Tiny cracks in the Tetris Microcard acrylic

I noticed that my tetris microcard had some tiny hairline cracks around the threaded inserts, but none of my Arduboys have the same (even the ones I disassembled several times).

So, I think there is a different assembly procedure, or the material of the MicroCard is different because even in some random YouTube videos I can see the cracks:

Does your unit has the same hairline cracks around the bronze threaded insert?

PS: Not a critic to @bateske or anything, in fact my unit was free (don’t look a gift horse in the mouth), just a small observation so he can check what is going on with the assembly/production.

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I just got mine and yeah, they are around the screws. Unfortunately, there was dust on the inside, right in the middle. Not what you want to see when you first get it. I took it apart and cleaned it.

Everything is working now. I can live with the cracks. Hopefully they don’t grow, which I don’t think they will.

Mine has the same kind of cracks. the ones in top and bottom right are the worst. My best guess is that the holes in the case where too tight for the inserts or slightly thicker inserts where used then originally intended. Other then those hair cracks the case is perfect.

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Those threaded inserts are part of the injection molding process, so I am more prone to think on another source of the issue:

  • More fragile ABS mixture (harder than the one used in the Arduboy, and less prone to scratches)
  • Over tightening while assembling and/or not perfect alignment on the new faceplate mold
  • other?

I just looked more closely. I have very tiny cracks on the left side screws, but larger on the right side screws. As in your pic. I just got it, so hoping extended use or pressure won’t open them up.

If it is the acrylic being weaker, I wonder about the run of the arduventure units.

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ahhh, just learned something new :slight_smile: there’s more to injection molding then shooting in some liquid pastic into a mold.

I thought the case was made of polycorbonate. Maybe thats it, they used ABS instead of polycarbonate?

Added detail: while the hair cracks are the worst in the top and bottom right with mine. it’s the least in the top left.

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I have nothing like those cracks a few swirl marks and tiny scratches but nothing like you posted

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Great to see it’s not an issue with all of them. Only my Arduboy has such clean molded inserts.

BTW I’ve added an image of the left side in my earlier post.

I checked my original arduboy and yeah, everything is clean.

I hope the next runs of arduboys can sort out this issue if it’s something that can be fixed on the manufacturing line.

Not sure what the percentage is…

I do not know really, I said ABS by mistake. I guess it is probably acrylic and not polycarbonate, nor transparent ABS.

http://www.unisteeltech.com/fasteners/threaded-inserts.html

I also learned something new, molding them in is only one way to do it. :smiley: so… your guessing could be right too.

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Yours looks flawless, maybe it is from a different batch?

I can see that the holes are not perfectly aligned, that is why I am thinking the issue is a new plastic mix, harder one, but brittler

Unfortunatly these cracks are on a large percentage of the second production batch of Microcard.

These threaded inserts are placed in the mold during the injection process. If we would have seen the cracks at this stage we would have caught it during quality control.

However the polycarbonate plastic we use for the front cover shrinks ever so slightly, about 1 to 2% after being molded, and it can take more than a month for this to happen.

So these units were assembled and we only started to discover this defect after opening up the packages. It’s been a decision to ship the units anyways as it would require scrapping an entire production batch and it’s only a minor defect.

That said, if you do have a problem with your unit in specific please use the contact form to reach out to us and we can try to resolve the issue.

The good news in all of it, is that we have been lucky knock on wood that this issue does not effect the Arduboy. As to a resolution? Well we actually don’t have current plans to produce any more Microcard so the only thing we can do is try to help people out on a one by one basis.

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Sadly this does affect the arduboy. Large scratches and sometimes cracks appear after a day of use. I am planning to print a new front cover for my arduboy because of this. Could you possibly add a thin screen protector to new batches? Or add a solid color w/clear screen part option?

You’d have to be using it fairly aggressively for that to happen, and haven’t even seen any cracks to speak of. It’s all relative to how you use your technology. I’m way more careful with my cell phone than my arduboy and even it has a giant scratch on it after the first few weeks.

The new Arduboy packaging includes a scratch protector but it covers the whole device. You could cut it down to just the screen if you wanted. Other users have mentioned success in using screens intended for pebble smart watches.

We’re always looking for solutions but unfortunately for this issue where it happened after it was already packaged… a judgement call had to be made.

And again, if you do have one of these defect units and have an issue with it then let us know, we’re here to help!

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Alright, maybe it was a hyperbole. But I can’t stand having a whole bunch of scratches appear when I shine it in a light. There was this large one in on the screen and one I could feel at the bottom of the screen and plenty of even smaller faint scratches that appear when light is shown on them now.

And WHAT!?! A screen protector? Guess I got a earlier production because I just go a arduboy and a cable.

@bateske is referring to the clear sticky backed plastic wrap that all Arduboys including kickstarts shipped with

It does not. Look the pictures carefully, these are internal cracks. Can you post a photo of your cracks?

I have my units in a Ziploc bag… I think they are way tougher than you say they are.

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The GuardFilm protector I put on mine is still holding up well.

Oh, you were talking about internal cracks? Whoops I thought you were talking about scratches on the outside.

Here are some images of my arduboy anyway with the annoying scratches that appeared on my screen after a day of putting it in my pocket or on top of my computer.