Glueing SD cards into XO laptops

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Glueing SD cards into XO laptops

Adam Holt-2

As many thousands of SD cards are now being considered to be retrofit into legacy XO's, in quite exciting new experiments with content-packed OS's, Kevin Gordon is way ahead of us all as usual:

What glues do people recommend, to reduce temptation from young kids who fidget/grab anything they can?

Can we come up with the best glues/brand-names/techniques to mitigate this very real problem, that small objects wander off, in small hands especially?

Also a somewhat more permanent glue is desired by many schools I talk to, who face a very real risk of overt theft, as 32GB or 64GB SD cards represent a week or a fortnight's salary for a teacher/janitor in many of the countries where we work :-(

The equivalent in NYC (where an increasing number of teachers are paid $100,000+/year) might be to leave $4000 gold coins on every student's desk, and to very naively/pretentiously expect none will walk :-)


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Re: [UKids] Glueing SD cards into XO laptops

Kevin Gordon Gmail
Adam, we tried silicon over the slot applied from the inside, not glue.  :-)  Cards fail, and removing them once the case is off, without causing damage, was also a 'use case'.

What ended up being a more reliable method to prevent theft, was not using micro-SD's in adapters, but only full size cards.  Then, one educates the students that the cards have great value in the machines, and because of their size and 'formatting', virtually zero use outside of them.  Manually monitoring the machines state also works when they are used mainly in classroom settings and are 'assigned' to specific students.  Very few of our user base have the ability to quickly take a case apart, or know how to repartition cards that use unix file systems.  Since there are also few devices in the environment which can take a native full size card, the trouble to steal them, is usually more than it's worth.

Depending on your user stories, to quote the vernacular, your mileage may vary.

KG



On Mon, Mar 21, 2016 at 10:32 AM, Adam Holt <[hidden email]> wrote:

As many thousands of SD cards are now being considered to be retrofit into legacy XO's, in quite exciting new experiments with content-packed OS's, Kevin Gordon is way ahead of us all as usual:

What glues do people recommend, to reduce temptation from young kids who fidget/grab anything they can?

Can we come up with the best glues/brand-names/techniques to mitigate this very real problem, that small objects wander off, in small hands especially?

Also a somewhat more permanent glue is desired by many schools I talk to, who face a very real risk of overt theft, as 32GB or 64GB SD cards represent a week or a fortnight's salary for a teacher/janitor in many of the countries where we work :-(

The equivalent in NYC (where an increasing number of teachers are paid $100,000+/year) might be to leave $4000 gold coins on every student's desk, and to very naively/pretentiously expect none will walk :-)

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Re: [UKids] Glueing SD cards into XO laptops

Adam Holt-2

On Mar 21, 2016 10:48 AM, "Kevin Gordon" <[hidden email]> wrote:
>
> Adam, we tried silicon over the slot applied from the inside, not glue.  :-)  Cards fail, and removing them once the case is off, without causing damage, was also a 'use case'.
>
> What ended up being a more reliable method to prevent theft, was not using micro-SD's in adapters, but only full size cards.

What about gluing MicroSD's into its sleeve/converter that very often is included in the original purchase?

Essentially building a full-size SD card out of a MicroSD.

Not our first choice, but the reason we are forced to consider this hack (despite our distaste for sleeves/converters that sometimes fail) is that full-size SD's are increasingly harder to procure --  as these are no longer mass-market items: the increased price of full-size SD's can (sometimes) destroy viability.

> Then, one educates the students that the cards have great value in the machines, and because of their size and 'formatting', virtually zero use outside of them.  Manually monitoring the machines state also works when they are used mainly in classroom settings and are 'assigned' to specific students.  Very few of our user base have the ability to quickly take a case apart, or know how to repartition cards that use unix file systems.  Since there are also few devices in the environment which can take a native full size card, the trouble to steal them, is usually more than it's worth.
>
> Depending on your user stories, to quote the vernacular, your mileage may vary.
>
> KG
>
>
>
> On Mon, Mar 21, 2016 at 10:32 AM, Adam Holt <[hidden email]> wrote:
>>
>> As many thousands of SD cards are now being considered to be retrofit into legacy XO's, in quite exciting new experiments with content-packed OS's, Kevin Gordon is way ahead of us all as usual:
>>
>> What glues do people recommend, to reduce temptation from young kids who fidget/grab anything they can?
>>
>> Can we come up with the best glues/brand-names/techniques to mitigate this very real problem, that small objects wander off, in small hands especially?
>>
>> Also a somewhat more permanent glue is desired by many schools I talk to, who face a very real risk of overt theft, as 32GB or 64GB SD cards represent a week or a fortnight's salary for a teacher/janitor in many of the countries where we work :-(
>>
>> The equivalent in NYC (where an increasing number of teachers are paid $100,000+/year) might be to leave $4000 gold coins on every student's desk, and to very naively/pretentiously expect none will walk :-)
>>
>> --
>> Unsung Heroes of OLPC, interviewed live @ http://unleashkids.org !
>> ---
>> You received this message because you are subscribed to the Google Groups "Unleash Kids" group.
>> To unsubscribe from this group and stop receiving emails from it, send an email to [hidden email].
>> For more options, visit https://groups.google.com/d/optout.
>
>
> --
> Unsung Heroes of OLPC, interviewed live @ http://unleashkids.org !
> ---
> You received this message because you are subscribed to the Google Groups "Unleash Kids" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to [hidden email].
> For more options, visit https://groups.google.com/d/optout.


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Re: [UKids] Glueing SD cards into XO laptops

Arnd Bergmann
On Monday 21 March 2016 11:13:41 Adam Holt wrote:
> Not our first choice, but the reason we are forced to consider this hack
> (despite our distaste for sleeves/converters that sometimes fail) is that
> full-size SD's are increasingly harder to procure --  as these are no
> longer mass-market items: the increased price of full-size SD's can
> (sometimes) destroy viability.

This sounds surprising to me. Looking at a price comparison site, I can
see the following:

* There are about 10% more models of microSDHC cards available compared
  to SDHC, currently 663 vs. 593

* For the larger SDXC cards, the reverse is true, with 199 SDXC vs
  147 microSDXC.

* For faster cards, there are also more SDHC than microSDHC. This is
  particularly important because slower cards are likely to use TLC
  flash rather than MLC, and they will die fast

* Looking at the most common models from reputable manufacturers
  that are available in both sizes:
  - Sandisk Ultra 2015:       SDSQUNC-032G-GN6MA / SDSDUNC-032G-GN6IN
  - Sandisk Extreme Pro 2015: SDSQXNE-032G-GN6MA / SDSDXNE-032G-GNCIN
  - Samsung EVO 2015: MB-MC32DA / MB-SC32D
  - Samsung PRO 2015: MB-MD32DA / MB-SD32D
  in each case, the SDHC model is cheaper than the respective microSDHC
  model, in case of the last one much cheaper (19 vs 26 EUR).

You probably don't want to get any other model than the above ones
anyway, but if you do then make sure that they are comparable in
their performance and longevity characteristics and you are not
comparing cheap microSDHC cards that are only meant for storing
videos to the ones that have a chance of surviving a few months
of use as a normal file system for user data.

        Arnd
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