Alberg 30 deck Stepped mast Beam

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Windcall
Bottom Paint Application Technician
Posts: 22
Joined: Sun Jan 12, 2020 6:19 pm
Boat Name: Windcall
Boat Type: Alberg 30 1969 Hull 397

Alberg 30 deck Stepped mast Beam

Post by Windcall »

I am restoring a Alberg 30 1968.

I thought I would share pictures of the new Deck Stepped Mast Beam. <br/>
The Beam was cut out and removed and cleaned up. My beam came out with out to much effort, just a little time. I decided that removal and repair out side the boat was both the quickest and cheapest way to do it. I have read of many beams being repaired and all of them seem to really cause more weight and took allot of time and materials. Although many i saw were made from G10 although strong i felt for me it was to bulky and to costly. Sadly my friend Walter passed away recently who was a old timer navel architect from EU then America helped me with this project on paper. I brought this idea to him in a diagram and he ran the ever painful (to me Math) and decided the needed numbers here were beyond original by a huge number. Though I brought to him 6061 Aluminum in my plans and he decided that 5052 was a better choice due to 6061 being susceptible issues with fracture from the pre-bend needed to laminate and from repeated pressures or flexing under sail.

Total cost was just over $250.00 Mat including fiberglass and epoxy but that i have already on hand.<br/>
(3) x 60 "x4.25" x 3/8" 5052 Aluminum Plate
5/4 quarter Sawn Teak x 5'

I have not yet Laminated it yet..or tabbed it in..
I will say the beam came out exact fit. very little to no space between the top laminate and the beam, formed it damn near perfectly, Didn't even need to cut anything to make it fit other than a some tapping with a hammer.</t>
I will however need to sand the top layer of Teak laminate and the lower teak laminate slightly after lamination due to the increase size of estimated 1/8". So 1/16th top and 1/16 lower of sanding to make exact fit.

When i get it laminated I will update the progress.

Just as a comparison my local marine yard gave me a written estimate of 4950.00 to have a beam made and installed. I got a estimate just to get an idea of the replacement cost.
Attachments
beam1.jpg
4metal.jpg
2metal.jpg
Last edited by Windcall on Tue Jan 14, 2020 5:05 pm, edited 1 time in total.
svMira
Master Varnisher
Posts: 104
Joined: Wed Aug 08, 2018 10:16 pm
Boat Name: Mira
Boat Type: Pearson Wanderer 30
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Re: Alberg 30 deck Stepped mast Beam

Post by svMira »

Somebody would be making a crazy pile of money for that yard's price. Wow.

I've never seen aluminum in a wood beam lamination before. The sistering of dissimilar materials has me nervous. But then, up where I live, that beam would be subject to -30C to +30C.

Congrats on the great workmanship. It is just great when stuff works out. Especially when you're dealing with beams that have spring back. I know how good it feels when you get it right. I also know the other feeling, and you have to shape it after the fact. <grin>
Marvin - s/v Mira - 1971 Pearson Wanderer #174
svmira.ca
Windcall
Bottom Paint Application Technician
Posts: 22
Joined: Sun Jan 12, 2020 6:19 pm
Boat Name: Windcall
Boat Type: Alberg 30 1969 Hull 397

Re: Alberg 30 deck Stepped mast Beam

Post by Windcall »

Aluminum to wood with epoxy has a great adhesion value... One has to just prep the metal properly. Tn fact in tear tests it just rips the wood before the epoxy releases.

Rough Sanding with 80 grit, creating slight gouges in the aluminum face to roughen it up.'
Vertical bolting in key areas of the bend to keep the epoxy friction from moving is important.
Also the whole beam will be bolted together from fore and aft sides to the bulkhead.
Walter my friend that was a Navel Designer and gave me the drawings were to place the vertical bolts so as not to affect the areas of flex.
No data to indicate that dissimilar metals issue will be a problem as no offending metals will be in contact. Affect is caused by contact or by some sort of bridge like immersion in water.

Aluminum 5052 is a hardened marine grade aluminum so I've read its used in shipbuilding hulls so don't think it would have to many issues in this application. However I will say .. my Arse and this boat will never see that kind of cold unless there is an arctic age coming you can count on that.

With all that being said, I hope all the studies and work we myself and my Navel Designer friend did is in fact workable!
Time will tell i guess.
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atomvoyager
Moderator | Revitalizer of Classics
Posts: 421
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Boat Name: Atom
Boat Type: Pearson Triton
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Re: Alberg 30 deck Stepped mast Beam

Post by atomvoyager »

Welcome to the group. That beams looks like it will carry the load fine. You may want to add knees under it as in the photo of this A30 I worked on. I've used a vertical placed aluminum plate sandwiched between wood in a beam before on another boat, and while it needs only a single plate it required a larger plate that I had to trim to shape. Either way should be good.
Attachments
68A30Beam01kb80.JPG
Windcall
Bottom Paint Application Technician
Posts: 22
Joined: Sun Jan 12, 2020 6:19 pm
Boat Name: Windcall
Boat Type: Alberg 30 1969 Hull 397

Re: Alberg 30 deck Stepped mast Beam

Post by Windcall »

Adding knees to the beam is in my estimation a very good plan. I know of your past experiences with them from all my reading of your activities. Of which there is many!

My thought when it comes time to that is to actually remove the support on either side of the bulkhead entrance to the V-berth, and add iron wood (As i have a bit of laying around spare) Make a wedge 2" or 2 3/4: at one end tapering to 0 at the full length of the supports attached to the bulkhead. The Wedge behind behind the existing support. Obviously angling the top portion were it meets the mast Beam to make it a nice finished appearance. Then bolt the whole thing through the bulkhead with lightly thickened epoxy.
Currently all four supports for the beam to the bulkhead are only secured by screw, with no evidence of adhesive. Which to me seems inadequate but i guess has lasted 50+ years. Yet when i am out to sea this would weigh on my mind night and day in a blow. So I think epoxy and thru bolted would be more secure.

Just as a side comment Mr Atom! Your work on so many boats I am sure have influenced so many people. I see your ideas popping up all over on many forums... Near word for word. You have given me so many ideas, not always exactly the same as yours but have brought up similar and nearby project ideas. Just know its appreciated! And Recognized!
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