Repair & maintenance: Rudder has damaged back of boat, help needed ASAP

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Rudder has damaged back of boat, help needed ASAP

Printed From: Yachts and Yachting Online
Category: General
Forum Name: Repair & maintenance
Forum Discription: Questions & tips on the subject
URL: http://www.yachtsandyachting.com/forum/forum_posts.asp?TID=9533
Printed Date: 14 May 25 at 1:02pm
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Topic: Rudder has damaged back of boat, help needed ASAP

Posted By: mattmd
Subject: Rudder has damaged back of boat, help needed ASAP
Date Posted: 21 Jun 12 at 9:20pm

Hi there,

basically with all the pressure on the rudder it is causing damaged to the back of my contender, i have fitted nuts and washer behind to try and spread the load however some cracks have appeared from the pintle moving outwards and are starting to get worryingly movable when the rudder is fitted and I'm worried the rudder could pull part of the back off if it takes a knock or even a rough sail.

Got epoxy and plan to file a v into the cracks and drill the ends then epoxy, to get strength back in the rear before remounting pintle for the rudder is this the right thing to do? or will i need fibres as well?

any tips, ideas really would be appreciated as I need to fix this soon, as the back is weak and will only get worse.

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Matt MD
Contender GBR-620

Replies:

Posted By: JimC
Date Posted: 21 Jun 12 at 9:45pm

What's the boat made from?

Posted By: mattmd
Date Posted: 21 Jun 12 at 9:56pm

GRP i think late rondar contender hull,

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Matt MD
Contender GBR-620

Posted By: JimC
Date Posted: 21 Jun 12 at 9:58pm

Is that cored or solid glass?

Posted By: mattmd
Date Posted: 21 Jun 12 at 10:08pm

not sure my boat number is 620, and is one of the last rondar hull

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Matt MD
Contender GBR-620

Posted By: mongrel
Date Posted: 22 Jun 12 at 7:01am

It's probably best not to use epoxy on it, as that boat is probably polyester. Is there room to get into the tank, remove the pintiles & gudgeons, & glass in a plywood pad. This should stiffen the area around the rudder fittings.

Posted By: Oatsandbeans
Date Posted: 22 Jun 12 at 7:35am

The plywood pad is a good idea, but I would definitely use epoxy for this. Pre coat the wood and bed it into a thickened mix.

Posted By: JimC
Date Posted: 22 Jun 12 at 9:04am

I'd want to investigate this quite carefully I think. Doubtless a piece of ply glued on the back would hold it together for months, maybe years, but if the cracks are right into the main structure as opposed to just the gel coat then I think I'd be inclined to do something a bit more sophisticated. I think maybe I'd grind off the gelcoat over the whole affected region anyway just to see what's going on.

If turns out to be just the gel coat cracking off round the holes wih a bit of water ingress then a ply pad on the back to spread the loads and new gel coat will be good. That will stop water getting into the laminate and promoting osmosis and so on. If on the other hand the underlying fibres and resin are cracking up then I guess cut back to good over a larger area and new fibre and resin right over the whole area. I'd use epoxy I think, not sure that polyester really sticks well to old polyester.

Posted By: Rupert
Date Posted: 22 Jun 12 at 9:13am

I'd go for epoxy, too - there won't be any solvents left after all this length of time. Agree with Jim you need to check exactly what is happening to the structure of the transom before proceeding. It might be that Rondar can help by telling you how the transoms were built in the 1st place.

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Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686

Posted By: mattmd
Date Posted: 22 Jun 12 at 9:18am

i can access it from inside to speak right need to the pintle i have a port hole so can get my hand inside to feel the area. Not sure if its the gel coat that has cracked or deeper. How would i check this?

Allready have large washers on each bolt to try to spread the load

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Matt MD
Contender GBR-620

Posted By: mattmd
Date Posted: 22 Jun 12 at 9:18am

would you recommend the use of fibres along with the epoxy?

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Matt MD
Contender GBR-620

Posted By: winging it
Date Posted: 22 Jun 12 at 10:17am

Hi Matt, this is a common problem on contenders of that age - it happended on 473, the one I had before 620. The most widely used fix is what has already been suggested: a plywood pad coated in epoxy and clamped well on, and big washers. It should at least be accessible through the transon hatch.

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the same, but different...

Posted By: RS400atC
Date Posted: 22 Jun 12 at 10:24am

When I had Contender 471, the pintle was screwed on with self tappers.
When you run a ground with a fixed rudder, something is going to break.
What would you like it to be?

I bolted the pintle and used a lifting rudder.
Plywood for the backing pads is OK, but I prefer to use thick grp sheet.

Posted By: Oatsandbeans
Date Posted: 22 Jun 12 at 11:13am

You don't need to put fibres in the epoxy bonding mix. An ideal mix would be a bit of colloidial silica to thicken it so it doesn't run out from the bond and microballoons or glass bubbles to bulk it out. The laminate should be roughened up with 80 grit and be clean and dry. Try to do a good fit on the plywood to minmise the amount of epoxy required. The wood should have a wet mix of epoxy applied and allowed to tack off before fitting. The end grain will soak up more so give this a second application just before it goes in. Try to get some clamping pressure on the plate if possible with a temporary strut in the tank while the resin cures.

Posted By: timeintheboat
Date Posted: 22 Jun 12 at 1:21pm

Originally posted by mattmd

i can access it from inside to speak right need to the pintle i have a port hole so can get my hand inside to feel the area. Not sure if its the gel coat that has cracked or deeper. How would i check this?

Allready have large washers on each bolt to try to spread the load

Get a digital camera in and take some high-res pictures of the area.

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Like some other things - sailing is more enjoyable when you do it with someone else