I use terminal shields so that everything can be unscrewed. Additionally, with a 3D printer (which is under the $370 cost of all that loose wire), you can fab connector shrouds that provide better retention, provide pin 1 ID, labelling space, AND allow rapid cabling.
Power Distribution Board has screw terminal, bypass caps, and an LED power light. Mounted on Mega with Terminal Shield makes a CPU "sandwich" ready to mount and wire without soldering. There are only 11 soldered connections needed outside the PDB, most of those are attaching leads to buttons, the potentiometer, and speaker leads. All else, screws in and EVERY interconnect is severable.
I like those. Personally, I have held off on those, because I'd like a whole bunch of board-mounted as well as connecting cable like this, and 2, 3, 4, 5, and 6 pin wide. which once I put all that together would make for a rather hefty purchase...
Maybe next project I'll do that, just for fun. Question still remains: Because I do not know what the project will be, I will have to buy at least of each:
2,3,4,5 and 6 wire in-cable connectors
2,3,4,5, and 6 wire board mounted connectors (and corresponding cables)
The cables I see for sale are short. As you see in the box in the example project, quite a few of them are longer. So I should look for sets with longer wire?
make female headers for the modules, wires soldered to the headers, dot of colored paint for the power wire so it gets installed in the correct orientation. hot glue for both insulation and strain relief.
use the wire color code to keep things straight in your head:
Orange is 3, so I use orange for 3.3V VDC.
I save red ( 2 ) for 12 VDC,
use green for 5 VDC.
I always use yellow for the module RX on serial devices, and any random color for TX.
I2C: Violet and Gray for SCL and SDA. they are side by side in the color code, so they peel out of the wire ribbon as a pair.
if you need more than one wire of a given color, put a stub of colored heat shrink on both ends, to differentiate Serial RX yellow from SD card MISO Yellow / Red tracer.
if you drill and tap the mounting surface for 4-40 / 3 mm, up from the bottom, you can put a nylon nut on the screw and keep the soldered connections clear of the mounting surface .
plexiglass is an excellent mounting material, but any little flaw glares like a lighthouse. it can be cut with a table saw with an ATB blade
make a mounting template for your modules using Libre Office or Open Office drawing component. you can alter both vertical and horizontal in tiny increments with the percent adjustment to make a very precise template. put a + in the middle of the mounting holes. print it reversed and put it on a flat surface. put the plexiglass on that and you have the location for your mounting holes
if you are using an opaque mounting surface print it reversed and use an iron to transfer the toner from the paper to the mounting surface.
Power connection: I use what eBay vendors call a 4 pin aviation connector:
looking at the female connector, with the bump to insure proper orientation on the bottom;
ground
3.3V
5V
12V
clockwise.
every project can be powered from any location where I have an Arduino workbench without worrying about a magic smoke release.
I use brass metric standoffs for things that must be mounted high, like a TTGO T-Beam with the battery compartment on the bottom. attach the standoff with a screw through the mounting surface, male end up, and use a short standoff for a nut, so my kielbasa fingers don't have to hold or turn a Vienna sausage nut
Premade duponts come in 10/20/30cms. I buy M-F ones as they can be used as both screwed connects and as extensions. The shrouds gang the duponts without having to make your own connector blocks. Just strip off the number of wires from the ribbon cable, slide a pair of shrouds on et viola!, cables, ready to label & install.
I used to print/tape/drill by hand but the results were so-so. $300 later, I own a benchtop cnc for accurate drilling - every time.
Multiple, identical units, all CNC drilled for uniformity and consistently. 1/4" acrylic back plate can be hand tapped so no nuts are needed. Insulating spacers are 3D printed, as are the Mega and other component mounts.
Why? the tapped 1/4" acrylic holds 4-40 just fine. Adding inserts requires addition fab steps for little perceived benefit. The components are light, as are the mounts, extra strength is not needed.
The one spot where absolute strength is needed is the SD card holder, it's subject to repeated pushing. For that one item, thru hole mounts are used with nylok nuts on the inside
Again, design for manufacturability means the fewest parts, simplest fab, fastest fab.
Holds better than plastic thread doesn't matter if plastic thred is SUFFICIENT.
Hand threading doesn't crack or melt if the pilot holes are correctly sized. Power tap melts.
In industry we use Aluminum or steel, NOT acrylic for panels. Acrylic is used for prototyping and low volume for ease of machining.
What is "poorest" and / or "Mickey mouse"? Please do no resort to insults without explaining WHY. The point is to debate the merits, NOT insult the writer.
I strongly feel that the only way to make duponts is with commercial equipment that is unaffordable to any but med to large co's. You will get better, longer lasting cables if you buy preterminated wires instead of bodging it up with a hand tool. Not to mention the huge labor cost in one-at-a-time dupont fab. Get out your clock and measure the time to make, say 40, wires by hand, vs using premades.
Factor that cost in and how can you sell it and make a profit? Remember too that the retail cost is often 8x the production cost. Adding 5 minutes is 1/12 of an hr. At $24/hr labor that 5 minutes adds $2 direct cost, at retail that is a $16 price increase -- for 5 lousy minutes. If it takes 1/2 hour to install 11 inserts (enlarge hole, heat & press fit) then you're adding $100 to the retail price, and for what? More hold on something that doesn’t need it. That is what engineering for manufacturing is about.
The cost of the insert is nothing vs the cost of installing. And for what? At this scale, the plastic is sufficient. If I need more strength, we go to aluminum plates and thread THAT.
I didn’t say you were mickey mouse, the practise of cutting 4-40 threads in 1/4” plastic is mickey mouse construction.
Highly suggest you pick up some of these inserts and experiment with them; you will convert to the method.
30+ years ago, I was where you are now when I started to use these brass inserts.
I have worked in several factory situations (many years back) where these inserts were/are used in quality production; threading plastic for fine threaded bolt insertion, is never done in industry and is not what is recommended for hobbyists.
4 cents per hole is not a hardship.
Suggest threading plastic for 4-40 bolts takes longer much longer than hot inserting brass inserts (about 5 seconds per hole)11 * 5 = 1 minute .
