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The RPi camera uses a cable that looks nearly identical to a flat flex cable.

enter image description here The regular RPi Camera connector. enter image description here The Pi Zero adapted version.


I have seen videos of people folding/creasing these types of cables. (Source) But I do not know if this is okay to do with the RPi Camera's cable. Could this do harm to the cable and cause it to not work or be unreliable?

The reason I need to fold/crease it is because I have a project in which a Pi Zero is almost touching the walls of it's casing, so the cable only has about 0.5cm of space between the Pi and the wall.

EDIT:

At about 1:50 in this video he states to not make kinks in the cable, but he does not provide any reason for this.

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  • I don't think folding is the est idea, a few pics of the Pi in your enclosure (including height) may help us make some better suggestions. May 21, 2016 at 3:17
  • @SteveRobillard I do not have the new Pi Zero yet, but when I do I'll be sure to edit my question. May 21, 2016 at 3:18
  • What case are you using? May 21, 2016 at 3:23
  • @SteveRobillard I don't have a picture or a link at the moment but the dimensions are 7cmx11cmx3cm. And the Pi is sitting parallel to the 7 cm side. It isn't an option to put it parallel to the 11 cm side due to the battery and other components in the box. May 21, 2016 at 3:25
  • if you have some vertical clearance you may be able to mount the pi on an angle. May 21, 2016 at 3:42

3 Answers 3

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We often get this sort of question at picademy when people want to use a camera module with something like an Explorer HAT (which doesn't have a hole for the camera's ribbon cable, so it winds up getting very-nearly-folded as it exits the CSI port). The answer is it usually works fine.

Here's an image of the sort of thing I mean. This is a V2 camera module's cable getting squished under a RasPiO Pro HAT (but still working happily):

folded camera cable

However, how many times you can fold it back and forth before you break it ... well, that's down to your luck! In other words, with your situation (a case forcing the cable to make some uncomfortable turns), I wouldn't expect there's an issue as I assume the cable won't be repeatedly folded or bent, but if you're continually installing and uninstalling the camera, you might want to buy some spare cables!

5

All flex cables have a minimum bend radius, under which a specified number of fold-unfold cycles is guaranteed. This radius depends on the brand, but generally it's around 5-10 mm. Here's a spec for AWM 20941 flex cable from JUDD WIRE, which is sold on Amazon as a Raspberry camera accessory:

enter image description here

As you can see, you can bend it at a right angle with a raduis down to 5mm, and slide back and forth 10000 times, or fold it 30 times with a 5mm radius, or 100 times with a 1 cm radius.

What happens if you bend it with a smaller radius is not specified. In practice, this means that the cable may break sooner, or even instantly. It may also work, at least for a while. This is the same as neglecting any other rating: powering the Pi with more than 5.25V, heating it to above 85 degrees, operating at 100% air humidity etc. Of course, the fact that you only risk a $1 cable makes it less of a problem, if your project does not require high reliability and you can always replace the cable when it fails. Otherwise, I would stick to the spec.

And don't be fooled by flex cables you see in a laptop which are bent at very sharp angles down to 1mm radius. Those are likely to require special conditions during assembly, e.g. pre-heating the cable to 80-100 degrees C before bending. You won't be able to manually assemble laptops at home with the failure rate of an assembly line.

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I know this topic may already be dead but I wanted to add my own insights into the issue.

I have seen this cable in several laptops and even a phone I pulled apart, once. In each instance, this type of cable was folded in order to get the other end to a different area of the device.

As previously stated, you do not want to bend the cable in one direction today and then re-bend it in the opposite direction tomorrow as a nature of most (if not all metals) is the metal will fatigue at the bend point and eventually break. Case in point, take any piece of rigid metal that can be bent and bend it. Now bend the metal at the same point in the opposite direction. Now keep reversing the bend back and forth over and over. Eventually the metal will break.

Conclusion; as long as you only fold the cable once or twice (once recommended) in the same spot you should be fine.

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