Is there such a thing as building a boat that is to light? Is there any truth to the school of thought that a boat that is too light is prone to blowing off the water? It would be interesting to see the hull design, race ready weight and powerplant data of heat racing and speed record holder IMPBA scantiond event winners. Some of my friends accuse me of thinking about this to deeply but I can't help it; this is fun stuff!

Raymond

I remember a old forum on the weight stuff when i first created my account 06 a member said something like for every gram or oz you loose 3.849176231 mph ,how he calculated that I have no ideal. maybe 4.69012 mph for every gram . any ideal's

Advanced Builder,

That is a lot of loss per gram! Even it is was an oz measure that would still be allot. How can you remember the big long decimal number? I suffer from CRS (canā€™t remember stuff) It would not be hard to prove or disprove. If one of the members with a speed logging GPS would make a timed run then follow that run with a few succeeding runs with known weight increases and logging the data for posting. That would be an interesting experiment. Anyone up for it? If no one is, I will someday when I get a speed logging GPS unit.

Raymond

This is one that could be argued/discussed forever. Some of the SAW record holding boats were actually on the heavy side so that kind of shows that it can be more about setup than dropping weight.
I rember reading about Glenn Quarles and his quest to blow the IMPBA "A" hydro record out of the proverbial water. He dropped every gram that he could and stayed awake nights thinking of ways to make his hydro lighter. He went as far as remonving the mounting tabs off the servos, drilling holes in the cases and not running a strut, only a brass tube as he knew where he needed it to be. The boat barely floated as there wasn't much of a hull or sponsons to keep it above water if it stalled or flipped.
Weight certainly can help in rough racing water conditions. It helps also if you want a boat that is good for more than one run.

Hi Ron,

I agree, there is a practical limit to any lightening effort butā€¦. my notion is more of a knowledge sense of what the affects are so that best practice building techniques can be employed to build a reliable and competitive boat . Ok, letā€™s say we had two boats with identical equipment set-ups with one being of ā€˜standard heat racing weightā€™ and the other lighter. How light would the lightest boat have to be before it was unstable at racing speed or how light could we get it before it became unstable at speed? This is all theoretical thinking here soā€¦. If we could make it as light as we wanted in dream land could we pass up a weight that would cause us to have control issues? I think you suggested the answer to this question to be yes when you referenced rough water conditions.

Yea, yea, I know, I am thinking to much here butā€¦I canā€™t really help it. I am really having a ball with this hobby and want to learn all I can.

Something I would like to see done is to take a boat, any boat with known speed performance numbers and weigh it and measure the balance point and then to alter the weight and balance in a controlled and systematic manner while not making any other performance adjustments and then running the boat again to re-measure the speed data in support of making determinations of what the affect of those changes are. (wow, that was a long sentenceļŠ)

Yea, yea, I guess I should be doing this already with my boat in an effort to ā€˜tuneā€™ it but I have not been in the RC boating hobby long enough to get there yet. As soon as I get myself a GPS speed measuring devise I will embark upon that testing journey and report my results. Until then is there anyone with the proper equipment that could or has done this type of testing?