Shrinking the prototype

So I'm at the point where I want to convert my prototype, into a packaged, functional unit. I'm really new to electronics and electrical, and I'm afraid that I don't quite know how to ask the question, in a way that gets me a lot of useful results. I've spent a lot of time googling and searching the forum, and only come up with marginally useful results.

So my question is: are there any good resources for describing how to package a design? And by that, I mean specifically how to distribute power, provide connections for external power, etc, etc, etc.

I will be 3D printing my enclosure. I'm going to dedicate an Arduino R3 board, and I have a 4 relay module that will go inside. The relays are for switching 120VAC, and my mind tells me that I want some sort of power bus to make the high voltage connections - but I can't say for sure that's right.

I'm also thinking that I might like to have a PCB made, that backpacks onto the arduino, to further simplify, and condense the packaging. Are there any decent free programs that any of you use for this?

I'd love to have any other advice on the subject.

Thanks in advance

That board is big! The first step I'd take towards shrinking would be to use a smaller board, like a Nano or a Pro Mini, or go for a standalone MCU.

Yes, there are, but they will help you with the layout only. The design you will have to do yourself. It's like with IDEs: they will help you with coding workflow, but you still have to provide the code.

That's OK. Just as long as I don't have to manually lay out paths and check dimensions of everything. (some basic checks and validations in the program would be good) More about throughput, than doing the actual work for me. My level of circuit sophistication is low enough, that as long as the program follows (and constrains me to) some basic templated rules for PCB design, it'll be great.

If this is something you want to sell, consider hiring professionals: an EE to design a reliable, robust circuit and PCB, and a product designer to lay out the package.

It's not something that I want to sell. It's something that I want to use.

I AM the professional for the product design. What I am NOT, is savvy with electrical/electronics design. But it's OK if it's not optimized for consumer use. I just don't want exposed dupont cables and modules cheesed onto plywood.

Go download KiCAD 5.

Also I agree with @330R. Don't use an Uno, they are really big compared to what you can get from the Nano lineup or even a Pro Mini if you are willing to sacrifice the USB port.

Thanks for the recommend on the PCB layout app.

Big NO on losing the USB. As stated, this is for my personal use, so I have no constraints on size. Also, I'm keeping the scalability. So sticking with the UNO.

I baselined the whole thing on a Mega, so it's already coming down in size. As a newbie to this, I want to keep this particular layout as easy to upgrade, as possible. Arduino and clones are so cheap, I really see no reason to shrink this to highest degree. It just has to be tidied up.

If you don't need it to be small, go for it.

I'm trying to package everything in an octagon shape. The flat on top to have (2) plug ins for lighting, the flat on the bottom has power cord coming in, with another plug adjacent, for a cord running to a floor level appliance. Left side (as facing) flat to have the USB port. I'm still not 100% sure if I'm going to be able to use an onboard power supply (chained off of the 120VAC incoming), or if I need to dedicated an external power supply to the board.

Then, the LCD is staring at me, like reading a stop sign.

In case it wasn't obvious, this whole package is wall mounted.

Sounds really cool. Good luck!

Unos in final products have another problem besides the size. There are exceptions (I own a few of them), but generally they don't have solder holes or pads, so you're stuck with jumper wires which make for unreliable connections when left unattended. Or you can always desolder the female headers, but why do more work than necessary and alter a benchtop prototyping board that was doing its job?

The loss of USB is no big issue. You can use a little USB to TTL board or another arduino as a programmer. Do you plan very frequent updates of the product?

The problem is, I don't currently own any soldering equipment. I typically use wire wrapping for more "permanent" type small circuit projects.

Then get one :astonished: .

The round pins are NOT designed for wire wrapping and will produce intermittent permanent connections.

I use breakable pin headers. They are square. And they work well.


Honey, I shrunk the prototype!

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