Very soft stretchy rubber grommets, where from?

I need to 'near hermetically) seal a cable where it passes through a panel without removing its moulded-on connectors.

Ideally a 'Polo' mint soft rubber washer is stretched over the connector which is then passed through a shouldered bore, on either side of the rubber ring are pairs of 'D' shaped blocks (thick washers cut across the diameter). End pressure is then applied so that the rubber sandwiched is compressed so that it seals on the bore and on the cable OD.

I know my soft/stretchy' description is like a piece of string but normal 70 Shore O rings are far to hard and probably would not stretch to suit a cable of 5mm and a connector of 20mm dia. On examples I have seen the rubber is more like Jelly Babies, if anyone remembers those!

Googling for soft rubber rings is likely to lead one astray! so I'm hoping someone here might know of a suitable source.

Ian P

Have you thought of splitable cable glands there are a few manufacturer's here's one https://www.icotek.com/en-uk/product-catalogue/cable-glands/

David

I think I know the type of thing you are looking for but for the life of me I can't name them.

In the meantime is there anything suitable from this grommet company....

**LINK**

Could you use self-amalgamating rubber tape?

Ian , have you considered making some moulds and using a potting compound used in the external cable joining process. I think Srewfix sell it. Certainly TLC do.

Some formers (like shuttering for concrete pours) and an elastic silicone sealant?

Ian, can't find it on screwfix site but magic gel on the toolstation site might do the trick.

Perhaps a normal grommet, cut through on one side and super glued once in position?

Surely the process by which you get the cable through the panel without removing the connectors should allow you to fit a normal cable gland at the same time? 😉

Maybe this 'mouldable glue' would do? **LINK**

Why not mould a grommet in place using a silicone based putty like Sugru or Kintsuglue?

Neil

Tried the cut a normal grommet and superglue suggestion from Speedy Builder5. Worked for a while but after a year or three the glue came unglued. Not sure how long it actually lasted. Know it was fine after one year but noticed it was unstuck after three.

Probably do better with the special glue supplied with split CV joint gaiters and similar flexi-rubber under car duties.

When dealing with small bonding areas and less than rigid substances correct glue choice seems to be the secret of success. Trouble is the right glues seem to be expensive and / or hard to get. Even when they claim to be suitable for difficult materials the consumer, blister packed, versions don't seem to be anything like as effective as the real thing.

My success rate is something like 1 in 3 with ordinary consumer glues on difficult materials. 100% when I've been able to lay my hands on the right stuff.

Clive.

Some good suggestions, thanks all.

Picture is of an existing 'Pass-Thru' that is used on underwater camera housings, some used at depths over 100m and the housing and contents might be valued in tens of thousands of pounds so failure and leaks have to be avoided.

The rubber ring shown is one that split when stretching. As supplied it has a bore of about 6mm and an OD of 20mm. Because this particular camera is made in different lengths the sealed joint needs to be re-makeable to suit the cable on a particular setup.

The one shown is a standard commercial item so this size is not a problem, what I am trying to do is custom make some to suit very small (1.5mm) diameter cables that have 12-15m diameter connectors moulded on both ends of the cable.

I suppose that more important than the hardness of the rubber, is its stretch-ability, I have never used Sugru or similar products but it seems unlikely to me that its unlikely to have the properties of common or garden elastic bands, which is a bit what the ring shown feels like.

Ian P

Castration rings might fit the bill?

could you possibly cut a slice from a soft rubber hose such as this

**LINK**

or the bull...

I'll get my coat.

Ian,

A while ago, I was recommended to try Bentley Advanced Materials : **LINK**

https://www.benam.co.uk/products/silicone/

These products may be ideal for your application

[ they were a little costly for my immediate need, but yours is in a different league ]

MichaelG.

Suggestion:

Use a silicon rubber ring. Compress it by a washer with chamfer. (Ideally without having to cut the washer. )

Bolt the washer to the panel so that when the fixings are tightened they compress the silicon rubber to seal against the panel and against the cable.

Howard