Fitting a Dinghy Bung

[Seashoreman]

https://www.ebay.co.uk/itm/25615428...3AndUltBRecall&_trksid=p3458402.c101506.m1851
To solve the problem of my little used rowing dinghy constantly filling with rainwater I intend to finally fit a bung such as this example.
I have a metal one in the stern but as the dinghy sits on a launching trolley which is difficult to get beyond the horizontal I figure on drilling a hole where the water settles.
What I am not sure of is how to make sure it is safely and securely attached. The two holes in the example look like countersunk screw holes but as the hull is probably only a few mms thick I cant trust screws. Bolts? But then the nuts attached are exposed to catching on trolley, concrete slip etc. Also what sealer/fix would I use CTI?
Am I overthinking this? Certainly don't want to sink in the middle of the river by not thinking about this though.
(dinghy is in my YC park and only used on occasion as we have a very useful and gratis ferry service. It is big and too heavy for me to put on the racks upside down).

 

[Neeves]

Think outside the box.

We had a similar problem. I scoured Bunnings and bought a plumbing fitting, threaded in and externally, with a flange at one end. The flange allowed me to insert the fitting into an appropriate hole with the flange 'outside'. I could then secure the fitting with a matching collar. I sealed with Sika, don't recall which. I found a bung that fitted the internal thread. I had to use a mix of fittings, horticultural/agricultural and domestic.

I keep losing the bungs - buy 2.

So successful I then invested in 2 more sets for our 200l water tanks to allow me to dipstick the tanks without removing the large spin off access port.

They must come in a range of sizes as the bung is about 1" ID and the dipstick port about 0.5" - or the metric equivalents. All bungs have an hexagonal head.

You can source similar fittings in brass (or bronze) ? which would be more abrasion resistant - but cost more (and be heavy).


Now this is an Australian fudge - where we have no qualms about mixing imperial and metric - we have an inconvenient mix - it might be different in the UK.

Jonathan

 

[oldbloke]

I'm sure self tappers and sealant glue would be sufficient, but if using machine screws then nuts on the inside

 

[tillergirl]

Deck Hardware & Exterior Fittings Scroll down.

 

[rogerthebodger]

Drain Socket with bung | Boat tent caravan awning parts

These have holes for a cord to prevent the bung being lost

 

[B27]

If the hull is only a few mm thick, I would beef it up locally. either lay up a bit of grp, epoxy in a backing pad of some sort?

Keep a spare bung or two, they get 'borrowed'.