Noisy masts.

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monroe
Posts: 26
Joined: Wed Dec 04, 2013 6:33 pm
Location: Newport, OR

Noisy masts.

Post by monroe »

The masts on our Freedom 39 DS creak loudly in the roll coming down the west coast. Not sure if the creak is coming from the deck or the step. The step looks to only be held in place with an L bracket, there is no well to drop the mast into and possibly shim.

Am I missing something?

Thanks,

Doug
s/v Spartan, 1983 Freedom 39 DS #27.
Douglas Monroe
s/v Spartan, 1983 Freedom 39 Deck Salon
La Paz, BCS, Mexico

ketch22
Posts: 42
Joined: Fri Dec 05, 2008 5:06 pm
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Re: Noisy masts.

Post by ketch22 »

Hello Doug,

The mizzen mast on Ketch 22 also creaks. It was a common complaint when the boats were new. Some owners in the fleet epoxied the mizzen mast to the step, silencing them completely. It also made them hard to remove. I tried to build a support structure on the outside of the mizzen where it sits on the step. It failed on a return trip from Hawaii. The concept was sound, but I need to beef it up a bit.

Despite the noise, the mast has been a structural success. I have sailed many thousands of miles on open ocean without a failure of any sort.

Regards,

Tom
Ketch 22, F39 Express

monroe
Posts: 26
Joined: Wed Dec 04, 2013 6:33 pm
Location: Newport, OR

Re: Noisy masts.

Post by monroe »

Thanks ketch22, we'll look in to seeing what can be done to further secure the bottom of the mast. I don't want to drill in to the masts for more L-brackets, I do want to be able to remove the masts down the road, I'm thinking box the base of the mast with wood, then glass around it to keep it from moving.

Doug
Douglas Monroe
s/v Spartan, 1983 Freedom 39 Deck Salon
La Paz, BCS, Mexico

ketch22
Posts: 42
Joined: Fri Dec 05, 2008 5:06 pm
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Re: Noisy masts.

Post by ketch22 »

I absolutely agree that adding additional L brackets is the wrong way to proceed. I'm not even convinced that the first one is a good idea because it focuses the force of any mast movement on a very small (relative to the size of the mast) piece of the overall mast base.

Building the box is the approach I used. It worked great for about 1500 Pacific Ocean miles (from Hawaii to San Francisco) before breaking. I think that building a better box (more rounded, a little more robust) would help. I think also the next time that I will use Spartite to fill the gap between the mast and the box. It's not so rigid. It will allow a small amount of movement, as it does at the mast where it enters the deck. They also claim that if you use vaseline on the surface of the mast where it touches the Spartite, the Spartite won't stick to the mast, making removal easier.

Are you near San Francisco now? It's a great place to get work done and buy parts. If you plan on make changes any time soon, I am very curious about what and how you do it. Ketch 22 is in Mazatlan right now, but I am in the south bay. If you make changes, I would like to see what you have done if it would be convenient.

Tom
Ketch 22

AlanK
Posts: 112
Joined: Wed Dec 10, 2008 6:59 pm
Location: Freedom 33 Boston, MA USA

Re: Noisy masts.

Post by AlanK »

I have an F-33. I know the arrangement is different but in case my situation provides anything relevant I thought I'd provide it.
My mast fit in a circular aluminum base. They originally had a bolt with threads patricianly filed down through the base into a hold in the mast to prevent rotation. These holes had become oval and the PO had put as oak backing inside the mast. This must have worked for a while but also become oval allowing the mast to rotate back and forth a bit (and creak and abrade the bottom of the mast). I went through a series of attempts to alleviate this. (the mizzen had no problem I guess due to lower forces etc.).
Here is what I have now and has worked including through storms on a Boston to Bermuda round trip.
Added a quarter to 3/8" of glass and epoxy to inside bottom 2 inches of mast and filled existing holes. Redrilled and bolts that screw into aluminum base ends machined completely smooth (and smaller then original).
Spartite at base and at deck level collar (still use original wedge between mast and deck).
Had Garhauer make a custom 2 part (so it can be put on with mast in place stainless collar with rubber compression band (similar to what they do to attach a boom vang to the mast but not as heavy) with flanges for attaching eye bolts each side. This clamps to the mast under the deck.
From the collar I have turnbuckles to strongpoints on each side. This prevents rotation or any risk of mast rising up and down and abrading.

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jamesorr
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Location: Rochester, NY
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Re: Noisy masts.

Post by jamesorr »

I have an F32 (Mull), and had a similar issue with mast "creaking" several years ago. The setup on mine had a "top hat" for the mast step and a urethane wedge/collar setup at the deck. In addition, the mast rotation was checked by a threaded steel rod which goes completely through the mast and fits into a slot in the top hat -- although to be honest, given the tightness of the urethane wedge when fully inserted, it would strike me as unlikely that the mast could rotate much regardless. It was obvious when listening to the mast in rolling seas (the only time the creak was apparent), that the creak was caused by the mast's inside diameter being a bit larger then the present size of the top hat (seem to recall it being approximately an 1/8 of an inch -- although would wouldn't need to be off much for the noise to result). Using some calipers to get accurate measures, I proceeded to build up the bottom 3 inches of the mast interior with epoxy to get close to the existing top hat diameter (didn't take much in my case). This "repair" has made a noticeable difference (i.e. don't even notice them anymore) to the previous noises that used to emanate from my mast on certain sea states/points of sail.

Note, to give one a sense of just how tight the urethane wedge can be, the first time I had my mast pulled, the marina owner relayed that once we had the mast collar unbolted, he could just pull the mast out and the collar would "pop" out -- yeah, right, not... I think if I hadn't stopped him, he could have pulled the whole boat of the the water by the mast only held in place by the wedge. My new marina pulls/re-steps the mast annually so that I can store the boat inside, and once you get the hang of it (and they do), it's a short and painless operation.

Mike Holibar
Posts: 174
Joined: Mon Jun 01, 2009 12:41 am

Re: Noisy masts.

Post by Mike Holibar »

I had the same issue on the foremast. It was moving around the top hat and made quite a noise.

I made a mess of getting it out, destroying the urathane in the process. Second time I put a jack underneath with a piece of
flat bar to push the wedge out. Built up the inside of the mast with epoxy and glass matt. Let cure then coated with release agent. Then I built up the top hat by running dynel tape around the top hat, coming over the top edge by a few mils, then refitted the mast while the epoxy was only partly cured. Have done a couple of thousand miles since then with no further problems.
Mike Holibar
S/V Fyne Spirit of Plymouth (Freedom 39PHS-1989)
Lyttelton
New Zealand

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gamayun
Posts: 225
Joined: Thu Dec 06, 2012 9:14 pm

Re: Noisy masts.

Post by gamayun »

Mike Holibar wrote:I had the same issue on the foremast. It was moving around the top hat and made quite a noise.

I made a mess of getting it out, destroying the urathane in the process. Second time I put a jack underneath with a piece of
flat bar to push the wedge out. Built up the inside of the mast with epoxy and glass matt. Let cure then coated with release agent. Then I built up the top hat by running dynel tape around the top hat, coming over the top edge by a few mils, then refitted the mast while the epoxy was only partly cured. Have done a couple of thousand miles since then with no further problems.
Mike, I hope you're still on this forum. How many layers of Dynele did you use on the mast step? I see it swells much more than fiberglass mat so was also wondering if by re-installing the mast before it the Dynele cures and using the mold release agent, if this was sufficient to keep it from becoming permanently attached to the mast? Anyone know? I haven't worked much with fiberglass.
Kynntana, Freedom 38

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