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Would there be a way to replace all the functions of the good ole' cable grip (retaining the cable, providing strain relief, being watertight) with a simple overmolded strain relief ?

I am wondering if a design similar to the image below could be popped out of a hole in a plastic enclosure, would that be enough to provide water-tightness (ipx5) ?

overmolded strain relief

Edit : With a carefully designed hole in the enclosure, the cable might hold in place and provide a seal (like a grommet, but with the left pad preventing the cord being pulled out). I would like to avoid fasteners if possible. (The cable will be secured at the time of installation, so I am not too much concerned about the pull-out force).

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    \$\begingroup\$ Yes, but this isn't a question for this site. Talk to some custom cable shops (can't give specific recommendations here) and they should be able to provide or point you towards someone who can. Expect to pay a couple hundred $ per unit just for overmolding (custom mold machining) in low 10s quantity. \$\endgroup\$
    – vir
    Commented Aug 15 at 1:27
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    \$\begingroup\$ @vir I disagree, electronics enclosures is a grey area between electrical engineering and mechanical engineering. The reason why you can't just let a mechanical engineer handle it is because of things like chassis grounding, EMC and ESD, of which they tend to not have a clue. Additionally, moulding tends to have a severe effect on certain components like potentiometers or inductors, but it also affects RF. So I think questions like this are perfectly on-topic here, given that the purpose is to encapsulate electronics. \$\endgroup\$
    – Lundin
    Commented Aug 15 at 6:29
  • \$\begingroup\$ Thanks @Vir, furtonately the quantity will be around 1000 units so a custom mold is totally faisible. I saw a few of these manufacturers offering molded strain reliefs, but couldn't find one that clearly stated that this could be used for water-tightness. \$\endgroup\$
    – morning_pepsiman
    Commented Aug 15 at 11:31

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Yes this should be sufficient for IPx5 and higher. Noting that IPx5 is just pouring water (rain etc), but this will likely also work for higher IP classes like IPx6 (strong water jets) and IPx7 (one meter under water).

The question is rather how you tighten it to the hole in the enclosure. Things like O ring + nut is proven in use. But if you have 4 screws then it immediately turns questionable and you'd then need some additional means to seal the holes for the screws.

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  • \$\begingroup\$ Nit-pick: IPx5 is low pressure jets from any angle. en.wikipedia.org/wiki/… \$\endgroup\$
    – anon33
    Commented Aug 15 at 7:33
  • \$\begingroup\$ @Lundin I was thinking the overmolded part could be made of low shore rubber or silicone. Then, with a carefully designed hole in the enclosure, the cable might hold in place and provide a seal (like a grommet, but with the left pad preventing the cord being pulled out). I would like to avoid fasteners if possible. (The cable will be secured at the time of installation, so I am not too much concerned about the pull-out force). \$\endgroup\$
    – morning_pepsiman
    Commented Aug 15 at 11:23
  • \$\begingroup\$ @morning_pepsiman Cable glands would be the standard solution in that case. Any reason why they can't be used? \$\endgroup\$
    – Lundin
    Commented Aug 15 at 11:41
  • \$\begingroup\$ @Lundin Indeed! We had that in our first prototype, but our customer did not like the bulky appearance. I must add that the enclosure is quite small, about 2"x3". We also tried using a sealed connector (Deutsh wire-to-PCB), but that too was bulky, and rather expensive. \$\endgroup\$
    – morning_pepsiman
    Commented Aug 15 at 12:07
  • \$\begingroup\$ @morning_pepsiman If you need a compact solution you should probably consider connectors like M12 and the like. More expensive though. \$\endgroup\$
    – Lundin
    Commented Aug 15 at 12:28

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