Yeah it’s pretty tricky when we both want to pull heat out of the phone and not feel the case heating up - conflicting goals.
The idea of trying to get a tiny fan in there to push air through is still an interesting one, but definitely a v2 type of project, maybe I will try that some day when I get crazier.
If you do… A standard mini fan or two would be easy to fit - just make the back that thickness, glue them in their holes and add a couple of holes for replacement air to get into the airgap + make recesses for cables, battery and switch (could fit coin batteries into that 5mm back). Would be more sane than what is sold for “gaming phones” (do a search for phone cooling fans - it’s pretty wild). Mini fans also come with usb-c connectors, if you want to use phone battery.
Like (5mm thick, 15mmx15mm widths):
These would be cool too (very mini at 4mm): BSB01703HA3-01 17mm blower fan 17x17x4mm DC3V 0.20A cooling fan for mini devices | eBay or 15x15x4 mm Super kleiner bürstenloser DC-Lüfter Ultra Tiny Mini Micro Kleinster | eBay or SUNON 1703 17x17x3mm1.7cm UF5H5-503 DC 5V 3 Lines Micro Mini Axial Cooling Fan | eBay)
Other things… You seem to have .05mm spacers for that gap I think I may need to be bigger gap but that’s not the point for this: you could try making those static form spacers into more flexing bumber shape - and/or maybe use such on the sides too. The idea being that when kinetic energy is transferred to the case (you drop it and it hits the floor) and it transfers that energy to the phone (but dampens it via the case), the static shapes transfer as well as their form and material allows. But if those same shapes would be something that itself bends, then the transfer of that kinetic energy could be much less. For this flexing movement a bit more room may be needed, depending on the shape but thick back and sides would allow to create such recesses.
One such shape would be something similar to a diving board: a longer piece that’s only attached from one end, is a bit of an angle (or is arch like) towards the phone and can bend a bit down. If those are on all sides, it would keep the phone snugly in place while allowing for airflow and possibly keeping the phone a bit more safe. If it’s designed right, those should be printable.
A bit more “version 2” maybe.
Like (not to scale and measurements are just suggestions - designs need testing):
I think that would be printable yeah. But possibly better with slightly more flexible PETG (I’m using PLA, that might still work though). I’ll keep that in mind if I start doing further variations, that’s a cool idea.
Edit: Oh, most of the spacers are .5mm, not .05mm. But yeah I guess it’d still need a little more room for “inertial dampeners”.
After the inertial dampeners are invented, we just need the warp drive and shields, maybe a photon torpedo bay at the top for firing at Apple users?
It is more productive to continue developing the Purism community instead since our collective pool of replenishable resources does not compare favourably against the duopoly.
“Scotty, we need more power…” - so why not create a case with a built in flat battery/powerbank?
For the joke, we need to ping @Skalman (for reasons) 
Looks like they are already working on active cooling at a ‘micro’ scale: xMEMS | Active Micro Cooling | XMC-2400 (at 1mm thick I would probably call it ‘nano’, holy crap). But since it’s meant to actually be on a chip (I think) it’ll probably never even be accessible for “hobby” consumers.
But this is tempting… it even blows air horizontally instead so you don’t need to leave additional space for airflow… I think.
The next joke was going to be that we need a bigger battery… or some fusion reactors or whatever the Trekkies use.
Replaceing the back cover with a bigger battery and some metall for passive cooling. Und some bumper parts…
Piezoelectric case? Of course you gotta wear it while doing Jumping Jacks.
Revision 4
Made a few minor adjustments to increase air gaps even more. Now a full 1mm gap behind the back and “in theory” (but probably not in reality) airflow possible from the bottom opening towards the top openings.
And the really cool part:
A little bit of residue from a previous print near the top, I’ll have to see if I can remove that somehow.
Zero at reality and better to wait GLES3.
Does the camera see the case at all?
I don’t think so, it looked ok in the last version, but I’ll have to check this version.
I think for an active cooling version, I’d need to seal up most of the gaps near the button openings and such (doable I think), and seal up the camera opening with a wall around it so it’s flush with the phone. Otherwise air would be going out from everywhere other than the hot zone/vent where it’d help the most (plus it might be annoying otherwise).
Then the back would need to be significantly thicker. Right now it’s 2mm (case) + 1mm (gap). Even with one of those fans that shoots air out sideways, they seem to be 4mm thick typically. So 4mm + whatever is needed to hold and protect such a micro fan, and the back (plastic) would need to be made decently thin for airflow.
It would go from “thicc case” to “CaseZilla”, but it does seem 100% feasible. The issue for me would be powering it somehow. My dc electric skills are mediocre at best and rusty on top of that.
Doing a CrafCloud print of it $13 FDM TPU
No it doesn’t!
This latest version of this hard thermal shielded case has been in some light use for a while, and I think I’ll do some tweaks. I tried some thicc USB plugs and found some that need a little more clearance to insert properly.
And also I’ve found that I want the case to be a little harder to take apart. Phone cases are usually super annoying to take off, but the reason seems fairly obvious… we don’t want it to come off during use.
So I’m going to try reducing the clearance on the pegs for a tighter fit, and abandon the ‘clip’ style plugs which are so small they usually end up breaking anyway (3 out of 4 failed). Hopefully I won’t have to do anything fancier and that’ll be the final revision after some more testing.
A old friend and I invented a plastic that self-cools… We aren’t ready to bring it to market, but it can be set in a custom form… Preliminary tests had allowed it to be heated to 200C and it cooled down to 90C and back down to ambient within three minutes total. Whereas another plastic we tried did not meet those results.
CrafCloud worked amazing and is currently my go-to until I can get the material my old friend and I made patented.
I might finally be getting to a “final” version of this hard case that’d be easier for others to print too. The old designs all relied on extra steps you had to do in the slicer (and maybe some proprietary printer features too), and the connection method was never quite perfect.
I know it’s not a CAD application, but Blender has worked out nicely for this. Turns out I think Blender’s Geometry Nodes are going to solve most or all of these connector problems (this would’ve been too much hassle without geom nodes to auto-generate the cutouts in the top, including some fit tolerance). The round peg connectors that relied on friction to secure the case are now gone. Instead I added rectangular pegs on the sides, and some specially designed interlocking click-fit tabs which definitely hold the case on better. No more potentially fragile pegs which can break off.
So it’s more of a clam shell connect design now. Fit the top half of the case into place with the bottom two tabs. then you rotate the top half down to close the phone in like a clam shell. The top tab holds it closed along with two smaller side tabs to prevent the sides from flexing.
In theory, anyway. 
I’m printing a potentially final prototype with the side tabs for the first time now. The only real flaw left is that the sides flex a little, but I think the new tabs will stop that.
A shame this took so long, and probably nobody needs a case anymore, but maybe someone else will find it useful once it’s done - which will hopefully be fairly soon. Probably one of the most ridiculously over-engineered phone cases ever… 
Good morning,
looks great! If you have the feeling it’s ok, I’ll try a test print and give it a go and let you know.
