[Public-list] Deck Beam Repair

Michael Connolly crufone at sbcglobal.net
Sun Jan 2 20:52:13 PST 2005


Alan,
An interesting solution.  I have looked at about 20 boats now that have made variations of the Aluminum sistering plate repair to the Alberg 30 mast beam.  After looking at several boats in the Annapolis area and speaking with many of the Alberg 30 Association members, I discovered that it might not be too big a job to remove the original laminated wooden beam.  It appears to be just bolted in place to the bulkheads.
 
While no one suggested this version of the repair, I am considering removing the beam and taking apart the laminates.  I will make a form to relaminate with new epoxy and then reinstall the beam.  I will probably fill the two holes drilled into the beam for the center mast plate bolts and either eliminate the bolts alltogether or reinstall in a way so to not undermine the strength so much of the wooden beam.
 
I like the look of the original beam and would like to preserve that look if possible.  It took the beam on my boat 35 years to fail.  I believe that if I am careful and achieve an excellent relamination with modern epoxy that the repair will last.
 
Michael  #133

Alan Slater <alanslater at telus.net> wrote:
I'm glad to see the deck beam issue up again. I have wanted to share my upgrade, to get some feedback, as I didn't go the aluminum plate method.
I made a cardboard pattern of the existing beam and had a length of 4" x 4" x 1/4 tube steel rolled to match the camber pattern. I then burned off the top face and discarded it. The forward face was cut off and retained for the backing plate on the forward side of the bulkhead. After a few trial fits to get the right length and angle to match the cabin sides, I used a screw jack blocked to the floor to ensure a tight fit to the beam, and matched the existing bolt hole locations for new 5/16" SS bolts. I also added 4 SS lag screws from the bottom face up into the beam, equally spaced but not above the companionway, to maintain the integrity between the laminations.
After the fit up was satisfactory I had the aft face stamped with the s.n. and then both pieces hot dip galvanized.
On installation I drilled 3/16th dia. holes at the lamination separations in order to inject an epoxy resin sealer well into the delaminations, and bedded the two steel pieces with an epoxy glue of the same manufacturer as the sealer.
I used Industrial Formulators S1 sealer and G2 epoxy glue. I applied positive pressure with the screw jack then tightened the bolts, and caught the drips until the epoxy kicked in.
I used the tube steel for its greater strength than aluminum, and the aft face and bottom were a continuous "L" shape, which I thought would be stronger still. Also the corners of the tube are rounded, therefore no sharp edges to scalp you as you pass under. I did loose a 1/4" of headroom however.The only disadvantage I could see was the additional weight above the water line. The assembly weighs about 45 lbs.
As a matter of interest I would like any comments for or against. But I'm not changing it no matter what.

Thanks
Alan Slater
"Romp" # 358
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