ArduBigBOY (WAS: My Homemade: Pro Micro, SSD1309, with Flash Cart)


(serisman) #61

Thanks! Yeah, if felt wrong sending out a PCB with so much free space. My usual designs are much more compact and cramped because I am always trying to optimize for as little area as possible (to reduce costs… using OSH Park). This time, I actually needed to have the larger footprint (and went with PCBWay where any size under 100x100 is the same cost).

Yeah, that’s my usual approach, but this time I wanted them so badly that the wait seemed painfully long. I am planning on publishing the pcb (and schematic), hopefully this Friday.

Yeah, still waiting on the 5032 2-pin SMD crystals. Supposedly they have been in the country for two weeks already… why haven’t they been delivered yet? :frowning:


(serisman) #62

Here is a sneak peek of the 3D printed case I have been working on for this (compared to an actual Arduboy):



There are still a few small tweaks I want to make before calling this good enough for version 1.

I am also looking into other options for the buttons because what I have used so far are very ‘clicky’ and I would love to get closer to the feel of the official Arduboy (gotta loves those buttons!).

I did finally get the correct 16 MHz SMD crystals, so the bodge job is gone.

I hope to button up and release everything later this week, in case anyone wanted to build their own.

I do still have a few of the initial small batch run of these available for sale. PM me if interested.


#63

Looking very nice! I like the RGB LED shining through the case. Those vast white surfaces look like they may want some arcade artwork on them.


(Kevin) #64

If you want the correct button feel you are looking for something under 100 nm activation force, or as close as you can get. In smd packages that are easy to source typically 150 is about as low as you will find. Which is OKAY, but still puts you on the threshold of feeling “I wish this was just a little softer to press”. Standard run of the mill button force is going to be at 250.

Arduboy specifies 85nm but I’ve told the factory that anything under 100nm is fine. I’ve tested all the way down to 60 which starts to get too soft. If you somehow have the ability to add a silicon or rubber layer over the button this will improve the button feel as well, I considered doing this in production but figured it wasn’t necessary, and the process might have been complicated or expensive.


(serisman) #65

Would love to know if you ever sourced those metal ‘domes’ that you are using on the Arduboy outside of going to a ‘factory’. I can’t seem to find them on the usual channels. I probably just don’t know what to search for. With those domes, I can probably fabricate the rest the required button and I already have PCB traces for a soft touch type button.

I did find some decent looking SMD soft touch / silent silicone buttons, but they are much taller (5mm) than would be ideal for this case design (and I have to wait for weeks for slow China shipping).

In the meanwhile, I will look around and see if I can hack apart any keyboards, remote controls, or the like to re-use any of their silicone domes.


(Kevin) #66

You can’t really find them to purchase straight away. The only time I was able to get something like this was to request a sample set from a manufacturer online and they sent me several thousand and almost as many marketing emails.

Check out stuff like this, adafruit is expensive but it’s the right part:

The manufacturer ALPS has some really excellent stuff.


(serisman) #67

Yeah, I bought some of those, but they are too big for this case (and the pcb would need to be re-worked).

I actually found that I can disassemble the 6x6x2.5 smd buttons that I am currently using (pretty easy to do), and there is a metal dome in there that looks about right. Testing it now.


(Kevin) #68

Yeah all these type of buttons actually have snap domes in them somewhere. The problem is the “land” or the area they are intended to come into contact with. Unless they are designed for a PCB land then it’s gonna be very difficult to re purpose them.

That said, these button matrixes only cost fractions of a penny. You might need to buy several hundred or maybe a thousand but you might not actually be out that much money. I mean, if you’re really committed to the snap dome route. There are lots of options if you go with microswitches too.


(serisman) #69

snap dome - That’s the name I was looking for! I see lots of them now. Thanks!

Yeah, looking into that now. I did set up a set of alternating pcb traces that works great with the silicone rubber button domes, but is a bit fiddly with these metal snap domes. I think part of the problem is the pcb tinning is slightly lower than the solder mask. If I raise it slightly it seems to work pretty good, but if I get to much solder on the traces it stops working again. A properly designed pcb trace would make these much easier to use (i’ll address that if I do a v2 board).

Yeah, I have micro switches now, but they are too noisy. Hence the need to look for something quieter.


#70

Snaptron has a range of snap metal domes and offer a free sample box with many different domes to test out. I got one ages ago to test for a potential product and still have it somewhere.
https://www.snaptron.com/free-samples


(serisman) #71

Thanks! I submitted a sample request. We’ll see if they honor it.


#72

I cant remember if I used my school email or my gmail but they were pretty chill when I explained the product I was trying to make and sell.


(Simon Merrett) #73

Try lcsc.com for the snap domes. Not sure if you can get the soft touch version but they are more reliable for production than aliexpress.

When you say protected battery, do you mean integrated with the battery or a circuit you have put on your pcb?


(serisman) #74

There is a protection circuit integrated with the battery. I went back and forth on whether the protection should be on the battery or the pcb, but the batteries i found already had it integrated, so i skipped adding it to the pcb.


(Simon Merrett) #75

That is what I’m starting with but most of the batteries don’t seem to spec their circuit so I’m inclined to implement my own protection circuit on a future version of my WIP design.


(serisman) #76

I modified the case design a bit more: the DPAD now has individual buttons, the buttons now have tighter tolerances, and there is now an end-cap to cover the expansion header when not in use. While not perfect, the buttons do feel and behave better now.

I am finally calling this first version done!



I also started putting together some additional documentation on a new Thingiverse project page: https://www.thingiverse.com/thing:3250270

I will probably start a new ‘official’ thread for this project and keep this thread more about my original homebuilt.


#77

Looks very neat. I like the notches at the side and top. Gives it a nice unique look.


(serisman) #78

Thanks! This was a lot of work, but I am pretty happy with the way it turned out.

The notches are for the power and mute switches. They were the easiest way I could think of to allow access to them without introducing more parts and complexity, and they kind of work similarly to the power switch on the real Arduboy.


#79

Great job, looks very slick!


(serisman) #80

I’ve been playing around with some other filament colors and post-processing:

These are with some light sanding of the body (I should have done more) and then painted with a metallic silver spray paint. I think I like the black buttons better than the gold ones, but interesting effect nonetheless.

The painted body does block the LEDs from shining through the cover, so I will probably need to drlll a hole for a light tunnel or something.