Greetings all...
I have been doing a lot of research on a Stationary High Velocity Test Tank. I have found a pump to move just over 400 gallons of water per minute. The tank I want to build is 8 feet long and 20 inches wide. The ends will be rounded to remove the square corners. The speed will be measured by a actual boat speedometer (Baja makes a speedometer that will measure up to 100 MPH......I know that the measurement wont be dead-on, but for comparisons, it should do the job). My thought is to move the water at a measured speed, say 40 MPH, then with the boat attached to a set of offset fishing line lanyards (this will also let the boat change attitude on its own without any secondary influences on how the boat sits). The boat will be on plane, with the motor idle. As the motor speed increases, the lines will still be tight, because the water is moving past the boat faster than the motor is pushing it . At full throttle, As the boat attempts to move forward and comes to the same speed as the water moving past it, (in this case 40 MPH) the lines will just begin to sag. Then that is the maximum speed. If the lines do not get slack at full throttle, than the water is moving to fast, or if the lines slack before full throttle, the water is moving too slow and needs to sped up in order to give the boat full throttle and measure the actual top speed. This setup also seems to lend itself to measuring attitude and prop wash. ( I didn’t mention this before, but in the sides, I will router out an opening and put plexi-glass at the water line to make it possible to view the attitude of the boat and the prop wash up close. I understand that boat stuff is not rocket science, but I have come a long way so far and I need a way to be able to see the affects different props have on the boat. The props JD tested this spring were running at about 30 - 33 MPH, the ones I am doing now, have clocked at 51.( the test boat is a prototype TS2, I do not know how different the production version is but when money permits I will try one of those) I have several more ideas to try and with winter upon me I guess I HAVE to move into the garage. Once I hammer out the best props to use under controlled conditions, then those props can be run and clocked properly to get the real-world speed
I do not know if anyone has done anything like this before but I MUST do it. My wife has a new job at UPS in the evening and the weekends are filled with family time, yard stuff, errands, and soon enough...cold and rather stiff water in Ohio will end it all for the winter. I haven’t run a test on my props in over a month............ Not to mention that I found it nearly impossible to get decent water conditions for any length of time, in order to compare minor differences. I feel it would be very convenient to roll the tank out side, fire up the water pump and see what happens. No car rides, no hauling box after box of stuff to the dock.
so, any helpful thoughts or outright insults? If you think I am headed in the (generally) right direction, All I need to do is cut some sticks and glue em' . If you don’t , PLEASE let it fly.... Before I drop $1200 on the pump alone, I thought I would bring my idea to most knowledgeable boaters on the net.
Thanks for reading this novel; I hope to see your input.
Steve Deryck SPD-PROPS
I have been doing a lot of research on a Stationary High Velocity Test Tank. I have found a pump to move just over 400 gallons of water per minute. The tank I want to build is 8 feet long and 20 inches wide. The ends will be rounded to remove the square corners. The speed will be measured by a actual boat speedometer (Baja makes a speedometer that will measure up to 100 MPH......I know that the measurement wont be dead-on, but for comparisons, it should do the job). My thought is to move the water at a measured speed, say 40 MPH, then with the boat attached to a set of offset fishing line lanyards (this will also let the boat change attitude on its own without any secondary influences on how the boat sits). The boat will be on plane, with the motor idle. As the motor speed increases, the lines will still be tight, because the water is moving past the boat faster than the motor is pushing it . At full throttle, As the boat attempts to move forward and comes to the same speed as the water moving past it, (in this case 40 MPH) the lines will just begin to sag. Then that is the maximum speed. If the lines do not get slack at full throttle, than the water is moving to fast, or if the lines slack before full throttle, the water is moving too slow and needs to sped up in order to give the boat full throttle and measure the actual top speed. This setup also seems to lend itself to measuring attitude and prop wash. ( I didn’t mention this before, but in the sides, I will router out an opening and put plexi-glass at the water line to make it possible to view the attitude of the boat and the prop wash up close. I understand that boat stuff is not rocket science, but I have come a long way so far and I need a way to be able to see the affects different props have on the boat. The props JD tested this spring were running at about 30 - 33 MPH, the ones I am doing now, have clocked at 51.( the test boat is a prototype TS2, I do not know how different the production version is but when money permits I will try one of those) I have several more ideas to try and with winter upon me I guess I HAVE to move into the garage. Once I hammer out the best props to use under controlled conditions, then those props can be run and clocked properly to get the real-world speed
I do not know if anyone has done anything like this before but I MUST do it. My wife has a new job at UPS in the evening and the weekends are filled with family time, yard stuff, errands, and soon enough...cold and rather stiff water in Ohio will end it all for the winter. I haven’t run a test on my props in over a month............ Not to mention that I found it nearly impossible to get decent water conditions for any length of time, in order to compare minor differences. I feel it would be very convenient to roll the tank out side, fire up the water pump and see what happens. No car rides, no hauling box after box of stuff to the dock.
so, any helpful thoughts or outright insults? If you think I am headed in the (generally) right direction, All I need to do is cut some sticks and glue em' . If you don’t , PLEASE let it fly.... Before I drop $1200 on the pump alone, I thought I would bring my idea to most knowledgeable boaters on the net.
Thanks for reading this novel; I hope to see your input.
Steve Deryck SPD-PROPS
