Thanks John...I'll take a day off from this and do some yard work. Wednesday get all the doc's out and look at everything.
I'll hook a DCDR and ACDR and confirm that is working. To be honest I was ready for the first SMB to be inop. That puts me ahead of the game.
Richard
Hi John; I have finally ordered a few of these boards from OSH Park, and I'm just getting set to order up the parts that I don't have in stock. Just curious; do you have any kind of ready available list of digikey PN's from the parts BOM that you ordered for your builds? That would certainly make ordering easier, especially for a lazy type such as myself.
Thanks, Rod
