DRAGONFLY Trimarans User Forum

Of the retracting beam on the 25?

There is the hinge which is bolted onto the fiberglass piece that is riveted onto the hull. Inside there is the mast section across the boat. What is inside the part to which the hinge is bolted? Is it just bolted to the fiberglass? Or is there something that the mast section/hinge etc all bolt to? Metal?

The reason I ask is because there is movement in my forward attachment points. There are a few cracks in the fiberglass and they open when the weight increases, ie when the beam swings out when out of the water.

It appears PO, or PPO addressed this by adding a shroud that goes to the outside of the beam and forward of the mast, which is a good idea, as, frankly i wondered how Quorning let all this weight rest on that hinge. Mine is the only boat I've seen, of all the pictures out there, that has a shroud supporting the forward end of the beam. I mean, sailing hard the windward float is airborne and with people on it, and the tramp there is a lot of weight hanging on that hinge....

So again, what is inside there? Knowing that will help me to proceed.

Your boat was not made by Quorning, it was made by Paul Contouris - PC Mould in Canada. As you can see by the work you corrected he took some "short-cuts" that you have since corrected. I can tell you that those front shrouds came directly from the factory. As for what that hinge attachment point is made from, I couldn't tell you. I would hope it is a piece of aluminum under fiberglass.
You could always drill a small hole and see what comes out.
By the way, there is supposed to be a steel band that runs in a semi-circle fashion between these two attachment points. Tread very carefully in this area, I do know of someone that cut through this band - boat was totaled!
I like what you did with the trailer!
On another note, If the PO didn't break that boat, you never will. There is no one I know that sails as hard as him. I know he has been out in 30+ knots of wind with that boat. This being your first tri, you are naturally going to be a little apprenhensive until you learn what the limitations are of your boat.
Keep up the good work.
Ted

Oscar wrote:snip
I mean, sailing hard the windward float is airborne and with people on it, and the tramp there is a lot of weight hanging on that hinge....

snip.

Don't forget that the windward shroud is also holding it up.

Thanks Ted.....

I'm having trouble visualizing the steel band, but I'll tread lightly. As you can see in the video the forward beam hangs a little lower than the aft. The shroud should help there.

Roger the 30 knots.....I've been known to exceed that I managed to squeeze over 200nm in 24 hours (JAX to FLL) out of my Catalina 42, it took sustained in the high thirties and peaks in the mid 40's to do that......

OK, so PC put the extra shroud on. Good, I actually think that's a good idea. I also noticed from all the pics of Danish boats that the running back connects to the inside and the outside of the float. As it is now, everything is connected to the outside which puts a twisting moment on the big bolts, as evidenced by a slight bend in some of them. I plan on bringing the aft end of the aft shroud inboard. Yes, I know that it will be in the way of the retracting beam, but I'm leaving the outside chainplate for the blocks that are on there, and will equip the shroud with a nice stout snap shackle to flip it to the outside for retracting. On the newer boats the float is lengthened a foot behind the aft pivot, and there the inside end of the shroud is out of the way of the retracting beam, I don't have that luxury.

Speaking of stout, all the chainplates are off right now, and I have put a nice piece of 1708 on the inside where they go, almost a foot down. There were quite a few stress cracks around the three holes that they attach through. There will also be an aluminum plate on the inside to better back the bolts. Also, I'm upgrading the U bolts to the next standard thickness...Much better load distribution.

The pivot bases were off the floats and are being re-attached with thickened epoxy. The old thickened polyester from the factory was brittle and they were loose in some areas and popped right off....not anymore. Also, the three bolts that go through the hull to deck joint on each side of the pivot bases now also go through an aluminum backing plate about a foot long, instead of the little (bent) washers.

I've put a layer of 1708 over the entire deck, and have put solid aircraft rivets through the hull to deck joint every 6 inches or so. It had come loose in some places, and short of taking the whole deck off I couldn't really glue it back properly.

I found a nice white rubber U-channel which I will bed down over the hull to deck joint to make sure no more water gets in there.

The big round hatch is being replaced by a 12x17 hinged hatch for improved access.

I'm pretty happy with how the floats are shaping up. They are now stronger than ever, and have actually lost weight (water) in the process. They're just under 250 lbs each, including beams.