Cutting a hole in the hull

[snowleopard]

Re: Cutting a hole somewhere else

Beyond around 4" a hole saw is too much for a domestic drill, you'll need to hire one. As long as there is 2" clearance behind the material you want to drill you can use a jigsaw. If there isn't enough space for the saw to rotate you can use a padsaw. When sawing GRP use a metal cutting blade.

 

[Lakesailor]

Re: Cutting a hole somewhere else

Like Duncan says, the cabin sole isn't going to sink your boat, as long as you've enough space beneath to drill or jig-saw. A jig-saw would be best, but depends on your power options (Mains or battery). The inspection hatches for dinghies normally have a decent lip and you could Sikaflex it down as well as screw. I have one in my cockpit sole and it doesn't really create a hazard, but under a carpet would it be a bit bumpy? (assuming you have a carpet).

 

[Stemar]

Re: Cutting a hole somewhere else

I cut a hatch in my cabin sole using a jigsaw (metal cutting blade). I was able to get a reasonably neat hole and I then attached (screws + epoxy) a 1" ply lip all round underneath to which the piece I cut out is screwed using captive nuts and machine screws.

I made the hole big enough (about 10" X 8") to get an arm in to clean up 35 years of oil leaks and it's made no noticable difference to the panel's rigidity. It's a bit agricultural, but it works and under carpet it's invisible - and no lumps!

BTW. If using a hole saw to cut a hole in the hull, I'd start from one side and go about halfway through then finish off from the other side. You'll get a neater cut that way, with no splintering.

 

[TheoSr]

Re: Cutting a hole somewhere else

For a really "large" round hole I once used a Dremel with the router attachment and a 3 mm cutter. 150mm diameter no problem for this setup. Use a carbide cutter to cut the fibreglass. And beware of the dust, it is not what your lungs prefer.
Keep smiling,
Theo.

 

[Katouf]

Re: Cutting a hole somewhere else

I was working on 50mm to the inch when looking at the sizes available in the earlier link. 150mm divide by 50 = 3inches. QED or so I thought. Hence the post.

I knew it was 25.4 to the inch - just another senior moment.
The trouble is they're coming more frequently these days. Hey Ho!
Alan

 

[Katouf]

Re: Cutting a hole somewhere else

Hi Jim
Nothing but two areas that look like they've been filled in with car body filler; one near the cooker area and the other port side next to the engine tool box (the bottom step).
I think I need to put a hatch roughly in the middle of the cabin floor. Can you see or feel any strengthening webs running fore and aft through your little hatch?

How's the carpet lasting out in the fore cabin?

Alan

 

[jimbouy]

Re: Cutting a hole somewhere else

Alan,

I also have the two filled circular dips that you describe....I thought they may be to do with different layouts.


The existing little hatch is near the aft table leg and no stringers or strengthening are apparent.

The carpet has stayed stuck and I am pleased with it (There's one bit where I could have cut it better, no one else has noticed it but I know it is there) I still have to cover the bulkhead and deal with the underside of the fore deck, but there is never enough time.

I hope to pop down soon..... I have just had new upholstery made and want to see how it looks.

Cheers for now


Jim