Fitting a new floor

[rando]

The last couple of days Ive been helping a mate Prepare his boat for new floors.
We have removed all the old stringers and prepared the hull for new stingers but need some advise on fitting tanks.
We have a couple of options open to us.
We have a 150 litre SS tank out of a yacht, but would need to check it into the stingers on both sides, and the centre stringer would only be 150mm deep.
By the way the hull is a 22 ft Blisscraft.
Or two 65litre rectangular tanks but these would require a raised floor forwrd of the centre console.
Or would bladder tanks be a better option.
Would some of you guys care to offer some advice on the best ( most cost effective way to go.
Cheers
rando

[FNQCairns]

IMO probably not worth changing the good structural design of the boat for a stainless tank if it can be avoided, bladders if they are still the same as when I researched them are not a good idea for petrol, diesel would be OK, the volume in each is a consideration also.
There are some good enough underfloor plastic tanks coming onto the Oz market I noticed.
Also don't discount GRP tanks they are considered to be one of the best if not the best tank material, there are many fitted to larger ships in service around the world, some boats have the fuel tanks glassed to structural componets and the boat ie the hull makes up the bottom of the tank as does the stringers/bulkheads for the walls, been done for 10s of years and is an accepted practice in boat building for those that understand the material.

cheers fnq

[FNQCairns]

I also have a PDF which has some GRP tank building info (it's also on the net somewhere), should you want it PM your email, if I find it I will send.

cheers fnq

[rando]

Thanks FNQ,
sent you a PM.
Very interested in learning more about that GRP option.
Thanks again
rando

[rando]

Can anyone tell me where to look for underfloor tank suppliers
cheers
rando

[smiley_doobinator]

Could I grab a copy of that pdf please? fitting out a 5M fibreglass runabout with a shallow floor and this may solve all my tank problems.

[SO70]

i would determine how much fuel you want, then modify the stringer and bulkhead layout to suit.
i did this to a 6m Haines.
ended up with 300litres in one aluminium tank under a removable floor.
fibreglass tanks are best left to professionals.
i have seen plenty of fibreglass tanks fail.
as for making a tank that is part of the hull, stringers etc, what happens if you get crap in the tank and need to clean it out.
how do you get into it.
aluminium tanks are strong and relatively cheap, and can be removed for cleaning if necessary.

[rando]

Thanks Guys
FnQ, thanks got your pdf, havent had time to read it yet
Smiley D,Ill send it to you later when I get a minute