Mystery box fibreglassed into the hull of a Fairline 27

[al terego]

While fitting boat legs to the side of my 30 year old Fairline Targa 27 I noticed a 'box' that had been fibreglassed into the port side of the hull.
The box has no wires or pipes running into it, nor anything on the outside of the hull. It sounds solid when tapped with a hammer. It's about 12 inches square and 4 inches high, there appears to be be a second, flatter, box under it.
I hope I've managed to attach 2 photos. We are looking vertically down into a bay between the fuel tank and the port side of the hull ............ the side hull is at the top of the pictures, the fuel tank at the bottom, the bow to the right and the engine bay bulkhead to the left.
So what is it? The only idea that I can come up with is that it's ballast, put in at some time in the past to correct a list. If that's what it is then can I safely remove it ........ which would help to cure a slight list to port that the boat has now.
Has anyone got any other ideas?

https://flic.kr/p/2oPbLVv

https://flic.kr/p/2oPdJWL

 

[simonfraser]

part of en engine room support beam that protrudes forwards to the right of the pic ?

 

[stelican]

I have seen similar ballast bonded in on larger Fairlines so could very well be.

 

[al terego]

A good idea but I don't think it's an engine room support beam because .........
the mirror bay on the other side of the boat doesn't have either box
and it's difficult to see why the engine bay transverse bulkhead would need such support

 

[CliveF]

have you got a metal detector or stud finder you can pass over it ? that will at least let you know if it contains metal.

 

[Daydream believer]

Drug transportation void.
Every posh MOBO needs one

 

[al terego]

good call on the metal detector, I'll give it a go.
The only thing that makes any sense is ballast - lead/concrete. Ultimately, I think that I'll end up drilling into it to confirm that. Followed by a bit of careful chiselling to remove it.
I'll let you know how it goes.

 

[stelican]

Fairline fitted lead ballast in that era.

 

[Tranona]

good call on the metal detector, I'll give it a go.
The only thing that makes any sense is ballast - lead/concrete. Ultimately, I think that I'll end up drilling into it to confirm that. Followed by a bit of careful chiselling to remove it.
I'll let you know how it goes.

Why would you want to remove it? It has been there for a long time and obviously for a reason.

 

[SC35]

Be careful: opening the box could reveal a shrunken Hans Solo encased in Carbonite.
In which case the full force of the Empire could be heading your way soon.

 

[al terego]

Why would you want to remove it? It has been there for a long time and obviously for a reason.

Presumably the ballast was installed before delivery (on the port side) to correct a starboard list.
Now the boat lists to port. It's noticeable when viewed from astern and is about 3 inches difference between the sides.
There is no obvious reason for the list and no simple fix. The only significant additional weight on the port side is the calorifier and it would be impractical to try and move it to starboard.
On a previous boat the list was caused by water leakage into the hull core on one side, but this boat has had a recent (clean) hull survey. I know that surveys of fibreglass hulls can never be 100% fool proof, but any further testing (and repairing) would be uneconomic. So I'm just going to treat the symptom by removing the ballast.

 

[colhel]

Have you tried ballasting the other side to see how much weight is needed to make it level? 3" seems (to me) too much for that size box to make enough difference on a 27 footer.

 

[al terego]

Have you tried ballasting the other side to see how much weight is needed to make it level? 3" seems (to me) too much for that size box to make enough difference on a 27 footer.

You're right, a bit of experimenting is required.
3" is the difference in the waterline heights on the 2 sides of the hull, so only 1.5" to correct it to level.
My plan is to see the effect of removing the ballast completely and if that's not enough then to put it back on the side of the hull.

 

[al terego]

I meant: ................ and if that's not enough then to put it back on the OTHER side of the hull.

 

[Parabolica]

Have you tried ballasting the other side to see how much weight is needed to make it level? 3" seems (to me) too much for that size box to make enough difference on a 27 footer.

I personally wouldn’t advise removing it as it was there for a reason when new. And If the boat has developed a list since new it would be better to try to understand why that could be before trying to remedy it in this way. Then if remedy is still required, just add counter ballast instead of removing what has been part of the hull for so many years.

 

[henryf]

Fairline fitted those in case of an emergency. Crack it open and there’s 2 bars of Kendal mint cake, 4 tea bags and a copy of Razzle.

 

[V1701]

What side is the steering position on, i.e. when someone's sat there does it list more or less?

 

[LittleSister]

You're right, a bit of experimenting is required.
3" is the difference in the waterline heights on the 2 sides of the hull, so only 1.5" to correct it to level.
My plan is to see the effect of removing the ballast completely and if that's not enough then to put it back on the side of the hull.

First try putting on the opposite side (a) an equivalent weight to your estimate of what it could contain if it is ballast (which would be similar in effect to removing the supposed existing ballast), and then (b) double the estimated weight (which would have similar effect to moving the supposed existing balance to the other side).

You report the existing box as 12" x 12" x 4" = 576 cubic inches. According to an online calculator, a block of lead that size would weigh 107 kg = 236lb = 16.8 stone. So find yourself (a) someone about 17 stone to stand on the opposite gunwhale, then (b) two people of that weight, or say three of 11 or 12 stone.

 

[stelican]

What side is the steering position on, i.e. when someone's sat there does it list more or less?

I think your onto something there pretty sure double helmseat to stb

 

[DAKA]

Why would you want to remove it? It has been there for a long time and obviously for a reason.

Agreed, surly you can find some other carp on board that you can chuck over the side before trying to remove that, looks an awkward area to work in.

we have had our boat for 20 years now and have tons of stuff we have never needed

5 fire extinguishers for starters
a steel tiller ( if the hydraulics go I can stand in the back with a tiller that weighs 1/4 ton, can’t see where I am going down their anyway.
3 x air con units ( in the UK !!!!)
gas cooker - who ever cooks on board
gas hob
horse shoe life belt
life raft
flares
dive gear
spear gun
kedge anchor
loads of batteries and all marinas have 240v anyway so one would do
80m of anchor chain when 40 would do
dinghy oars
dinghy anchor