Power/DCC Bus Taps - Does Anybody Make One Like This?

[John]

Is this your type of wiring John? 

(Attachment Link)

BTW, this is for real - it is under an NTRAK module of one of our club members. 

Looks good to me ..

[djconway]

Does it work? If yes don't pick on it.

[C855B]

Does it work? If yes don't pick on it.

Disagree. This kind of rat's nest in an N-Trak module is not OK for something that needs to play well with others. It might work today, but after being bounced around in transit and setup/teardown it may (i.e., probably not) work tomorrow, likely defy any and all attempts to debug, and then be set aside for the roundtuit which will never arrive.

[peteski]

Disagree. This kind of rat's nest in an N-Trak module is not OK for something that needs to play well with others. It might work today, but after being bounced around in transit and setup/teardown it may (i.e., probably not) work tomorrow, likely defy any and all attempts to debug, and then be set aside for the roundtuit which will never arrive.

Thankfully most of that "nest" is not related to track wiring, but we almost had a fire due to an overheated resistor in one of the circuits!  I agree that neat wiring is important on items which are used as a part of a larger communal layout (like NTRAK).

Cleaner installations (like what I did on the under the carnival scene) is much easier to work on and troubleshoot.  The wires are glued directly to the acrylic base. 
The twisted pair is just temporarily tacked on (to supply power). Normally the USB connector will be used (to supply a non-USB power to the rides and lights on the module).  I used a standard USB connector because they are quite rugged.

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[C855B]

Very nice. You're hired.

That overheated resistor episode is a hint at the inherent risks of sloppy wiring or similar inattention. I had an engineer acquaintance who was, frankly, a genius with many great ideas, but he tended to be short-sighted when it came to rushing his ideas into hardware. He cobbled-up a system once and "didn't bother" to fuse all the power supply leads of the distribution panel, the main fuse was sufficient... NOT! He burned-up his car when a prototype board shorted-out.

[peteski]

Very nice. You're hired.

That overheated resistor episode is a hint at the inherent risks of sloppy wiring or similar inattention. I had an engineer acquaintance who was, frankly, a genius with many great ideas, but he tended to be short-sighted when it came to rushing his ideas into hardware. He cobbled-up a system once and "didn't bother" to fuse all the power supply leads of the distribution panel, the main fuse was sufficient... NOT! He burned-up his car when a prototype board shorted-out.

. . .  and even that probably didn't teach him a lesson and he kept on being sloppy with wiring, right?

[C855B]

Well, yes and no. He paid more attention to fusing after that.

Seriously... he was more or less in the biz of promoting an early geolocation and vehicle tracking system, back in the early '90s when GPS was a black art. He freely admitted the mistake, and incorporated the hard lesson into his talks.

[Philip H]

I'm sure it will become apparent when you post on layout pics, but I am still not sure how this:



Replaces the original board diagram you showed.

Perhaps if I apply more coffee . . . . 

[C855B]

Just a different way of getting to the same result. I have more bits coming (detector boards, specifically) before having something to show, so it will be a few days before pics.

[lyled1117]

Kind of a late response to this  , but to the idea of making this a cheap PCB, what about a single sided one? Using some of the cheaper PCB materials like CEM-1 or CEM-4? I don't know if the PCB manufacturers suggested here offer these, but using double sided fiberglass is overkill for the desired product. I took the original GIF and slapped it around a bit to show one way it could be done with beefed up trace size just in case higher currents are anticipated. This method should reduce the PCB cost noticeably, but that might not be as true in low volume

Lyle Dowell

[peteski]

Nice alternative, but as I understand most low- or medium-volume PC manufacturers are set up to produce double-sided standard-thickness fiberglass boards. That is the cheapest. Anything else costs more (even cheap single-sided phenolic boards). Of course same doesn't hold true when larger runs are involved (by larger I mean thousands).

[lyled1117]

Doesn't surprise me that 'cheaper' methods might not be available. I'm use to PCB houses from my layout days.   A single sided PCB does put the manufacture of a small number of PCBs in the realm of a home hobbyist. A friend of mine uses film he prints himself on a printer to screen PCBs for etching with decent results. Smelly ferric chloride is needed of course. He has done double sided too, just takes careful alignment of the two images. Then soldering both sides of the resulting PCB where a plated hole would be on a true double sided PCB is needed.

Lyle

[peteski]

Doesn't surprise me that 'cheaper' methods might not be available. I'm use to PCB houses from my layout days.   A single sided PCB does put the manufacture of a small number of PCBs in the realm of a home hobbyist. A friend of mine uses film he prints himself on a printer to screen PCBs for etching with decent results. Smelly ferric chloride is needed of course. He has done double sided too, just takes careful alignment of the two images. Then soldering both sides of the resulting PCB where a plated hole would be on a true double sided PCB is needed.

Lyle

I also produce my own PCB's. I don't think FeCl is smelly at all.  There are also other etching chemicals available. But in the last few years the costs of having an outside company produce your boards has dropped dramatically. They usually offer free design software and quick turnaround time. There are dozens of companies to choose from. So for anything that needs to be made in quantities more than just few boards it make sense not to do them at home.

[C855B]

Putting an exclamation point on this thread, thanks to an ad in Model Railroad Hobbyist, I was reminded of the original inspiration for this idea:

http://acculites.com/index.php?main_page=product_info&products_id=658

I was designing the same thing, 'cept with more taps on the board. Can't fault the price in quantity. I'm going to stick with the Wago taps, however; they are tool-less, work well and very easy to use.