Case Improvements and the keymat

[levi]

Yes, it's done for these prototypes as well as the first few batches I expect, but that doesn't mean it can't be improved for later batches or as improved cooling which could be sold as an upgrade to existing users down the line. Yes, it's acting more as a heat pipe than as a radiator with all of its fins. Having it act as a radiator is difficult for me to visualise, because I can't easily visualise how the air flow would run especially with the unit in various different orientations. I guess that's not uncommon for handheld electronics, and even different desktop PC cases orient the motherboard along different planes, but nothing I can think of has such tight and tortuous apertures to try to filter through, if we were to consider the hot air convecting within the shell. But I guess any hot gases are likely to escape the unit from one of its many little orifices in quite short time, so it might be worth considering a radiator type of heat sink.

One thing to note which is not explicit in that design, it looks to me like it's designed to contact two sockets which are liable to be at different depths. A flexible strip can handle that with relative impunity, but a rigid block of aluminium with or without vanes would need to know the exact dimensions in that third dimension as well.

 

[Bernd]

I think you might need to update your understanding of laser cutting. These days apparently they have lasers that are so powerful that they don't work by the thermal method of heating stuff up and melting it, they actually smash the electrons off the atoms, such that they can cut transparent materials like glass apparently now.

Source: https://www.bbc.co.uk/programmes/m0002z2z

Im not talking about things which are possible in labors.
Im talking about laser cutter which the one I write programs for.

And the main thing is not if its possible.
Its about if its cost effective.
Its possible to cut copper an brass with conventional laser cutters.
But you need special lens protection methodes and special vapour sucction systems to ged rid of the toxic fumes.
And everytime there is the word "special" in manufactury, its expensive.
Its not good to choose a manufacturing methode because it sounds cool.
You have to choose the available methode which gets the job done at the lowest costs at aceptable quality with the needed quantity.

 

[Yogurt]

Secondly, the Pyra cost A LOT MORE MONEY than planned

How much we talking here ED?

 

[JDTAY]

Why even ask? Unless...

Yes, I see it now. ED receives a mysterious package containing half a million euros and a cup of yogurt...

I would do the same with a slice of pizza, but I gotta win the lottery first.

 

[EvilDragon]

This sounds like not a good idea at all. Nobody will miss the 1.5mm more heatsink (can you quantify the difference this makes?) vs adding yet another supplier and fail mode, extra cost, extra risk...

Not necessarily. The heatsinks I bought look like they were actually cut from a way wider "heatsink-stick" (no idea how to call that properly)
So like they produced a 1m x 15mm long heatsink and then cut it into small 15x15mm heatsinks. Or maybe the even produced a 1m x 1m heatsink and cut this into the small ones. You can clearly see that, as the fins on the heatsink aren't always fully symmetrical, some are cut in half

If we find a company that produces them, it would be easy to cut them simple 1.5mm longer
[doublepost=1554558814,1554556922][/doublepost]

Hi everybody,
I don't know if it's useful, but in France it's a specialist for adhesive cutting, they could make a tool for special form, just send a plan and a quantity
www.adezif.com
Let me know if you want I can call them. I have a bit of time since June, so why not if I could help this amazing pyra project ? I guess you already know that in France it's always weird especially in industrial stuffs
Not hesitate contact me if it can help...

Thanks a lot!
This looks like it's what I'm talking about:
https://www.adezif.com/adhesive-tape-die-cutting-possibilities

I'll discuss this with the case company first, maybe they have some other idea.

Sealing: @EvilDragon if You could please post here a .dxf (or any vector graphic, it's no big deal to convert them) to describe the shape of the sealing, or at least tell us the inner and outer size of a rectangular approximation, then starting monday I'd be happy to volunteer and ask around moderate-sized print houses, ad agencies and metal shops about cutting it mechanically, by laser, or stamping it out.

I need to create that first, as we still need to think aobut the best way to do this.

Heatsinks: if You have a design or a general idea and +/- dimensions, then why not share it? Forum users could show it around and who knows, maybe there is a cost- and time- effective source somewhere in Europe.
Here, particularly close to the German border, a lot of small and medium companies live off exporting such components like Pyra's and logos or heatsinks to Germany, I sure can ask around here and others can ask at their place.

I used 13x12mm with 5mm height ones.
These seem to be pretty standard. The ones I got are these:

As you can see, it certainly looks like it was one large heatsink that was cut into pieces at one side. That's why the fins are rounded on one side while they look cut on the other side.

