Old fibreglass hull - how long do they last?

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It's-Never-too-rough
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Old fibreglass hull - how long do they last?

Post by It's-Never-too-rough »

Hi guys, I'm new to the forum.

I know this could be one of those 'how long is a piece of string' questions as clearly it's down to so many factors such as; manufacturing quality, storage, usage and maintenance.
With that said, is there an age at which a fibreglass hull is past its usefull life? or is beyond restoration to be used for relativly high speeds?

The reason for asking is that I have purchased a 21' powerboat hull which is believed to have been build in the late 60's. I'm considering renovating it, fitting a merc 200 horsepower and useing it on the Irish sea!
Is this a viable proposition? Do any of you use hulls of that age at high speed if properly restored?

Any and all help greatfuly recieved.

Thanks

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Re: Old fibreglass hull - how long do they last?

Post by se7en »

The glass composit will last for many years, however its the wood reinforcing that fails, i.e. transom cores, wood stringers, etc, what make is the boat?

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Re: Old fibreglass hull - how long do they last?

Post by It's-Never-too-rough »

Thanks for your reply.
I do plan to replace the transom core and possibly investigate the stringers. Is it normal to replace all the wood at this age?
I'm not sure what it is and to be honest I haven't seen it in the flesh, only in pictures. I originally thought it was an Avenger as it has the same ski ramp style buttresses as an A18.
However, the previous owner is claiming it was a forerunner to a Marshan called a 'Romney Raider'. The only reference I found to those says they were 18ft 6" whereas this measures in at just under 21ft.

Any clues?

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sean-nós
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Re: Old fibreglass hull - how long do they last?

Post by sean-nós »

Welcome to the forum :drink: Would you be able to post the photos up or a link to them.

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Re: Old fibreglass hull - how long do they last?

Post by It's-Never-too-rough »

Here's the link to what I bought:
http://www.ebay.co.uk/itm/speed-boat-21 ... true&rt=nc

If you look at the picture of the transom it looks a lot like this:

http://wales.boatshed.com/avenger_18-boat-107122.html

which is described as an Avenger 18.

I did get the owner to double check his measurements.

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Re: Old fibreglass hull - how long do they last?

Post by Rapier »

Hi and welcome. It's not an Avenger. It looks very like a 19ft Marshan hull, but I've never seen a deck like that on a Marshan. Is possible the length quoted was LWL. It also looks like the Merc is a long shaft too. Very very rare to find short shaft 80/85 Mercs, most race motors were the '76 & '77 850XS and judging from those survivors they far outnumber any shorty non-XS I've seen. I am extremely short sighted so don't take my word though..

Fiberglass is like any other material, it can fail physically through a number of factors, fatigue / overstress, thermal and residual stress during moulding, etc. The fact that it's been used hard means you need to look closely at the hull if you intend to continue to give it a hard life with horsepower (and weight) that likely wasn't available during it's race career and which might upset it's original design speed and dynamics. It'll really be worthwhile getting someone 'qualified' to check it out, and to bounce your ideas off the powerboat forums, generally they're people who've stretched the envelope.
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Re: Old fibreglass hull - how long do they last?

Post by se7en »

Thats long shaft Mercury on the boat.

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Healey75
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Re: Old fibreglass hull - how long do they last?

Post by Healey75 »

Anything grp is mend-able even if it looks scrap...just depends on how much work you want to do and if you can get it dried out.
Growing up is optional...

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Re: Old fibreglass hull - how long do they last?

Post by It's-Never-too-rough »

[quote="Rapier"]Hi and welcome. It's not an Avenger. It looks very like a 19ft Marshan hull, but I've never seen a deck like that on a Marshan. Is possible the length quoted was LWL.

Thanks for your reply.
The links are to two different boats. The first one is the boat that I now own. They do seem to have near identical deck designs (if you sign up to the website in the second link you can view the rest of the pictures and it becomes obvious they are the same design).

Has anyone else seen one of these? or know what it might be if not an Avenger or Marshan?

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Re: Old fibreglass hull - how long do they last?

Post by solitaire »

One of these came up for sale a couple of years ago with an 80 Merc on the back - I was looking at the time and all I could discover was that she was a "Romney Raider" - made by Romney Powerboats - I think it was 18' 6"......... thats all -- ------- maybe another member may know more about them from this!

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