Catalac 9m Hull Damage

[sonerai]

I am considering purchasing a late 70's Catalac 9m which has incurred some hull damage, (from 'slamming' - allegedly, though looks more like grounding?). There are several small deep cracks (7 or 8).
Is the inside of this area, which is the forward part of hull between the pontoons on the 'ribbed' area accesable from inside the vessel?

My concern is that water ingress may have damaged the upper deck supporting structure,wood,fibreglass etc.
If access is impossible what are your thoughts on a long term repair schedule.
I am a proficient engineer and diy person but have little experience in structural fibeglass repairs (though have read and watched a lot of information). Any useful comment welcomed.

[Pete7]

Hi and welcome to CF

The good news is yes it is repairable and I would suggest buying the west system manual which will explain all and enable a DIY repair.

Can't answer the specific questions because I haven't been on board a Catalac, however, unlikely to have damaged the deck. More likely will be water damage to bulkheads lower down but until you go on board you won't know for sure. Even if they are wet, it is all repairable but do make sure it's going to be cost effective. In other words will the costs and epoxy isn't cheap plus your time give a good return on the purchase against buying one which doesn't need the work.

So GRP and epoxy repairs all quite doable by an owner. Note however, new GRP doesn't stick to old GRP, hence the recommendation to use Epoxy not GRP resin and CSM. Epoxy can be used only with fibreglass cloth not CSM.

Pete

[simonmd]

Hi and Welcome from a new Catalac owner!!

I've recently purchased a later 1994 Catalac 900 and in my search, came accross a few of the older 9m models that suffered from this. It is indeed from 'slamming' and is not unusual. We have a forum member who has personal experience of this, 'boatman61' but he's not available for a couple of weeks as he's presently aboard my very own Catalac, delivering it from the UK down here to the Med'. He delivered a 9m a year or two ago that ended up with the same damage en route, it was repaired at a boat yard relatively easily I believe.

I've attached a pic that shows the damage once the surrounding area had been cut out....

[Unicorn Dreams]

Welcome Aboard Cruisers Forum.

Send Tropicat a PM. he;s the Catalac expert on the site.

[Unicorn Dreams]

My mistake, it's Tropic C at

[simonmd]

Or Talbot, another guy with alot of Catalac experience.

[sonerai]

Hi, Is it possible to access the inside of the damaged area?..
I am keen to move forward with this boat..(at the right price naturally) and am awaiting the last survey from the agent.
Thankyou for all your assistance everyone.

[simonmd]

Directly above that area is the anchor locker so i'm guessing that access would be possible from above.

If you can afford to wait a couple of weeks, I can have a look at my own 900 and give you a better idea.

[sonerai]

I noticed on the 9m the rudder to skeg arrangement seems wrong..what should the gap be (in cms)..and should rudder extend below skeg. I will have new rudders fabricated and wa swondering on the best material..steel,glassfibre with core/solid, aluminium , glassed plywood etc. I presume an airfoil section would be best. I have read and noted the catalac skeg fitment problems and should the skeg extend to the transom?..Any thoughts anyone.

[Talbot]

First, the under-hull damage. This should be relatively easy to get to in the forward part as it is under the anchor locker which goes back to the bulkhead at the foot of the forward bunks. I suspect it is harder to access from above when you are under the bunks themselves as I think that this is a seperate moulding from the bridgedeck, and I have no idea what is between the two mouldings.

AS for the skeg/rudder thing. This is a common fault on Catalacs. The skeg is merely glassed onto the bottom of the hull, and was done after the hull was removed from the mould. I have seen lots with big gaps between rudder and skeg and this really impacts the effectiveness and streamlining of the system. On my boat, I added a piece of wood and then glassed over the whole in order to minimise the gap to the point that a barnacle could not get a hold!. The skeg was designed so that it was the same length as the rudder, and the bottom of the skeg has a stainless fitting which is the bottom rudder pivot. It is common for this fitting to show crevice corrossion. The fitting is also through bolted on the skeg, and it is also common for this to allow water into the skeg - which is fibreglass over a wooden centre. The skeg and the rudder are the two most common areas for a catalac to have osmosis damage. When dried out, a catalac with skegs will actually sit with significant weight on the skegs and rudders such that the rudders may not turn! This is normal!

The strength of these skeg rudder combinations is well beyond what you will find elsewhere, however, their very strength means that they provide a lot of resistance to water flow and wetted surface.

The Catalac (8 and 9m) also have a recessed flat point just forward of the skeg, moulded into the hull. This is the mounting point for the P bracket for the shaft drive. If you dont have a shaft drive, make sure you fare this off as well, as it is another source of underwater drag.

[Tropic Cat]

Ian

My boat has the new rudder design where the rudder is fixed. The rudder is hinged directly onto the skeg.

Mark's experience in this design and his solution should be noted!!

[boatman61]

Hi... the damaged ribs are made up of closed cell foam and are meant as stiffeners... they are not accessable from inside but are relatively easily fixed... just cut back to a clean bit then fill and fair... but you can be sure at the next bit of serious slamming they'll re-appear.
You could always remove them entirely and replace them with wood batten stiffeners....