This project hasn't been posted to the public yet but if you're seeing this,
you're one of the folks from VFU who are helping out with alpha testing... thanks!

This is the draft version of a case for a Raspberry Pi made in the style of
a Vectrex.  Although it is not specifically intended for use with a Vectrex
emulator as a mini Vectrex, it could certainly be used as such.

When I say 'draft' I really mean it - the case is not really ready for use,
unless you're someone willing to put some effort in to either making mods
to the OpenSCAD code, or finding specific usb cables that fit in a tight space,
or are willing to power your Pi by soldering to a couple of terminals underneath
the USB power socket...  it's very much an initial draft, and the only reason
I'm mentioning it to a few friends on the Facebook Vectrex group is so you can
point out any design flaws I may have missed and which need to be worked on before
a public release.

Currently there are two issues worth mentioning: 1) getting a USB power cable
to the Vectrex is tricky - although there is lots of room in the 'backpack'
section of the case for batteries or a voltage converter, routing power from
that 5V source to the Pi motherboard is tricky.  And 2) At least with the Pi 3
I'm using and the screen I have, it gets pretty warm - warmer than I'm comfortable
with for something I would expect others to use.  I can certainly add holes in
the case (even in the same locations as on a Vectrex) to improve air flow, but
the heat is in the area between the Pi and the LCD and even with a fan running
in that area already, it's not cooling very well.

And on the software side, although I have it booting up correctly in vertical
320x480 mode (i.e. 3:4 aspect ratio), by the time it switches to user mode -
whether that's the console prompt or the GUI desktop - it draws the screen
in a 320x213 subset of the display (in the center) in 4:3 aspect ratio.  I.e.
everything looks correct in terms of orientation but is tiny and doesn't fill
the screen.

So bear those points in mind if you decide to print this.  It probably won't be
something you'll use in this form.  You'll just be printing it to test the fit &
finish and to point out things that need to be done.

One thing that I desperately need help with is a printing problem: although in
the 9 months I've had a Bambu printer, everything has printed without problems,
with this model I've started getting some edges that curl up.  I don't know
whether this is just an age/maintenance issue or if it's because the components
on this plate are large and fully cover the plate - the curling has all been
on the extreme left edge of my printer plate.

Anyway, caveats aside, lets move on to the actual design:

The case has a lot of space inside so that it can be used as a project enclosure
for multiple applications.  It was constructed in separate parts that fit together,
because:

  1) this allows us to print the enclosure without needing support material
     for the many overhangs that are needed in an enclosure like this. (The
     downside of this is that it needs some assembly, which can be a bit of
     an IQ test!)

  2) the enclosure can be more easily customised by swapping out only
     the modules that you need to change: the screen is one module, the
     SBC is another, and the power supply is a third.
     
  3) if you are customising the enclosure for your own projects, you will
     only need to modify and print a single piece at a time, which should
     speed up your development iterations - reprinting a single component
     should take maybe 40 minutes, rather than the 3 or 4 hours it would
     take to reprint the entire case if it were made in only one or two parts.

You will almost certainly need some custom cables to power your Pi, whether
it's a slim right-angled connector for the USB power input, or jumpers to
the GPIO pins if you want to power it that way.  You could certainly add
an opening in the side of the case to allow direct connection of a USB
power supply, but I wouldn't do that myself as it would detract from the
asthetics of the enclosure.  The optimum way of adding power if you are not
using the USB input connector is to connect to the 5V and Gnd pads on the
underside of the PCB because these points are effectively the same as the
USB input which has voltage regulation and a fuse.  Connecting directly
to the GPIO pins is not as reliable.

I'll eventually design a specific backpack for battery-powering the Pi,
and invite users to supply their variations for different sizes of
battery etc.  Some battery options will require circuitry, such as using
two LiPo's in series which would mean a voltage between say 8.2V when
fully charged and 7.4V in average use.

The screen holder is currently configured for a 3.5in display that
attaches to the Pi directly.  I believe there are several available
in this style.  The most recent one I've bought was this one via
Amazon for $16: https://www.amazon.com/dp/B0D4DL38MF (which includes
a fan).  It is identical physically to a much older display that I
own so I suspect most of these 3.5in displays will be extremely
similar.

Although working from the specs I thought the screen would be perfectly
framed by the bezel, the displayed image turns out to have a 1mm black
gap at the side and a 2mm black gap at the bottom.  The next revision
should move the screen a tiny amount to center it and the bezel will
be marginally increased in order to remove all of the black border.

Any full-sized Pi should do as there are currently no version-specific
case mods in this print that would cause problems with the slightly
different sockets of the various pi models.  A Pi zero would work as
well but all the Pi's will need the case to be modified slightly to
hold them in place - I haven't done that yet though short-term you
should be able to improvise something with a piece of folded cardboard
inside the enclosure (until I've added some sort of holder to the
design).  Potentially a Pi 5 may get too hot.  I have one on order
and will try it as soon as it arrives.

There *is* however a small shim piece which sits between a Pi 3 and
the LCD - this was to keep the display level if you weren't already
using spacers between the two boards.  It's optional and it probably
won't fit other versions of the Pi, but my intention is to design
similar spacers for all the other Pi models (most of which I have
an example of though it may take me a little effort to find one of
each type!)

The area in the front at the bottom, which on a Vectrex would hold the
controller, has not yet been fully designed and is currently a place-holder.
If you plan to use this with a Vectrex emulator, you'll probably want
to do something in that area to handle whatever sort of controller
you plan to use with it.

There is no outlet yet for a cable at the back (mainly because my
initial iteration was intended for use with a battery pack.)

The external appearance of the enclosure is only an approximation
to the style of the Vectrex for now.  I'll refine it to look more
Vectrex-like over time, but I'm currently concentrating more on
function than form, such as working out a good way to get power
to the Pi without cables coming out the side in places that have
no cables on a real Vectrex.

So in summary, this release is usable by folks willing to put a
little work into it, but I would suggest that it's probably not
appropriate for anyone who is looking for something they can just
print and use immediately - if you decide to print this, it's
primarily as a favour to help me improve the design at an early
enough stage that changes won't be too disruptive (and I thank you
very much for doing that)..

I will be uploading both .3mf and .stl files, and the OpenSCAD
.scad file which you can use to make modifications to feed back
in to the project.  Look for the highest version number in this
directory and mention the version number when making reports
to gtoal@gtoal.com (short comments are probably OK on the VFU
group but long comments might be better by email).

The OpenSCAD code is not as neat or as parameterised as I would
like it to eventually be.  This is definitely a work-in-progress
project.


Graham
3 Oct 2025