# Weight (formally mass)

Discussion in 'Support Area' started by peasthope, Oct 17, 2017.

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1. ### peasthopeStill Fresh

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Has anyone done a weight estimate. No mention in the specifications here or in
en.wikipedia.org/wiki/DragonBox_Pyra .

Thanks, ... Peter E.

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If a model Pyra were constructed out of concrete, that would weigh more.
If a model Pyra were made out of styrofoam, that would weight less.

So - somewhere in between.

3. ### leviStill fresh, damnit!

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It'll weigh a bit more than a Pandora weighs; more CPU boards, bigger screen, much bigger battery. If the battery's made out of the same stuff as the Pandora battery (I think it is) then that's probably the biggest change, and the weight will be proportionally related the the battery capacity in the main. I therefore predict it will weigh somewhere in the order of 320*6000/4220=455g, if wiki's reporting of the weight of a Pandora is right.

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4. ### peasthopeStill Fresh

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A weight estimate is more than a guess. Weights of stock parts are available from specifications. A capacitor or battery for example. For a p.c.b. or die casting, drawings allow calculation of volume. Multiplying by density gives weight. It's an elementary but somewhat tedious calculation. If done properly, the estimate shouldn't be more than about 10% off the prototype weight, ... Peter E.

5. ### leviStill fresh, damnit!

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And you'd rather they do this elementary but tedious calculation instead of getting the electronics all to work, would you?

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When it is done someone will put one on a scale. As is, the last thermal solution looked like it could add 10+/- grams by itself.

7. ### sebt3homebrew player (P. & C.)

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Is that what you're looking for ?

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8. ### BosbeetleTerminally lost

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so about 400 gram okay that's doable.

How heavy was a pandora?

9. ### BinkyDeath's SteedStaff Member

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320g, sayeth the wikipedia article...

10. ### peasthopeStill Fresh

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Thanks sebt3. en.wikipedia.org/wiki/Dragonbox_Pyra If you can weigh the battery alone, that number will also be interesting.

The battery must be used elsewhere. Can anyone give the part number?

Thanks again, ... Peter E.

11. ### TrashyMGSarcasm DispenserStaff Member

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No like the Pandora it's a custom sized LIPO battery, the supplier will make a battery in the size and shape specified. It will likely have a part number EvilDragon designates.

Last edited: Oct 23, 2017
12. ### BinkyDeath's SteedStaff Member

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Like the vast majority of portable electronics, the Pyra has a custom-shaped battery. As trashy says, the part number is whatever ED declares it to be when released.

That said, the battery design will be pretty standard. It's a single-cell lipo with some protection features (maybe a thermocouple? or a fuse of some sort? Similar designs are everywhere.
It's only the shape and capacity that are unique.

13. ### peasthopeStill Fresh

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A proprietary battery is soon out of production. Then a machine
becomes less portable as the old battery loses capacity. I'd prefer
to power by a USB powerbank as offered by Duracell, Poweradd &
others. https://en.wikipedia.org/wiki/Battery_charger#Powerbank The
housing and connector of the computer can be designed to accept more
than one model of powerbank. Then battery replacement is relatively
painless at the expense of a slightly more bulky design. It's a

Regards, ... Peter E.

14. ### TrashyMGSarcasm DispenserStaff Member

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The battery Manufacturer that EvilDragon deals with can make a Lipo battery to any configuration or shape. He can even make another batch of Pandora batteries without issues. Just for reference my First Batch Pandora battery Is almost 7 years old and going strong.

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15. ### BinkyDeath's SteedStaff Member

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The Pyra is already pushing the limits of bulk for a handheld device. Many powerbanks these days use 18650 cells. Including casing, that makes them 20mm thick.
If you want to put a non-specific powerbank inside the pyra, that's going add something like 15mm to the overall thickness.

The entire device would be more than 4cm thick!

Need I say more?

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16. ### leviStill fresh, damnit!

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If I'm taking my Pandora away with me on a long trip I often also carry a decent-sized power bank with me - I also own a third party USB->PSP power cable which is ideal for charging my Pandora from the power bank, either via it's power socket, or it's mini USB socket. You should be able to do similar with the Pyra (although just using a common USB-A to USB-micro cable), and in that case you can even run the Pyra without its internal battery just off the power bank if you like.

You could even make (either by 3d printing, or filing a thick bit of perspex etc.) a thinner bottom slice and velcro attach the powerbank to it. You'd have a cable running to the charge/debug port, but that could be made shorter and less likely to snag.