Joe ran your specs through my speed and prop calculator and came up with changing to a SS prop will give you a top speed of 36.4 mph as you tested. I recommend PTprops as they have a return program for $80 if the 1st is not quite right. Okay the program throughout the 36.4 mph at your weight of 1940lbs and a SS prop the SRD 11.25 x 16 SRD from PTProps https://www.ptprop.com/c-class-propellers1.html If you are constantly loading to 2400lbs then you want an 11.25 x 15 pitch. Be aware the rang of speed could be plus or minus a couple of miles per hour as the model throws out.
The SRD has some rake so it will hold onto the water longer making steering easier.
Please ask if you need any help or questions.
Tom
FS 17 - Raised Sheer
Re: FS 17 - Raised Sheer
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
Re: FS 17 - Raised Sheer
Thanks Tom. I'll give something like that a try in the spring. If I still have problems with ventilation are there any specific props you would recommend? Some people seem to suggest 4 blade props can help with that, or perhaps just a 3 blade with more aggressive cup or something like that.TomW1 wrote: ↑Sun Jan 23, 2022 1:34 pm Joe ran your specs through my speed and prop calculator and came up with changing to a SS prop will give you a top speed of 36.4 mph as you tested. I recommend PTprops as they have a return program for $80 if the 1st is not quite right. Okay the program throughout the 36.4 mph at your weight of 1940lbs and a SS prop the SRD 11.25 x 16 SRD from PTProps https://www.ptprop.com/c-class-propellers1.html If you are constantly loading to 2400lbs then you want an 11.25 x 15 pitch. Be aware the rang of speed could be plus or minus a couple of miles per hour as the model throws out.
The SRD has some rake so it will hold onto the water longer making steering easier.
Please ask if you need any help or questions.
Tom
Re: FS 17 - Raised Sheer
Joe the two props I gave you above have added rake that hold water on the blades longer and will do the same as added cup. Usually, cup and rake work together and you go down a pitch for that. I will look and see what I come up with.
Tom
Tom
Restored Mirror Dinghy, Bought OD18 built by CL, Westlawn School of Yacht Design courses. LT US Navy 1970-1978
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