The pool test was a success - until the chain snapped.
After the half marathon, I sat at my desk and stressed about where our predicted water line was on WiTHiN and how it was going to totally flood the boat through the drive leg. I had visions of it spaying violently up through the gaps in the foam plug and drive leg. Horror in the YWCA pool. The boat sinks and they have to drain the whole pool to get my boat out. Then they hand me a $10,000 invoice for the mess.
I even spent an hour on Skype with Rick calculating the exact location of the water level. It should be about 15 mm ABOVE the top of the wall of the drive leg bay. No doubt about it. If my plug and drive leg itself aren't water tight, water should just flow up through those openings. Why didn't I make the wall higher? I forget - There was a legitimate reason, but I forgot what it was. Rick reminds me that during the design phase, I lowered the drive leg bay walls a bit to allow the drive leg to rotate up through the hole cut in the hull. I had added a lip to the drive leg bay wall, but it was flexible rubber at the hinge to get around it - I wasn't at all confident that it would hold back the flood.
Ben and Stefan came over and we discussed the issue. Someone had the brilliant idea of simply duct taping the bottom of the hull around the drive leg and plug. This way we would be able to conduct all the tests required and be guaranteed that we won't sink. The after that, pull the tape off and test out the drive leg wall.
So that's what we did. We taped up everything using Gorilla Tape (amazing stuff - really) and the inside of WiTHiN was dry. We had three 25 meter lanes at the downtown YWCA, so I was only able to just get WiTHiN moving forward before I had to slam on the breaks by pedalling backward. It was very responsive turning and it was surprisingly stable. It never felt like it was going to tip - even on the sharpest turn.
I stood up and rocked it, still no tipping. I jumped out into the pool and climbed back in from deep water - very stable, no problem. I does not look like outriggers will be required. I think that I have kept the weight low in the hull, and I think that the Hyak sea kayak hull is a fairly stable shape.
Then we rigged up some nylon rope to the rudder then around a pulley attached to the diving board rail down to a 25 pound weight. This is to test the drive leg and prop - if everything is working properly, I should be able to lift the 25 pound weight with about 300 watts of power. As I started to crank on it, the chain broke. That was one thing that I had forgot to do - replace my work chain with a good chain. I had broken apart that old chain about two dozen times and it was only meant as a very temporary chain. No wonder it broke. Oh well.
We pulled the Gorilla Tape off the bottom and - no water. I bounced around a bunch in WiTHiN and still dry as a bone. Then we pulled the drive leg bay plug out and noted that the water line was about 1/2" BELOW the top of the bay wall. That was a pleasant surprise. Then I rotated the drive leg out and still no overflow. The water level at the drive leg slot was much closer to the top of the wall, but my rubber lip was doing it's job and keeping any water from splashing over into the boat. This was GREAT news! I think the reason the water line was slightly lower in the bow where the drive leg is located is probably because of weight distribution causing a slight bow-up geometry.
All in all, a successful day. A PR at the half marathon in the morning, then a successful pool test that night.
Next - open water to see if WiTHiN is as fast as it is supposed to be. This is a critical test. If for some unknown reason, WiTHiN isn't close to it's 10 km/hr predicted speed at 150 watts of power, then breaking the current record of 168 km is going to be difficult.
I would like to get WiTHiN into Glenmore reservoir this weekend if possible. The ice just melted and it's all open now. I need to find some support - someone in a boat to help film and to be there for safety in case I go for a swim. That water is only about 2 degrees C.
After the half marathon, I sat at my desk and stressed about where our predicted water line was on WiTHiN and how it was going to totally flood the boat through the drive leg. I had visions of it spaying violently up through the gaps in the foam plug and drive leg. Horror in the YWCA pool. The boat sinks and they have to drain the whole pool to get my boat out. Then they hand me a $10,000 invoice for the mess.
I even spent an hour on Skype with Rick calculating the exact location of the water level. It should be about 15 mm ABOVE the top of the wall of the drive leg bay. No doubt about it. If my plug and drive leg itself aren't water tight, water should just flow up through those openings. Why didn't I make the wall higher? I forget - There was a legitimate reason, but I forgot what it was. Rick reminds me that during the design phase, I lowered the drive leg bay walls a bit to allow the drive leg to rotate up through the hole cut in the hull. I had added a lip to the drive leg bay wall, but it was flexible rubber at the hinge to get around it - I wasn't at all confident that it would hold back the flood.
Ben and Stefan came over and we discussed the issue. Someone had the brilliant idea of simply duct taping the bottom of the hull around the drive leg and plug. This way we would be able to conduct all the tests required and be guaranteed that we won't sink. The after that, pull the tape off and test out the drive leg wall.
So that's what we did. We taped up everything using Gorilla Tape (amazing stuff - really) and the inside of WiTHiN was dry. We had three 25 meter lanes at the downtown YWCA, so I was only able to just get WiTHiN moving forward before I had to slam on the breaks by pedalling backward. It was very responsive turning and it was surprisingly stable. It never felt like it was going to tip - even on the sharpest turn.
I stood up and rocked it, still no tipping. I jumped out into the pool and climbed back in from deep water - very stable, no problem. I does not look like outriggers will be required. I think that I have kept the weight low in the hull, and I think that the Hyak sea kayak hull is a fairly stable shape.
Then we rigged up some nylon rope to the rudder then around a pulley attached to the diving board rail down to a 25 pound weight. This is to test the drive leg and prop - if everything is working properly, I should be able to lift the 25 pound weight with about 300 watts of power. As I started to crank on it, the chain broke. That was one thing that I had forgot to do - replace my work chain with a good chain. I had broken apart that old chain about two dozen times and it was only meant as a very temporary chain. No wonder it broke. Oh well.
We pulled the Gorilla Tape off the bottom and - no water. I bounced around a bunch in WiTHiN and still dry as a bone. Then we pulled the drive leg bay plug out and noted that the water line was about 1/2" BELOW the top of the bay wall. That was a pleasant surprise. Then I rotated the drive leg out and still no overflow. The water level at the drive leg slot was much closer to the top of the wall, but my rubber lip was doing it's job and keeping any water from splashing over into the boat. This was GREAT news! I think the reason the water line was slightly lower in the bow where the drive leg is located is probably because of weight distribution causing a slight bow-up geometry.
All in all, a successful day. A PR at the half marathon in the morning, then a successful pool test that night.
Next - open water to see if WiTHiN is as fast as it is supposed to be. This is a critical test. If for some unknown reason, WiTHiN isn't close to it's 10 km/hr predicted speed at 150 watts of power, then breaking the current record of 168 km is going to be difficult.
I would like to get WiTHiN into Glenmore reservoir this weekend if possible. The ice just melted and it's all open now. I need to find some support - someone in a boat to help film and to be there for safety in case I go for a swim. That water is only about 2 degrees C.
Labels: boatbuilding, expedition
