Cockpit and hull separation

[mange]

Hi,
My new inspection hole continues to reveal the inner secrets of my Laser.

I have discovered that the cockpit floor has separated from the center beam on the hull aft of centreboard trunk.
The problem is the "putty" which is used to bond the beam and the cockpit floor together - it has cracked/separated all way from front back to the bailer hull joint.
I've taken 2 pic's from starboard/port sides which shows how it looks.
Its hard to see on the pic's that the putty has cracked or separated from the cockpit, the separation is about 2 millimeter towards centreboard trunk.

The putty joint around the bailer seems to be ok, also the "putty" which bonds the aft cockpit corners to the foam stringers in the hull.
The cockpit floor itself seems to be ok - there is no delamination in the grp or the foam core.

What should I do?
The best solution is ofcourse to laminate (glassfibre+epoxy) the cockpit floor together with the beam, but this seems to be a very tricky job and I don't want to open more inspection ports if I dont have to.

Maybe its enough to fixate the front end of the cockpit to the beam - lets say about 10cm?
Then I can reinforce/laminate also over the aft joints - I have an aft inspection port too.
Even if these joints seems to be ok today this can prevent any future cracks in them and compensate for the "cheating" of not laminating along all of the beam/cockpit floor.
In addition, the front corners of the cockpit can be fixated to the foam stringers in the hull - the distance is larger here compared to the aft corners but a spacer made of marine grade plywood and laminated inbetween the cockpit and foam stringer - will this do any good?

A far more complicated method - which laminates/bonds the whole length of the beam - could be to tilt the hull 90 degrees or maybe more, then I can apply epoxi with a roller on a long stick. Then put layers of wowen glass fibre and roll epoxi over. Then repeat with more layers.
In this way I can do one side at a time, once finished starboard, then tilt the hull on port side. The Port side will be even harder to reach - the inspection port is on the starboard side...

I'm sure there is someone who has experience from similar jobs, please give some advice.

I'm familiar with lamination and boat-building work - but not on a Laser yet.

Regards
Magnus

 

[WestCoast]

having never done this particular repair, simply because it's a lot of work for little result, I'm curious what the responses will be.

Anyone have experience or documentation of this very repair?

 

[LooserLu]

...Anyone have experience or documentation of this very repair?

Hi,
there is some hope for a successful repair, no doubt, I think.
Shevy "had" some nice reports about that. He has done a "major surgery
for cracked Laser cockpit sole" to his 134XXX-deathroll-Laser and at a webarchive, the text is available at the maintenace chapter - unfortunately not available: the pictures, that are very important for the understanding of all.

Another text is about a "Minor Surgery for Cracked Laser Cockpit Sole Stringer" and written by Craig Roner. This text may can prove a native of the English language, please. If this text can help Magnus or not I can not decide, until I have not done an intensive translation into my native language, that needs a lot of time for me.
The TLF-administrators know how to get into Shevy's archive.

Personally my opinion is, that the old bondi-glue at Magnus' Laser has to be cut out and an equivalent glue (West System?) may can be replaced there. Therefore another inspectionport maybe is needed at the deck behind the cockpit. I'm not sure how it is possible to cut out the old glue. The area between the floor of the cockpit and the hull-floor is small, maybe is to small for tools. Shevy's method is probably one possible way to cut out the old bondi-glue. Then, the sides of the stinger have to be sealed with slats (or anything else that prevent, that new glue runs out to the sides until the glue is dry enough to hold). If I understand Shevy right, he injects epoxy-resin fom holes that he careful drilled into the cockpit-sole. (Maybe I'm wrong?)
Aft the new glue is dry, the slats are made away and the drilled holes are closed with epoxy and at least gelcoated. Maybe that's a way to process with the repair, I'm not sure.
Good success
Ciao
LooserLu

 

[mange]

I've now got some advises - thanks.
Some of them advise me to remove the old putty/bond first, but this will be very difficult.
The aft original putty joints are ok (bailer and aft corners) so I don't want to remove the brass bailer and break/bend the hull and cockpit apart - and I think I can end up with either more problem or much more work.

Its only the putty between the plywood support beam and cockpit which is separated. All putty is still on the beam (se attached picture 1)

I'm thinking of using epoxi bonding and glue it together. The epoxi must be thickened with a filler until its like mayonaise.

First I'll try to remove any loose old putty, then sand and finally wash with aceton.

I hope I can access and apply the epoxi filler with an putty knife on a stick, maybe I turn the boat upside down so the gravitation will help a bit.

Then I don't know if I should press/force the deck down to the hull support?

My separation has created a gap of 2-3 millimeters (1/10") when the boat is "hanging" in the gunwale. Since the aft corners and the bailer are fixed ok I think this is the "normal" position and pressing the cockpit floor and hull together creates stress in the bailer joint and the centreboard trunk joint - eventually altering the shape of the hull.

Pressing or not - the epoxi filler shall be eased out to a nice radious and will then cover any old putty wich is still left (picture 2).

As a final step (after the epoxi filler has cured) I think I'll put an extra epoxi laminate (woven glass) over the new joint (picture 3).
The lamination will be even more difficult to do - I dont know which method to get the woven glass in place - wet or not?
The glass must be rolled afterwards.
Using shorter pieces (30 cm) of the woven glass starting from the front (where the space is better) might help.

Regards
Magnus

 

[WestCoast]

holy mackeral!

you're going all out on this one huh?

 

[vtgent49]

Hi,

I'll attach a pic of the joint on an '05. The foam seems to have expanded a little more aggressively than yours. This pic was taken before the boat sailed.

This foam/putty was intended as a filler, and not really to bond the two together. Since this is really just a compression joint. I think your filler step is plenty, and the outer glass is uncecessary, but nice. I'd even consider just glass on the easy to reach side.

Re: pressing the two together. The normal use position in the water with your weight on it may press the two together. I'd simulate that, then decide whether to press the two.

Al Russell 182797