450: Creaking bulkheads

[Millerslocal]

Hi all,

Happy to be spending some time aboard our L450 based in Maldives for a few weeks. Have noticed some rather consistent and loud creaking in the inside bulkhead of the rear cabin, even in fairly calm sea states.

Is this a common occurrence, does it stem from any particular area/juncture and how can it be resolved? Just annoying when trying to sleep!

On a less annoying note, any way to resolve creaky floorboards?

Thanks!

[paulajayne]

Talcum powder works will on land based creaks. Give it a try may work.

camera lens puffer can be used to get it into awkward spaces.

[tuskie]

We've had some success reducing creaking by firsly finding the source. This is the hard bit. It's usually the edge of ply cabinetry rubbing on the inside of the hull. There usually needs to be hull flex for this to happen. Sometimes it's best to use your fingertips to feel the vibrations when the creak occurs. Once the source is found, try running a flexible saw blade between ply and hull, or wedging a small piece of canopy clear PVC into the offending area usng a long screwdriver.

Good luck!

[Emerald Sea]

Originally Posted by tuskie

We've had some success reducing creaking by firsly finding the source. This is the hard bit. It's usually the edge of ply cabinetry rubbing on the inside of the hull. There usually needs to be hull flex for this to happen. Sometimes it's best to use your fingertips to feel the vibrations when the creak occurs. Once the source is found, try running a flexible saw blade between ply and hull, or wedging a small piece of canopy clear PVC into the offending area usng a long screwdriver.

Quite right, we've done the same thing as Tuskie finding such creaks and groans. We've tried a few techniques i.e. gently separating the two offending surfaces and inserting baking paper between; applying a small amount of silicon spray; gluing in one side of a thin silicon sheet. Sometimes they are just too hard to get to and we've become accustomed to the noise .

I always do inspections of each bulkhead and elsewhere following a crossing to make sure everything is intact.

Do not attempt applying any hard sealants or screws etc to stop this movement. This will cause more worrying problems in the future.

[atoll]

candle wax rubbed on the bearing surfaces works well or WD40 sprayed on if nothing else available,failing that ear plugs or a valium!

[Snowpetrel]

One old wooden square riggers I worked on creaked very loudly at sea and at anchor in rolly anchorages. It used to get so bad the passengers complained that they couldn't sleep.

We ended up drilling small holes in the offending joints and squirting a small amount of oil into the offending woodwork. This stopped the noise for a few weeks or so, then the passengers started complaining about all the snoring...

[Ulstue]

Apart from creaking of the boom, the davits and lines, I only had one creaking spot, even when there were (light) waves from a certain direction. The bonding of a board to the hull had a crack. It was the board that goes down from the galley, to the right of the fresh water pump and the through hulls of the bilge pumps. I asked my dealer what to do.
Lagoon recommendes to cover the seal with fiber and resin 2 x roving 500/300.

It is difficult to reach the board - a shipyard wanted to remove the cabin for the work. I did it myself without dismounting the cabin, it was uncomfortable but also no big deal.

[Millerslocal]

The cause of the offending creak is in the port main cabin - where the small walkway is between the bed and the interior bulkhead. It only creaks when one is on the bed. No-one on the bed, no creak.

It seems to be where the elevated floorboard on the side of the bed meets the internal bulkhead. Standing on this floorboard resolves the creak. There doesn't appear to be sufficient space to wedge anything in to the very small visible openings. It almost looks like the floorboard has pulled out every so slightly from the vertical cabin side.

The small gaps visible on the creaking side are not visible on the non-creaking side - see attached images. There doesn't seem any way to lift or re-position the floorboard as appears fixed in.

The creak is really loud - even earplugs aren't sufficient!

[UNCIVILIZED]

Can you use a suction device, like a toilet plunger, to grip the offending panel & lift it out. Then shave a bit off of the edge & put it back in place? Or even round the edge & stick on some teflon tape. The stuff that's used in dinghy centerboard/daggerboard trunks. As of last check they have it at APSltd.com

FYI one way to find the source of such noises is to use a stethoscope with a directional wand on it's end, instead of the normal piece which the MD presses against your chest. Some guys still use them old school style for tuning engines.

[tuskie]

Originally Posted by Millerslocal

The cause of the offending creak is in the port main cabin - where the small walkway is between the bed and the interior bulkhead. It only creaks when one is on the bed. No-one on the bed, no creak.

It seems to be where the elevated floorboard on the side of the bed meets the internal bulkhead. Standing on this floorboard resolves the creak. There doesn't appear to be sufficient space to wedge anything in to the very small visible openings. It almost looks like the floorboard has pulled out every so slightly

Eureka! You've done the hard bit; finding the source of the creak.

Now it's relatively easy to stop it. This creak seems to NOT be caused by cabinetry rubbing against a flexing hull, instead it seems to be just two pieces of cabinetry rubbing together. Most Lagoon plywood cabinetry is glued and screwed. This makes a secure and quiet joint. Sometimes the glue breaks and the join can move slightly, creating noise. This happened to our nav station cabinetry after a long and rough passage.

Some suggestions; confirm the source by gently wedging in a thin knife blade. This should stop or quieten the creak. And perhaps separate the two pieces that are rubbing. A quick fix is to wedge in plastic or, as "Uncivilized" suggested, teflon tape. A better cure is to re-glue. On our nav station, we used waterproof construction adhesive ( sold locally as "liquid nails"). This product is slightly flexible and may be forced into the separated joint. On the inside of these joins, out of sight we reinforced where possible by gluing and screwing in timber moulding. I'm not sure if it's possible to access the underside of your noisy joint.

Good luck and quiet nights.

[UNCIVILIZED]

One other possible cause, as mentioned earlier, is that creaking bulkheads can be indicitave of tabbing which has broken/broken free. So that the bulkhead is moving with the motion of the boat, & rubbing on the hull, thus causing the noise.

[DavefromNZ]

I had the same problem as Ulstue and L450 owners I suggest you have a look as is common. We used something similar to sikaflex and 15 months later still good. We got at it from the bedroom side as well as water cupboard :

[Matt Johnson]

Originally Posted by UNCIVILIZED

FYI one way to find the source of such noises is to use a stethoscope with a directional wand on it's end, instead of the normal piece which the MD presses against your chest. Some guys still use them old school style for tuning engines.

Since I can't imagine many cruisers have a stethoscope aboard, a hose held up to your ear is enough to control noise direction and find a sound.

Matt

[Seaqul]

What exactly did you use "something like Sikaflex". I have had trouble finding something that stays bonded to Lagoon's grey goop used to glue the panels to the hull, especially trying to bridge a 15mm gap.

[Millerslocal]

Thanks so much for all the advice thus far - much appreciated.

Have some temporary success by wedging in two pegs between the gaps in the offending cabinetry - floorboard and sidewall.

Am not sure how to successfully fix it using sikaflex as can't access that area from the inside - and it will look unsightly if applied externally.

Any thoughts?