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20mm Grommets

Discussion in 'Electrics UK' started by canduit, 5 Apr 2018.

  1. canduit

    canduit

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    Are these available in a lower profile than normal ones? eg thinner ones?
     
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  3. Lectrician

    Lectrician

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  4. securespark

    securespark

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    Some 16mm boxes are pre-fitted with a thinner grommet. Worth a try if you have one.
     
  5. mattylad

    mattylad

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    When you say thinner, do you mean the thickness of the walls or the outside diameter of the whole thing?
    I use the above fast fit grommets daily, they are easier to fit, often fall out and do extend further into the hole than a std full grommet.

    While we are talking about grommets, does anyone know of any good fitting tools for them?
    I have to fit them around a 3 core cable then into a hole in a steel frame and sometimes this is extremely difficult, I have been looking for something better than the end of my screwdriver to assist with this.
     
  6. Jackrae

    Jackrae

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    Have you tried fitting grommet onto the hole then feeding the cable through the grommet, which, I believe, is the normal method of installation?
     
  7. Tigercubrider

    Tigercubrider

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  8. ban-all-sheds

    ban-all-sheds

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    [​IMG]

    Remember, a grommet is not a gland. It is to protect the cable from chafing on the edges of the hole. It is not meant to form a seal around the cable, or to act as a restraint.

    If you fit the grommet and then find that the cable won't pass through it easily, then the cable is too big, or the hole is too small.
     
  9. Jackrae

    Jackrae

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    KY Jelly is water miscible, if it doesn't suit the grommet I'm sure you can find other uses
     
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  11. securespark

    securespark

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    I've only ever used it to draw cables in. What else could you use it for?
     
  12. securespark

    securespark

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    Got a picture?
    We like pictures!
     
  13. mattylad

    mattylad

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    Here is the picture as requested.
    grommet.png
    (This is is a particularly rough (as a dogs arse) example of where they go, in this instance I used another leg (which made cable routing far harder) but it shows the path that the cable has to travel.)

    30mm box section that has the cable run up its leg then has to go 90 degrees and out through a hole.
    The hole can only be drilled using a 20mm holesaw, this tends to be a not so neat hole so I have to tidy it up with a rotary carbide cutter thingy.

    Only once the cables have been routed can the grommet be fitted.
    It's even worse when 2 cables have to go through the same hole, this is extremely difficult and cannot be done with the grommet already in situ.
    I am looking for something like a 4mm flat screwdriver with rounded ends, and the tip to be bent 90 degrees like a minature garden ho.
    I'll probably end up butchering an old screwdriver for this.

    Cannot use lube, because A) they wouldn't buy it for me and B) some wonker would pinch it (like they do everything else). (it's that sort of place lol.)

    Anyway, Canduit - did any of the above answers help? or can you explain a bit more on your problem?
     
  14. ban-all-sheds

    ban-all-sheds

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    A punch?


    Why is that?


    Bigger hole?
     
  15. Iggifer

    Iggifer

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    Get yerself some tallow. Nobody would pinch that it's disgusting but it gets the job done.
     
  16. ban-all-sheds

    ban-all-sheds

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    Might greatly upset anybody in the business who is Hindu, and/or lose likewise customers.
     
  17. crystal ball

    crystal ball

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