SD Card Case

Just bought a new mirror less camera and needed something to store my SD cards. I was going to take the easy way and just buy one off Amazon. Then I thought…wait, I have a laser cutter! Maybe I can just make one. This is what I came up with. Uses small magnets to keep it closed. Works better than I thought it would.




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Classy practical cut.

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Hmm are magnets a risk with SD cards?

(Some googling)

Apparently not. Carry on.

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Had the same thought. I experimented and found no negative effect. So, I think I’m good.

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This is great, very handy!

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Sweet!

So cool. And you can layer up as many as you like.

Geek alert :warning: - just for those interested in the technology.

As an educator of-sorts, but also an EE who has worked with EEPROM (reprogrammable ROM) since the 80;s, I looked into how it works, and I’m over-simplifying here.

A transistor turns on or off based on a “gate” voltage. In and out (source and drain), a very tiny input to the gate can control more “flow” between them.

But how do you store data?

There are two gates in a flash memory transistor. One is insulated from the other, called “floating”, and can store electrons indefinitely (*when new). It can, however, be charged or discharged by using a much higher voltage - which is (often) applied between the source and drain. *(This process eventually breaks down the insulation which is why flash memory has a finite lifespan.)

So how do you read the data?

Think of the floating gate as a bucket of water on a see-saw, alongside a similar but empty bucket. There’s a weight on the other side, heavier than either bucket when full. If the floating gate bucket is full, filling the regular gate bucket will cause the see-saw to tip. If it’s empty, it won’t. The “normal” gate can be energized and if the floating gate is full, the transistor opens, current flows. If the floating gate is empty, the transistor stays off.

The difference from the bucket of water analogy is that “testing” or reading the data doesn’t permanently store electrons in the regular gate.

Fun stuff. For me (as a geek) at least! :face_with_open_eyes_and_hand_over_mouth:

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Great idea.

I really like how this came out! Very classy indeed. I like all the thoughtful thumb areas. And I’m a sucker for any design with embedded magnets.

What a cool variation on a gift card holder!

Nice! Much better than all the little plastic cases I have lying in various drawers all over the house!

Great idea!

I need to make something for all of my CF cards and filters. I would also like to make some type of storage solution for all of my gear, where it keeps everything visible and handy but then I can easily hide it away so my daughter doesn’t get into it. She likes to randomly carry things around the house and then put them in various spots. lol I haven’t decided if she is like the little girl on Signs where she leaves glasses of water everywhere and eventually they are going to save our lives, or what. (She also puts play silverware, especially knives, inside her toy purses, so I guess she’s ready for anything. LOL)

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Haha! Sounds like you have your hands full! This was pretty easy to make. I used 5mm magnets that are supposed to be 3mm thick, but they are a little shy of 3mm, or, the wood I used is slightly thicker than 3mm. I haven’t checked with my calipers yet. Anyway, those little magnets are plenty strong to keep the case closed.

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