painted gearcases vs. "naked" g.c.
 

does anybody have any speed
increase figures, {if any} on
bravo gearcases that are non
painted vs. painted gearcases,
II & III SSM'S that run "deep"
have no paint, so i figure theres
something to gain.
just curios.
jt

PAINTED VS POLISHED
 

J.T. NO SPEED FIGURES /BUT AS YOU KNOW THE SMOOTHER IT IS CREATES LESS FRICTION OR DRAG WHICH RESULTS IN INCREASED SPEED,HAVE THE CSES POLISHED IT'S WORTH IT PLUS IT LOOKS GREAT,

OH CON TRARE ! THE MORE POLIHED THE MORE SURFACE TENISION OR STICK IT HAS !!!!!!!! (SLOWER )

THIS IS WHY SPEED COAT IS A FINELY COURSE MATERIAL LIKE GRAPHITE ,TO BREAK THE SURFACE TENSION :p :D :D :D

Bobby, I have heard exactly what you have said.

I met a guy at a poker run that had polished lowers, said there is 1 pro: looks good
and
3 cons: lost 3mph and
spent quite a good bit of money to do it and
it took so much work to keep it up, he stopped doing it

This was on a #6 that didnt have paint and then he polished it, i couldnt tell you about with paint, but you are right, all the high-pro drives have no paint but arent polished, so i guess that would be the "fastest" drive.

yes, your correct but how much?just like a prop one with a satin finish will run faster than a polished prop because of friction , but in my opinion the difference in apperance the speed loss of (guessing).05 mph or( less) is not worth it.Especially on a stainless prop as they rust due to the high carbon content. also i have never seen a gear case that has been re-painted where they paint does not peel off in diffrent areas. (JUST MY OPIOION))

YEP PROPS ARE A DIFFERENT ANIMAL THAN DRIVE AND BOAT BOTTOMS ,BUT I THOUGHT IT WAS THE NICKEL IN THE PROP THAT MADE IT RUST I DID NOT THINK CARBON RUSTED ,BUT I DON;T KNOW PROPS JUST THE DRIVES AND BOAT BOTTOM

depends not on the carbon content but on the content of ferrite (iron) that exists in all ferrous metals (hence the name). Ferritic stainless steel having the most as opposed to austenitic stainless steel. The addition of reletively large amounts of chomium and nickle is what give ss it's corrosion resistant properties but also contribute to whats called the "carbon equivalent" - a ratio of an alloying elements contribution to the hardness or brittleness of the material as compared to if those elements were pure carbon.

Umm, it's been about 16 years since my last metallurgy class so please, don't quote me on this.

Okay, I appreciate the high-tech explanations, but let's make it plain and elementary for dudes like me......

In reference to PROPS ONLY (not gear cases and boat bottoms): are POLISHED stainless steel props FASTER or are they SLOWER???

Thanks guys :)

HEY KAMMA
EVERYTHING I'VE TRIED HAS SAID SATIN PROPS AS HUSTON PROPS SAYS ABOVE ARE FASTER ,LIKE THE DRIVE AND BOAT BOTTOM ALTHOUGH IN THE CASE OF THE PROP I DON'T TRULY UNDERSTAND WHY ? THE HULL AND DRIVE I EXPLAINED ABOVE AND THATS RIGHT I JUST CAN'T EXPLAIN THE PROP SPEED

WILL GET BACK WITH YOU ON YOUR MOTOR ,GOT TO DYNO ONE NOW 1:19 EST :D :D :D

Yeah...The polished lowers do look nice but mine are showing stains from the hardness of our Lake water.
I'll just hit them with a fine ScotchBrite pad every now and then...polishing sucks!
So is that satin props run faster or polished?
Sorry im a bit slow.:p

THE PROPS ON MY FOUNTAIN THAT I DREAM ABOUT HAS POLISHED PROPS ON IT. (PERSONALLY I DONT THINK YOU WOULD SEE THE DIFFERENCE OTHER THAN APPERANCE.

I AGREE IT WILL HELP SOME FOR THE PROP TO BE NOT POLISHED
BUT ONLY 1 MPH ON A LIGHT BOAT

:D

J.T. WHAT'S UP ???????/If your case's are now painted they probably, have paint pealing or wearing off ?have the cases bead blasted with a very (very fine) sand. To up keep use a 3-m brown scotch-brite pad,run the boat do the speed test,then when the snow quits flying in IOWA ha get down and dirty and polish the cases with air and buffing tools /you know how / and then give us the results.ha/see ya!!!!!!!!!!

DARIN,
i f%*ked up L/H skeg over at the mississippi
this year, had the machine shop i deal
with weld it back up, i refinished it, using
self etching primer etc., paint still is peeling,
think i will strip down both drives,
rough up the surfaces, and try them next spring,
i have low water pickup lower's,
i may try std. side pickup lowers, off a friends boat,
i heard somewere that side p/u lowers were
worth up to 2 mph over low water p/u at over 80 mph,
anybody else heard this too ??????
talk 2 u l8er
j.t.

labbed/with blasted trailing edge
 

Mike yes after labbing aprop we can tape off the entire blade excluding the trailing edge and bead blast the cup it has a neat apperance and we can also go all the way around the entire edge of the blade about 1/8 " but is very time consuming .

get fancy/powder coat gear case?
 

have you seen or heard of this being done ?iam sure it would be $$$$$$$$$$ unless you know the right person? just curious/asta la pasta/ Darin:rolleyes:

Prop Talkin'
 

All this talk has got me wondering....

1) Of course go fast boats use stainless props, 'cause it's much stronger than aluminum. However, what number stainless do you typically use? Electolysis isn't an issue 'cause we don't keep our boats in the water long enough to be a problem (I hope), but which stainless is strongest?

2) When using polished stainless in salt water I've noticed the whitish residue that accumulates on the props. How do you clean and would a coated prop still get this residue? I'm assuming it's high speed (i.e. heated salt) mixed with cavitation (sp?).

How about putting POR 15 on props???? Ha ha just kidding!

Any good reading material on these subjects?

Thanks and I'm just thinkin out loud :D :)

Sorry. My spelling sucks tonight!