drilling the transom

[lc0021]

I have an Avon SuperSport 4.65 Rib - and I'm fitting a new self draining bailer. I'm considering fitting one a bit bigger than the current bailer to allow for the restriction added by the rubber diaphragm attachement in the centre of the new one - and to help the water get away quicker.

But this means having to drill a new hole (or drill out the existing hole) - however - before undertaking this I want to be sure about what I'm doing...

Does anybody know what the transom is made from (yes - I know - wood...) - what I'm wondering is if it's a solid large piece of wood - or if its some kind of composite material that's bonded together and made waterproof by the plastic coating ??? - and whetehr there's anything special I'd need to do in the process of drilling out the hole and fitting the new bailer sleeve ???

[Orange Beeny]

if it was a falcon it would prob be chipboard!

[TIM]

Originally Posted by Orange Beeny

if it was a falcon it would prob be chipboard!

hahahahahah!!!! I would say it could consist of old rags, paper and floor sweepings

Sersiouly thought


Your transom is mosy likley Plywood.... I would think that inlarging the existing hole would be the best option .... post a picture , and you will get lots of advise ...... You will have to do a A1 fiberglass job over the cut, to stop water getting... this is the last place you want a water leak .......

[Rogue Wave]

it will be made from marine ply and quite thick to probly 25mm plus. You need to get a Holesaw to do a good job. It takes a while to drill out and yo should stop every minute to clean out the waste.


you can get a holesaw from Screwfix.com

if you are drilling out the existing hole then put a thin piece of ply over the hole at the rear so that you have a place for the pilot drill to go to. (i take it we are talking holes in excess of 50mm here!

[lc0021]

Originally Posted by Orange Beeny

if it was a falcon it would prob be chipboard!

Actually - that was exactly my fear....... Is it chipboard ????

Thanks for the replies - you're getting my drift - and the info is very useful... I'll take your advice and post some pics

The transom itself is 40mm thick. The existing bailer is 25mm - and I was planning to go up to 40mm..

I have a holesaw - good tip about using the light sheet on top to get the pilot hole...

The issue is really about sealing the hole.. The bailer fittings consist of a palstic tube with a flange at the outside - will it really be necessary to to a fiberglass job on it ?? or is there another way of sealing the fitting in using some kind of mastic sealer ???

[Rogue Wave]

Silkathene wouls seal it

[Mark Halliday]

This is one I made earlier. Well, the middle of the hole anyway. It was cut out using a 12.5 dia x 60 long carbide router cutter. Hole cutters only do about 35mm and this is 46mm thick. Construction is glass laminate-19mm ply-glass laminate-19mm ply-glass laminate. Cutting 2 of these holes trashed the cutter.
To pre-empt all you smart Alecs, I could only get to one side, which is the other reason for not using a hole cutter.

I sealed the hole with 5 layers of 50mm woven tape & resin plus a layer of gel-coat.

[jwalker]

Do it proper, like.

There you go....http://www.rib.net/forum/showthread.php?t=5849

[Mark Halliday]

Originally Posted by jwalker

Do it proper, like.

There you go....http://www.rib.net/forum/showthread.php?t=5849

JW.
Some of us like to make life difficult for ourselves.
BTW I liked your method, but decided to do it the expensive (stainless) way, but how do you make the hole?

[jwalker]

Originally Posted by Mark Halliday

JW.
Some of us like to make life difficult for ourselves.
BTW I liked your method, but decided to do it the expensive (stainless) way, but how do you make the hole?

Mark out a PCD with spring dividers, chain drill it with a 10mm drill and tap out the centre. It takes about 2 mins maximum and a ring of holes in wood and fibreglass is nothing to a twist drill.