But I'll check for the perfect size.

Logos: Do we have all the logos already or just some sample ones? I am freshly unemployed and taking it easy this week on job hunting still, so for me it's no problem to send a dozen inquiries here and there or even drive around and ask around personally this week.

We have a company already, just seems we need to provide them with the proper material (aluminium with self-adhesive).

That's already being worked on

ED posted some pictures of it on the last news thread, such as

He attached an alleged dwg file from which you can apparently get dimensions.
Edit: I managed to install librecad and view it in that. Apparently the width is from -22.87 to +41.18 so a total of 63.1mm wide or thereabouts.

The DWG is in mm size, which you need to provide to the software when importing.

That is the design for MOVING the heat away from the CPU to the heatsink.
It's 0.2mm thick, it's this material:
https://www.digikey.com/products/en?keywords=1168-2068-ND

The company is from Asia, so in case you know a company with a similar product that can do custom die cuts here in Europe, you can also let me know

How much we talking here ED?

Quick guess: Approx. 150k - 200k.
[doublepost=1554559083][/doublepost]Quick update from the case company:
They played around with some materials today, but it looks like the discolorizations and shrinks come from the mold surface and can only be covered a bit depending on the material being used.
Transparent works better (what's why you don't see anything like it with the transparent cases), and semi-transparent works okay, but still has some issues:



That's a semi-transparent oceanblue material.

To fix this, we'd need the copper anodes (which aren't usually provided with the molds, as finished molds shouldn't have these issues anymore).

We're trying next week to get the copper anodes from the previous company as well, as then we could properly fix it.

At the same time, the new company is also looking for different workarounds to solve that issue!

We're at it!

 

[JDTAY]

150k - 200k? So what's that, another 1000 Pyras on top of the original 3000 estimate you need to sell to profit?

 

[elw3]

To fix this, we'd need the copper anodes (which aren't usually provided with the molds, as finished molds shouldn't have these issues anymore).

I would to have more information about how they work on that case. Like how can they even work on already finished moulds? I understand you can drill stuff out without much problem and may weld some small parts in but this tweaking sounds like a lot of tinkering and adjusting in a solid steel block which i would have assumed to be unpractical.

 

[Arkay Firestar]

Quick update from the case company:
They played around with some materials today, but it looks like the discolorizations and shrinks come from the mold surface and can only be covered a bit depending on the material being used.
Transparent works better (what's why you don't see anything like it with the transparent cases), and semi-transparent works okay, but still has some issues:

View attachment 32442

That's a semi-transparent oceanblue material.

Please please please, ED, whatever you do, don’t go for a coating or paint. I’m totally ok with discoloration or shrink marks. What I don’t want is another handheld that I have to baby because the paint comes off more easily than nail polish.

 

[netlinker]

I don't like to ruin enthusiasm, but if the link to the used heat spreader material is correct, then it is nowere near a heatpipe. It is material used to increase the interface area between the cooler and the chip. It is definitely not meant to transport heat laterally and will have a terrible thermal conductivity in that direction, as it mainly consists of plastic and not copper.
A heatpipe has a cavity filled with a soaky material that is soaked in water and vacuum sealed. That way energy is not conducted by bulk thermal conductivity but by the thermodynamic process of evaporation and condensation. The thermal transport capacity of such a material is only limited by the soakiness of the core of the material and therefore the fluidic flow inside the heatpipe.
I remember a notebook manufacturer using something called "vapor chamber cooler" which was actually a flattened out heatpipe. I always thought the "Heatpipe" of the Pyra would be of a similar material.
Are there actually thermal conductivity measurements of the "Heatpipe" in use?
I would rather opt for a material omitting the isolation, replacing the isolator(plastics) with copper, as I can't imagine we need the 3.5KV breakdown voltage of the currently used material.

For cutting the material, I would personally look for a company that does foilcuts using either a cutting plotter or a pico pulse laser.
I would prefer the cutting plotter though.

 

[fusion_power]

Quick update from the case company:
They played around with some materials today, but it looks like the discolorizations and shrinks come from the mold surface and can only be covered a bit depending on the material being used.
Transparent works better (what's why you don't see anything like it with the transparent cases), and semi-transparent works okay, but still has some issues:

Interesting that after all the time they tweaked and improved, these molds still suffer from almost the same issues, the Pandora had. General design issues instead of molding issues? Maybe just the wrong materials? Or wrong cooling times for the plastic before it is ejected out of the molds?

