How can I mark micro SD cards in order to distinguish them?

Question

I am aware of the question How can I organize Micro SD Cards?, but don't want to put them in pill box or other organizer.

I want to mark each permanently, so that I can distinguish them - even if a have a few rattling around loose.

I tried Tippex aka Liquid Paper and put 1, 2, 3 dots on a few.

BUT, I use them in several Raspberry Pis

and, when I slid them in and out of the SD card holder a few times, the dots rubbed off. I imagine that the same thing would happen with any SD card reader.

I am thinking of perhaps marking the end that sticks out somehow. The number of dots would be limited - perhaps colo(u)s?

Any ideas for a cheapish way to permanently distinguish maybe 6 to 8 micro SD cards?

Answer 1

My hack is to handle the SD cards only along their edges, to reduce wear on their surface.

I also suggest using a white permanent marker such as this: _{image from Amazon}

Although the can says "paint" the product details describe it as "white permanent ink" so the result ought to be more durable than correction fluid.

There are similar inexpensive brands available, just search for "white permanent marker".

As SD cards get handled a lot, you should de-grease the surface first. There should be room to write a single digit or letter on the case.

---

I have one SD card in a blue plastic case, and I find that lettering with a black permanent marker such as a fine-point Sharpie is reasonably legible.

Answer 2

You could take a look at an engraving pen:

Image courtesy of Amazon

They're like a pen shaped hand held drill, with a fine tip that is diamond abrasive coated. If you lightly make some marks in the case it should be more resistant to degradation from insertion than eg Liquid Paper is

The casing on a MicroSD card is quite thin; don't go too deep. There are a few videos and images around the web of what's inside an SD but there wouldn't be any substitute for taking one of your old dead ones and sanding the case off to find out where it is thickest/where you wouldn't hit any circuits.

Image courtesy of YouTube video "Checking out and watching mind blowing technical design Inside of Micro SD Card

From what i've seen it looks like the best place to grind a few little dots might be the edge that you insert into the holder, on the opposite side to the gold contacts, so that your grindings don't interfere with (bend) the spring contacts on the socket, but there is also a ticker part of the card where you grab it to pull it out, that might just be a lump of plastic with no raised components inside

a coding system that is like binary will count to 8:

Width of sd card
##################### - card 0
#####################

###############   ### - card 1
#####################

#########   ######### - card 2
#####################

#########   ###   ### - card 3 (2+1)
#####################

###   ############### - card 4
#####################

###   #########   ### - card 5 (4+1)
#####################

###   ###   ######### - card 6 (4+2)
#####################

###   ###   ###   ### - card 7 (4+2+1)
#####################

If you don't want to lay out on an engraving pen (probably about $10) you could try a nail file for this applicaiton.. but when yu have an engraving pen they are useful for all sorts of things. Worthy purchase

Answer 3

Most SD cards have a label on one side, the other side is bare plastic. You can mark either with just about anything. I use a fine or medium permanent Ink marker (Sharpie or india ink) to put a number on the bare plastic side.

My Hakuba clam-shell SD card holder holds eight cards. We place empty cards label side out in the holder as we use cards we put the used cards back in label side down. It makes it easy to grab the next available empty card.