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MOTORS
I have the motors ready to go in the boat. On the first Vortex, I noticed an extremely loud whine coming from the boat at full throttle. I figured it was drive line related, with the usual suspects, bad shaft alignment, bad grease, stuffing tube kinked when bending in the radius, bad or loose motor/shaft coupler. None of these were a problem... I even sanded down my flex shaft thinking the wind on it was rubbing on the stuffing tube, no go. I actually went too far on that, and had to replace it!
What I found made sense once I found it, isn’t that always the case. The Vortex is a great hull, so much room to put parts just where you need them. But it IS a hollow shell, with not one cross frame in it. As such, it can resonate like the body on an acoustic guitar. I noticed on fine examination that the epoxy glueing the stuffing tube to the hull had little tiny stress fractures in it. I’ve seen this type of structural failure before. I’ve done quite a few FEM analysis on failed structures, usually motor related. Resonance vibration can be a real show stopper. So I glued an aluminum plate in the bottom of the boat using slow curing marine epoxy. The plate acts as a dampener to the resonance buildup. Worked like a charm, no more noise! So I decided to forgo that trip down the rabbit hole and incorporate a motor mounting plate into the dual design. This plate eventually gets glued in, so all angles have to be double and triple checked.
I fabricated the motor mount rails, attached the the motor plate with 3, #2 flathead screws per rail. I used 2mm socket head screws to mount the rails the the motor mounts I bought on OSE. It’s a very solid affair. Those are 5mm to 0.150” OSE couplers with thrust bearings on each motor. I got my X442 matched prop pairs from Chris (dasboata) and they look great! I’ve been keeping a tally sheet on the gram weight of the components going into the build. I’m actually on track for about 10lbs, very happy with that! Still waiting for ESC’s to arrive... It’s getting pretty close!
I have the motors ready to go in the boat. On the first Vortex, I noticed an extremely loud whine coming from the boat at full throttle. I figured it was drive line related, with the usual suspects, bad shaft alignment, bad grease, stuffing tube kinked when bending in the radius, bad or loose motor/shaft coupler. None of these were a problem... I even sanded down my flex shaft thinking the wind on it was rubbing on the stuffing tube, no go. I actually went too far on that, and had to replace it!
What I found made sense once I found it, isn’t that always the case. The Vortex is a great hull, so much room to put parts just where you need them. But it IS a hollow shell, with not one cross frame in it. As such, it can resonate like the body on an acoustic guitar. I noticed on fine examination that the epoxy glueing the stuffing tube to the hull had little tiny stress fractures in it. I’ve seen this type of structural failure before. I’ve done quite a few FEM analysis on failed structures, usually motor related. Resonance vibration can be a real show stopper. So I glued an aluminum plate in the bottom of the boat using slow curing marine epoxy. The plate acts as a dampener to the resonance buildup. Worked like a charm, no more noise! So I decided to forgo that trip down the rabbit hole and incorporate a motor mounting plate into the dual design. This plate eventually gets glued in, so all angles have to be double and triple checked.
I fabricated the motor mount rails, attached the the motor plate with 3, #2 flathead screws per rail. I used 2mm socket head screws to mount the rails the the motor mounts I bought on OSE. It’s a very solid affair. Those are 5mm to 0.150” OSE couplers with thrust bearings on each motor. I got my X442 matched prop pairs from Chris (dasboata) and they look great! I’ve been keeping a tally sheet on the gram weight of the components going into the build. I’m actually on track for about 10lbs, very happy with that! Still waiting for ESC’s to arrive... It’s getting pretty close!
The thing I like the least.. I wish I had a good compressor and air gun, but I have to struggle with cans... To heavy flow, orange peel, runs and flat not taking the paint. I’m going to run mine without paint at first, then maybe I’ll get fired up to get through that! I do want to paint this dual hydro the paint scheme of the ‘85 Executone, it was my brother’s first ride... The first Vortex is done up like his GP-55 boat, it’s my avatar...
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