A rotten mastbeam

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if1038
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A rotten mastbeam

Post by if1038 »

After launching my IF, I decided to disassemble interior to repair and paint it parts at home, in my workshop. But suddenly, I was very surprised with a mast beam. "Oh shiii" - I said, when saw the exploded fiberglass envelope around a beam.
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Plywood got wet for a long time. Once, some years ago, it was swollen and broke its shell. Then it rotted, but no one paid any attention on it. And thank God, I didn't notice it too, when I took the boat from the previous owner: otherwise, I don't even imagine, how was I could to sail from Goteborg to Vyborg, knowing about it all. :lol:
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Today I destroyed old beam. Tomorrow I will manufacture a new beam of steel, and then I shall to install it.
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johan swe-1870
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Re: A rotten mastbeam

Post by johan swe-1870 »

That's bad to find right now when you want to use the boat. :cry:

You way find useful information on changing the beam in this thread: http://www.ifboat.se/forum/22/1583#p7890
It's in swedish, but there are lots of photos when I made a new beam of baltic birch plywood and laminated back to the boat.
Johan Winberg, SWE 1870 InFinit

if1038
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Re: A rotten mastbeam

Post by if1038 »

Johan SWE-1870 wrote:
Tue 21 May 2019 22:24
That's bad to find right now when you want to use the boat. :cry:

You way find useful information on changing the beam in this thread: http://www.ifboat.se/forum/22/1583#p7890
It's in swedish, but there are lots of photos when I made a new beam of baltic birch plywood and laminated back to the boat.
It is not a problem. After demontage of old beam, I understood, what the further work will not be difficult and long - just 2 or 3 days - moreover, I planning to weld an easy to install steel beam.

I already learned your topic up and down in fall, thank you very much. And I have just one question: do you have a front view drawing of the beam? There you posted only top and side view.

if1038
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Re: A rotten mastbeam

Post by if1038 »

Steel beam in progress. It will be attached to the bulkhead by eight M10 bolts and nuts and also glued with epoxy. Under the step I'll attach a wooden spacer with epoxy.
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I has used a lot of similar heavy loaded connections (wood or laminate + epoxy + steel plates + fastenings) on my previous boat and I am quite sure of its reliabilyty.

Erland
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Re: A rotten mastbeam

Post by Erland »

Hi

Class-rules says that the beam must be made of marineplywood. If you dont participate in races, it doesn't matter.
I wonder how you will make the beam fit against the underside deck. Will you use wood? Or are you going to use steel?

It looks like a good job. Looking forward to seeing the final result.

Regards Erland

if1038
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Re: A rotten mastbeam

Post by if1038 »

Erland wrote:
Thu 23 May 2019 05:44
Hi

Class-rules says that the beam must be made of marineplywood. If you dont participate in races, it doesn't matter.
I wonder how you will make the beam fit against the underside deck. Will you use wood? Or are you going to use steel?

It looks like a good job. Looking forward to seeing the final result.

Regards Erland
Hi, I'm not a sportsmen, just a tourist :)

Yes, I'll use wooden spacer, which I could to made from Johan draws. It final height will be selected "by place", after a beam will mounted.

Here is a simple sketch, not in a real scale, where on "A" view - 1 is that spacer of plywood or wood (I dont know yet), and 2 is a filled epoxy:
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Erland
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Re: A rotten mastbeam

Post by Erland »

Hi
Nice sketch.

Looking forward to see the final result.

Regards Erland

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johan swe-1870
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Re: A rotten mastbeam

Post by johan swe-1870 »

There is an article with the dimensions of the mastbeam in Medvind 2011 Nr 2.
Johan Winberg, SWE 1870 InFinit

if1038
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Re: A rotten mastbeam

Post by if1038 »

So, I successfully installed a beam! It's wasn't difficult, but I'm terribly tired. Maybe, it is just too important part :mrgreen:

First fit and glueing by epoxy:
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And after a long uninspiring drilling it ready:
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Spacer:
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And my favorite filler for epoxy - a typical baking flour :)
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