 

[Letalis Sonus]

I always thought the "Heatpipe" of the Pyra would be of a similar material.

Do you seriously think that there's enough space for even a small heatpipe? That's a big "nope". We're calling it a heat sink for a reason.

 

[netlinker]

Do you seriously think that there's enough space for even a small heatpipe? That's a big "nope". We're calling it a heat sink for a reason.

If you would've read my post carefully, you would have read, that I suggested changing the material to maximize lateral thermal conductivity (more copper) and not installing a heatpipe, as the currently choosen material is not meant for the purpose it is currently considered.
It could be even more enhanced by changing to graphen foil:
https://www.nanowerk.com/nanocatalog/Nanomaterials/Graphene/details/2917
Though I'm not informed enough if graphen foil is currently available at a reasonable thickness and price .

Ahhh, just informed myself:
https://www.techapps.com/
Sooo, does exist, but probably expensive. Searching for cheaper version ....

 

[EvilDragon]

That material used is a 0.2mm copper with graphite on top and is especially produced to move heat away as good as possible.
It also works, as we've found out from infrared heat cameras (the heat sink heats up more than the processor, so the heat is being transported there).

Why do you think that material is for isolating heat?
Even the Digikey page says it's a copper heat spreader...

 

[EvilDragon]

Interesting that after all the time they tweaked and improved, these molds still suffer from almost the same issues, the Pandora had. General design issues instead of molding issues? Maybe just the wrong materials? Or wrong cooling times for the plastic before it is ejected out of the molds?

Did you read the post?
It's the surface finish that causes the issue. Not the design, not the cooling time, not the material.

Just the surface finish, and that is being created with copper anodes which we would need to fix this...

 

[netlinker]

That material used is a 0.2mm copper with graphite on top and is especially produced to move heat away as good as possible.
It also works, as we've found out from infrared heat cameras (the heat sink heats up more than the processor, so the heat is being transported there).

Why do you think that material is for isolating heat?
Even the Digikey page says it's a copper heat spreader...

Not isolating heat, but electricity (3.5 KV breakdown).
The usage of graphite was not visible in the datasheet, anyway, if it works, it works

BTW: The Heat sink can NEVER heat up more than the processor (second law of thermodynamics) but I know what you mean .

 

[docbroke]

About those surface discolorations and shrink marks, are they seen in black case too ? or they are seen with other colors only ?

 

[EvilDragon]

About those surface discolorations and shrink marks, are they seen in black case too ? or they are seen with other colors only ?

They are heavily visible without any non-transparent material.

 

[levi]

Im not talking about things which are possible in labors.
Im talking about laser cutter which the one I write programs for.

The programme was talking about her success at winning the nobel prize for that work, so I kind of assumed it was done a while ago and might have translated to real shops by now, but I guess if you work for one, you know what you've got at least.

@EvilDragon I like the look of that transparent blue now actually. I'd be perfectly happy if my Pyra were made out of that.

Edit: Yes, and I think I had to tell librecad to treat 1mm as 1mm when I started it up. Did we get the right answer, namely it being about 64mm wide?

 

[Grench]

They are heavily visible without any non-transparent material.

Another thought might be to maximize the current effects being seen so that they are 'everywhere'. Since these are only visual/aesthetic 'imperfections' that do not change the end strength of the product, maximizing them would result in a unique product appearance in contrast to the 'white glove perfection' of so many current consumer devices. Having a crazed surface could be a product advantage as it would hide fingerprints, scuff marks, etc. It would also make every Pyra case have a somewhat unique pattern - with some tendency toward similarity. You showed us a blue jelly-looking transparent case above. Where others might see 'imperfection' I see a naturally occurring sunburst marbling pattern. What does the 'worst case seen' look like in the solid colors?

I'm not sure how many of us expect a polished slate case with perfectly contiguous surface symmetry. Maybe this is one of those details that could take an intense amount of time and money in search of perfection that may not be attainable or even needed?

 

[fusion_power]

Just the surface finish, and that is being created with copper anodes which we would need to fix this...

Sorry, I'm not an ejection mold expert. Didn't know there was a 2. process after the actual molding to tweak the surface. No clue about that.
From the pictues it looked like issue was deep in the case itself. It's good that this seems not to be the case. I'm sure they will solve that remaining issue then.