Scuffing hull another proposing ?

[SweetZ28]

well after seeing all the fuss about wether scuffing the boats bottom will make you go faster some guy's swear on it but yet i do not get this if it works then why do guy's?

polish there props wondn't if you wet sand them fully dull a layer of water will stick to the props surfaces( like on the hulls bottom when scuffed) thus making the prop spin faster because it will cut through the water easy because water on water is slipereir than a shiny surface is? if it works on the hull it should do the same on the prop...so why does everyone polish the props.... why not polish your hulls bottoms then?

[Rumdog]

This has been discussed quite a bit actually. "Everyone" don't polish them. I never have. The only way to test the theory is to run the exact ame rig on the exact same prop, one polished, one non. I can't see how it would matter either when it is tearing through the water at 30,000 rpm. I think it's just more of a preferance in look. Sharp and balanced is the key.

[Flying Scotsman]

I am just lazy and wet sand them with 600 grit. I do like the look of a buffed prop though and it is virtually impossible to prove whether one method is better than the other.

Douggie

[Rumdog]

Yeah, me likes shiny things too.

[Jeepers]

Jay Turner has said a few times that a satin finished prop is faster than a polished prop? maybe he will chime in and give a good explanation. me I just finish with 400 when I feel like it, mostly because my props take a beating there is always some piece of wood, or turtle that I end up hitting

[Jeff Wohlt]

Tom at Octura will tell you the same...leave the matte finish on it. S&B and run it.

[SweetZ28]

I say if matt finish works on boat hulls it should be the same on a prop same thing is happening you want it sto slip and cut through the water as easy as possible..... I say matt finish is the way to go!

[m4a1usr]

Say what you want but we can all take a lesson from REAL boats. Not the RC kind. All of the high performance boats from monos, hydros and Cats that are in the winners circle run polished props. At least those who run wide open and not in a closed circuit race. There is a slight performance increase in a polished prop over one that is not smooth finished. Need proof? Try reading about prop performance from the makers of real props. There's a herd of them out there. Go to the pits of the unlimited hydros. You wont find one prop that does not shine like a mirror

And then theres sources like, http://www.rcprops.com/TechNotes/rcprop_tech_info.htm

John

[Karfrik]

Less friction= more speed.But i do also question this for the hulls.Back in the day i used to polish my real boat hulls including sailboats.Now i scuffed my rcboat hulls....................lol....i just go with the flow!!!.......,Albert

[SweetZ28]

maybe with a prop they make it shiny so it grabs the water harder so it launches the boat more efficently?

[Rumdog]

Say what you want but we can all take a lesson from REAL boats. Not the RC kind. All of the high performance boats from monos, hydros and Cats that are in the winners circle run polished props. At least those who run wide open and not in a closed circuit race. There is a slight performance increase in a polished prop over one that is not smooth finished. Need proof? Try reading about prop performance from the makers of real props. There's a herd of them out there. Go to the pits of the unlimited hydros. You wont find one prop that does not shine like a mirror

And then theres sources like, http://www.rcprops.com/TechNotes/rcprop_tech_info.htm

John

Water doesnt scale. It isn't the same on a r/c boat prop vs a prop 1 ft. plus in diameter.

[MarkF]

Polished props have a little more bite out of the hole. Which is good when you spin out in a race and need to get the hull on step quicker. Iv'e always polished my saw props because some of the props we use cavitate alot. Iv'e tryed my props with the satin finish before I polish them but I didn't notice any difference in speed.

Mark

[m4a1usr]

Water doesnt scale. It isn't the same on a r/c boat prop vs a prop 1 ft. plus in diameter.

Quite the contrary. Fluid friction does not have scale issues in calculations. Its a constant for an item whether its 1" in dia or 10 feet in diameter. Fluid dynamics are calculated in the amount of force due to viscosity, surface finish or texture and shape of the object. If you take scaled props of exact design and proportion but of different sizes the friction coefficient will be exactly the same. Thats why its a constant providing they are operating in the same media.

John