Chopping a Big Hole...

MASH

N/A
Joined
8 Mar 2004
Messages
2,188
Visit site
I need more gas bottle storage on my Sadler 32, and if the spare is not to live on deck I need another locker.

Plastimo sell a neat locker that requires a hole cutting about a foot square.

Now, I know the Stafff Answer is "Dont, without consulting a Surveyor", but...

Is a hole this size likely to materially affect the structural integrity of the boat if it is put in the cockpit towards the rear, ie within the sweep of the tiller?

Is this a Definitely No, or a Maybe, or an No Problem?
 
Provided the area doesn't carry too much structural load and in cutting the hole you leave plenty of 'meat' around it you should be OK. The lockers themselves have some structural strength. I have fitted one and have no concerns about it. The Sadler is a strong old boat so you should be OK. If not sure have a word with a friendly boat yard.

Yoda
 
Shouldn't be a problem if it is in the cockpit side f'rexample. All such apertures on my Westerly are well glassed-in around the flange from behind, which no doubt returns strength. Also cutting out of the middle of a panel is better than cutting through the edge of one.

I would be most cautious about fixing it near the rudder tube / rudder bush / pintles area. This area is designed to take massive latteral loads and is not to be butchered without careful consideration.
 
Think about rudder loads and also the transfer of backstay loads.
Cutting a circular hole is preferable to some other shape.
Chamfer and radius all holes and edges.
Glass in the box properly ( and vent overboard )
Build up the structure with a full ring of glass to transfer any loads around the rim.
Dont use too much glass - 4 or 5 well wetted, chamfered, voidless ( no air pockets ) of roving are many times stronger than 20 layers of poorly laid glass.

Make good the deck with built up layers of gelcoat, sand back and polish.

A 'proper job' should be a benefit to the boat when done!

Ian
 
Top