Custom mast prototype-stress test

Since we first started selling kits for the PT 11 we have been continually updating the kit, building process, and the boat to make it better.  It's in our nature to do this and it means the boats get stronger, lighter, easier to build, perform better, etc.

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click the photo for a detailed post about our rigs.

A good while back, through friends in the high tech world, we developed a connection with a company called Innovative Composite Engineering, a renown carbon tube company in Washington state. They now make our lightweight booms for the sailing rigs.

The 7 1/2' booms are incredibly lightweight. The tubes start at 20 ounces each. With the gooseneck, hardware, main sheet & vang tackle, they weigh 40 ounces.  No one is likely to get knocked out by one of these booms in a gybe and so far they have been strong enough (remember not to over-do the boom vang).

While the masts we sell have been extremely reliable, we knew they could be lighter. After a year of bugging I.C.E. to come up with a mast for us, we finally got a prototype.

The masts that we have been using are modified windsurfing masts. We have to modify them because they are stepped in a short socket and the loads where the mast comes out of the socket are quite significant and different than the loads applied to a windsurfer mast.
The new masts have extra layers of carbon at the lower end starting just above deck level and ending just above where the boom connects to the mast. These extra layers of laminate mean that we will have to do less work to the lower end to make them strong enough.

How light is the new mast? It’s light! The current two-piece masts weigh 104 ounces (2937 grams); already impressively light. The new mast weighs 69 ounces (1950 grams)!

We stress tested the prototype mast as shown on land (and on the water) using two 180 pound people on the rail and the mast was fine.
Having two people on the rail is strongly discouraged by us because of the twisting loads it puts on the boat, the very high loads at the mast step, and finally the mast.
In other words, what we are really after is a feather weight mast, not a mast that could break the boat.

The weight of the rig is directly related to ease of use. Our theory (and it seems well proven now) is that the easier the sailing rig is to use, the more it will be used. Our rig was already the lightest, easiest to use, and most power-per-pound dinghy sailing rig out there. Now it is significantly lighter.

We will pay quite a bit more for the custom masts, but because they will be less work to finish we will likely be able to keep the complete sailing rig cost the same.

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Ashlyn can't get much mast bend.
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Russell and James hike out with approx 360 Lbs.

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We did a load test on the ground, tying the mast to a building and getting two people hiking out on the rail. This was a little scary, but a very effective way to see if the mast was strong enough. (RB)

Ashlyn's footnote: Our ballast assistant in these photos is a local luthier. Here he is holding the 15' 1" mast up by the tip to see how it sounds as a Didjeridoo.

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What sound can it make?

See this silly video to hear....

I had him lower the tip for the video because, in the camera, the green house behind appeared to dominate. I regret this now since it would have looked fine. It was impressive how easy it was to keep it up in the air. (AEB.)