Advice Required On Cutting A Hole In A Bulkhead

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BlowingOldBoots
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Boat Type: Rival 41C
Location: Hogganfield Loch

Advice Required On Cutting A Hole In A Bulkhead

Postby BlowingOldBoots » Mon Mar 09, 2015 10:09 pm

Hi,

In order to run a new gas line and access a dead space below a locker floor, I need to access the lazaret which I can't do through the lazaret deck hatch as it is too small. My plan is enter the locker space by cutting through from the aft cabin via the aft bulkhead. I have the construction and design plans for the Rival 41C and this bulkhead does not appear on the bulkhead drawings, so I assume it is not structural and it just separates the lazaret from the aft cabin.

The hole would be approximately 400 mm long by 300 mm wide. Once I have finished the work I will glue in a flange and then glue onto the flange the section that I have cut out. The drawings below show the arrangement of the aft cabin and stern. I am also considering just bolting the cutout onto the new flange bedded on sealant and filling the gap, retaining easier future access. The bulkhead is covered in foam backed vinyl, so as long as the finish is smooth, no issues from an aesthetic point of view. On the drawings below, the oval circle is the bulkhead and the rectangle is roughly the position of the cutout.

On the stern, on the inside of the lazaret is a glassed in web for the back stay tang but I doubt that this bulkhead adds to the stiffness of this area although that is just a guess. The spinnaker sheet blocks are anchored in the quarters just forward of this bulk head but the deck thickness is massive at that point so again I doubt that the bulkhead plays much role in stiffness for the combined loads, however, I don't really know.

Any comments or advice would be appreciated.

Thanks,

Alastair

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BlowingOldBoots

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cpedw
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Re: Advice Required On Cutting A Hole In A Bulkhead

Postby cpedw » Tue Mar 10, 2015 2:00 pm

Before reaching for the jigsaw, I would consider trying to use an electrician's fish to feed a rope or wire through the inaccessible space then using that to draw the gas pipe through.
I can imagine that may not work if the route is at all tortuous. And if you need to secure the pipe at frequent intervals it may not help either. But it could reduce the amount of surgery required.

Derek

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BlowingOldBoots
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Re: Advice Required On Cutting A Hole In A Bulkhead

Postby BlowingOldBoots » Tue Mar 10, 2015 3:47 pm

Derek,

Thanks for the idea and it would help. However it if it was just that then no problem. Unfortunately the old gas pipe was glassed in place through the lazaret sole. The glassing has failed and there is now about 5 gallons of water below the sole which is inaccessible except through a wee hole which I have used to syphon off the water.

I really need to cut a hole in the lazaret floor as well, dry off the void and then seal up again as well as seal the old gas pipe penetration. While I have access I can also hang some wires better such as the stern light, wind generator and put in some reinforcement for a second set of mooring cleats.

Thanks,

Alastair
BlowingOldBoots

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Matthew D. Alvarez
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Re: Advice Required On Cutting A Hole In A Bulkhead

Postby Matthew D. Alvarez » Tue Sep 15, 2020 8:42 pm

cpedw wrote:Before reaching for the jigsaw, I would consider trying to use an electrician's fish to feed a rope or wire through the inaccessible space then using that to draw the gas pipe through.
I can imagine that may not work if the route is at all tortuous. And if you need to secure the pipe at frequent intervals it may not help either. But it could reduce the amount of surgery required.

Derek

Yes, you should not use jigsaw immediately. There are some other applicable options, which I can explain after completely knowing your situation.

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BlowingOldBoots
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Boat Type: Rival 41C
Location: Hogganfield Loch

Re: Advice Required On Cutting A Hole In A Bulkhead

Postby BlowingOldBoots » Thu Sep 17, 2020 9:41 am

Thank you Mathew for reading my post. It was 5 years ago and I eventually rerouted the gas pipe completely different to the original installation and no further hole cutting was required.

My goodness, it is giddy in here, I don't think we have seen such a rate of response for many years now. Please do continue.
BlowingOldBoots

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claymore
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Re: Advice Required On Cutting A Hole In A Bulkhead

Postby claymore » Thu Sep 17, 2020 6:35 pm

if you ever have to resort to hole cutting in the future - I've found a B&D Multi tool to be easier to manage
just saying
Regards
Claymore
:goatd


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