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STRONGBACK DISCUSSION etc.
113 needs a new beam and since Ebb has broke the mold I think we're going to laminate a new beam similar to his. Fortunately for me, I have a friend that is well versed in the ways of wood. He's laminated everything from fishing nets to display cases to full blown foot bridges. He also finds my anxiety regarding this piece humorous. To him it's just another arc, but as we all know it's the backbone of our beloved little craft. So we've done some research and mixed his experience with a little nautical input. Here is where it has to end up. One of the previous owners did a repair(hack) job on the area NEAR the mast step but not really. As far as I can tell all they did was cut out the cabin liner in that area cut through the inner skin and then glue it back in completely cockeyed and unfair. Off by a strong 3/16":mad: Not to mention that the inner skin is still mobile under the step. So we'll put in our strongback and main bulkhead first and then go topside and finish the job.
p.s. I know-I know the plywood head liner doesn't look original. But it's stuck really well to the fiberglass so we'll deal with it. Actually it may facilitate in adding handholds forward.
strengthening the strongback
I was thinking of doing the repair recommended in the manual where you add steel plates to either side of the beam under the mast. Where I didn't see any bowing there before, or very little, it seems to be more pronounced now.
But I have lots of questions.
I guess I don't really understand why adding the plates would strengthen the strongback--they wouldn't really be resting on anything so they wouldn't actually bear any weight.
I met someone who did this on an Albin Vega but he recommended strongly that you not jack up the beam first, because of all the unknown stresses you might inadvertently add. He just added the plate to the beam as it was. Any opinions?
I pulled off some of the formica around the beam to see what was under there and I'd like to keep going with taking it off but it continues behind the lockers. Any suggestions for how to cut it flush with the top surface of the lockers? Also, I've been warned against doing this, the part I took off came off very easily but I guess if some of it is better adhered you could actually damage the bulkhead. Opinions?
also, I found three bolts already going through the beam--is that normal?
Robin
Mischief #44
Strengthening the mast support, strongbacks etc.
Thanks to Bill for your continuing efforts and to Dave (marymandara) for your efforts to discover and or produce masthead replacements and rudder shoes etc. Rather than respond on that thread in the "General - Off Topic" forum, I am asking for this new one on the topic of "Strengthening the mast support, strongbacks etc." in this "Technical forum"
My big technical problem right now is serious structural damage to the mast support area and strong back caused by a recent accident, and also a damaged mast head fitting. I have looked at the Association Manual and various threads on this site in regard to reinforcing or augmenting the strongback, and finding the necessary parts. The information seems to be spread all over, but the available information is incomplete.
I have found and reviewed photos of the main salon side of stainless steel plates added to the strongbacks in Sirroco and Orinoco Flow, but would be interested in shots of those installations from the forward cabin and also photos and text descriptions of approaches taken by others to deal with mast compression and mast support issues.
I had no personal issues in this area whatsoever, until two days ago, but in a harbor tabernacle-related accident on July 28th, my mast was driven downward and aft into the deck thus cracking the laminate or solid section under the mast clear through to the cabin liner. A previous owner unstepped the mast and modified the deck section with epoxy in time past in a manner which will not be clear to me until destructive testing has been initiated. I imagine that I may have my hands full shortly.
I have not been able to determine the extent of damage to the masthead fitting. It took the brunt of th eimpact, but transferred much of the force down the mast into the deck.
Just knowing that new mast head fittings may be available soon is very helpful to me.
I fear that the repairs may be both expensive and costly time-wise.
It would be nice to have all of this information in one thread on this forum. So if you all see fit, I could use some photos and words of advice in this area.