I fully agree.Yeah not quite sure why the expanding foam - by the time you make the beam skins strong enough for the load they shouldn't oil can over that narrow span. But Ian was a clever guy so he must have a had a reason. Maybe holding dimensional tolerances so the sides didn't move in and out when glued together.
As to if it can be repaired - composites are very good at repairability. You just have to be good with a grinder and sander. In this case the only dimensionally critical part is the part of the beam that slots into the main hull notch. So as long as that fits the beam can be slightly ugly/lumpy elsewhere.
If I was repairing these, I'd cut off the gluing flanges in way of the damage, clamp the torn top skin in place, grind and re-glass the sides. THEN I would scarf the main break in top and bottom skins with very long scarf ratios on top and bottom faces because there is carbon fiber in at least the top and bottom skins right. Carbon needs long scarf ratios (like 50:1) to develop the interlam bonds between the old intact skins and new skins.
For missing bits: I might pre-form some new boat building foam, lay an inside skin on it and then join it to where the old broken bit is. Then use that to create new top and bottom skins.
THEN more foam panels for the missing sides. Lay up new sides, lapping onto the new top and bottom faces.
I will add that among beginners making composite repairs there is a hesistancy to remove enough of the damaged areas. Much simpler to just make a square cut and have a nice square edge for your new repairs to start working from.
Why bother to take all the time to scarf together all the remnants and create a form when you already have the perfect form on the other AMA. You just have to think female form and not male form. At the end of the day which process is going to be quicker time wise ?I would align and locally scarf/laminate the remnants together and essentially create a male mold. Fair and thin down the old laminate to a wafer thin shell then laminate a properly fiber oriented new beam over it expecting nothing from the mold, structurally, just a form.
Because you would be replicating the same questionable method of two halves, stuck together, which put too much emphasis on appearance and cost, less on structural integrity. Better to lose the flanges on the other two beams (like this model did on the ama deck joint) so they match the repaired beams and save yourself the time and materials on a mold nobody needs.Why bother to take all the time to scarf together all the remnants and create a form when you already have the perfect form on the other AMA. You just have to think female form and not male form. At the end of the day which process is going to be quicker time wise ?
When you come to sell the boat and two beams are looking like someones had a go at repairing them badly as compared to having two complete new beams made, I wonder how much that will effect the resale value ?
Holy shit; sorry to read and see this. They are great boats but you really need to stay on top of beam maintenance.
What TRi said. Steve would be my first call. He had beams. Not sure if he still does.Steve Marsh who runs Finish Line, http://finishlineotc.com, in Florida may have “spare parts”. He has picked up some damaged F27’s in the past or Don Wigston, also in Florida, runs Windcraft. https://windcraftmultihulls.com
the New England team you reached out to probably have reached out to them, they all are Corsair dealers.
It is hard to tell from the pictures, but one looks like the Aka seam may have separated.....Ian has/had a bulletin probably moved to here: https://fct.groups.io/g/F-Boats/files which seems to have the old yahoo group archives.
Could you tell if one Aka caved first? Followed by cascading failures?
I would look up the bulletin and check the starboard side per the guide.
Yes, this exactly.I think this picture shows exactly the type of failure described in the PDF file. Starts at the beam seam, hits the bolt hole (stress raiser) then cracks the side and slowly peels the beam. IMO, the top of this picture is where the failure ended. It started at the bottom.
"Should the glue line fail here, and be undetected, the failure will grow along the join flange until it reaches a bolt, which then acts as a stress raiser.
A vertical crack running up the side of the beam may then develop from that bolt.
Now it gets serious and must be repaired without delay"
You may have had this sort of partial failure for a long time and just didn't see it. So this beam probably failed first and then
View attachment 449920
I'm not sure what is meant by this. The boat is of the design before the amas were changed to reduce production cost and difficulty. So, yes it is different than the later design, but it is a Corsair F27 nonetheless.They appear to be a different design than a Corsair 27, interesting.