Stingraze -
Welcome to the club! Of 3D printer owners and people 3D printing their own HPCs. Something that may be of interest to you - I've just bought a cheap 3D pen
(the kind they sell for kids
) and I'm going to be experimenting with sticking printed parts together with this.
Mike -
My main focus has been on getting the thickness down on my various 'HPC' designs, here are a few things I've done to reduce thickness and generally make use of the limited space available:
- I accommodate a full-sized Raspberry Pi by having a raised section of the base to cover the sockets and a matching cutout in the lid to clear this. I'm not sure how well this would work with your configuration
(Pi in the lid
), but you might be able to do this in reverse? I've tried to show this in the photo - I may have some better pictures for this.
- I reduce the vertical clearance I need above the Pi by using a little PCB with a pass-through connector on the GPIOs - See here:
https://shop.4tronix.co.uk/products/gpio-interceptor This lets me use GPIOs without adding any height.
- I've found an LCD that's especially thin and uses a mini-HDMI connector - Took quite a lot of hunting on Aliexpress and similar sites. This one's 7 inches but I've seen some similar displays in smaller sizes. Also made my own HDMI cable but this was mainly because it had to go through the hinge.
- I've made quite a few of my own cables to get specific lengths - For USB there are quite a few solderable connectors available. I've also used ribbon cables wherever I don't need to carry high currents - These are obvously thin but can also be folded to help them stay in place.
- You may be able to save a little space with your power bank by removing the casing - It's almost certainly just a battery
(possibly multiple batteries
) and a tiny PCB inside.
- For the keyboard I'm not so sure - It's very difficult to find keyboards smaller than the size you have that still have proper scissor switches - If you can tolerate little clicky 'metal dome' type keyboards there are smaller options. I've also seen replacement keyboards for GPD pocket / One Mix Netbook and similar machines popping up on Aliexpress* - These are a little smaller than the keyboards you and I are using, with scissor switches, but are quite expensive. You'd also need to use an Arduino or similar to read the keyboard matrix and make it appear to the Pi as a keyboard.
- I've designed a hinge that combines the friction mechanism and cable path into a 3-part assembly - I'm more than happy to share this with you but I have some concerns over how long it will maintain an acceptable amount of friction - I'm trying to work on the design so the friction material is more easily replaceable.
Sorry to bombard you with information here - It's just that I've spent quite a lot of time on it and I'd be happy if my work can save you or anyone else a little time on your own designs.
* I'm not trying to advertise Aliexpress here
(despite how it may seem
) - There are just some items that only seem to be available there.
(Case Base and Lid - Features Highlighted.jpg)
(HPC Mk5 internal features.jpg)Attachments
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Case Base and Lid - Features Highlighted.jpg (40KB - 0 downloads) HPC Mk5 internal features.jpg (60KB - 0 downloads)
The 3D printer I bought prints only up to 12cm x 12cm x 12cm, but I hope to make a good use out of it and learn 3D CAD as well. 
Do you have any good ideas? 
