Lance Rowe visits M.R. Props to get a detailed look at what goes into the repair of a boat propeller. Part 1 of a 2 part series produced for WBSBN.com by AVIO Productions
Nice work. Six years on I hope this guy is still around and enjoying working metal, or at least has found a comfy chair near good friends. :-)A minor quibble: the description he gives for cavitation is actually "ventilation" - the prop sucking air down from the surface (so yeah, the "cavitation plate" on an outboard is there to reduce ventilation).Cavitation can occur on any propeller and is caused when the forward side of the blade (called the "back" because you're usually looking at it from behind the boat) pulls so hard on the water that the pressure drop vaporizes the water into bubbles (which can erode the metal of the blade when they collapse) or sheets (usually not as damaging).Also, in larger propellers the convex curve over the back of the blade does most of the work of pulling the boat forward. Blades have a foil shaped into their thickness (they're spinning wings, really), so grinding the back flat can reduce the amount of thrust generated by that part of the blade just like a small reduction in pitch would, and this too can produce vibration.Cupping the trailing edge of the blade is much like extending the flaps on an airplane wing: it increases the effective camber of the blade's foil shape and allows it to produce more thrust for a given overall pitch angle. Cupping does disturb the flow over the blade when going in reverse, often with a noticable loss of thrust.
It's a tough business, because it's a skill and it should be very valuable, but unless it's very special prop you are so limited to how much time you can put into it.
I used to recondition my props, but it cost more to recondition one then to buy one. I can recondition for $75 or buy new for $50. You are absolutely correct though... a lost skill. I boat in the east coast intercoastal waterways and constantly chew through props. At least one a season. Always aluminum and I keep a spare stainless steel prop stashed onboard.
I'm not sure if the guys in this video are misogynists themselves, or if they're making fun of men who can't own up to their own mistakes and instead are cowards and blame it on their wives/girlfriends...
Christine Bradstreet actually he didn't blame all the dings on woman, he was saying all the "too proud to admit it men" blamed it on the woman. He was being witty and actually putting the blame back on the men who did it. It's a good video, you should watch it...
It's over-reaction like yours that give the female gender bad representation. You comment like you are taking a stand for women but you are only perpetuating stereotype.
I truly admire people that know their trade!!!
This guy is Master of Propeller
Nice work. Six years on I hope this guy is still around and enjoying working metal, or at least has found a comfy chair near good friends. :-)A minor quibble: the description he gives for cavitation is actually "ventilation" - the prop sucking air down from the surface (so yeah, the "cavitation plate" on an outboard is there to reduce ventilation).Cavitation can occur on any propeller and is caused when the forward side of the blade (called the "back" because you're usually looking at it from behind the boat) pulls so hard on the water that the pressure drop vaporizes the water into bubbles (which can erode the metal of the blade when they collapse) or sheets (usually not as damaging).Also, in larger propellers the convex curve over the back of the blade does most of the work of pulling the boat forward. Blades have a foil shaped into their thickness (they're spinning wings, really), so grinding the back flat can reduce the amount of thrust generated by that part of the blade just like a small reduction in pitch would, and this too can produce vibration.Cupping the trailing edge of the blade is much like extending the flaps on an airplane wing: it increases the effective camber of the blade's foil shape and allows it to produce more thrust for a given overall pitch angle. Cupping does disturb the flow over the blade when going in reverse, often with a noticable loss of thrust.
Thanks! Excellent tutorial on prop repairs.
I hope a boat is not trying to break any "Land speed records"
Nice video, thanks!
Infact outboard engine is one of the best because it is easy to understand and know the fault immdiatlly
Very good job
Where is part 2...
That philly accent is something serious
It's a tough business, because it's a skill and it should be very valuable, but unless it's very special prop you are so limited to how much time you can put into it.
wheres part 2 though? i saw start but not finish :( jw
hola amigo le pregunto, los moldes de fundicion para acomodar las palas, como logro hacerlos
for some reason part 2 was uploaded by WBSBN? just you tube search"
Boat Propeller Repair Part 2
W sbn
man nice work
I hv been in repairing outboard for 30yr
I did that kind of work for 16 years. In Settle (Ballard). I could do it. I'd like to work with props again. I'll be Free in 3.5 years or so........
A lot of physics cheer
Good video of probably what will soon be a lost art, in this age of throw away stuff and buy another piece of non repairable junk.
I used to recondition my props, but it cost more to recondition one then to buy one. I can recondition for $75 or buy new for $50. You are absolutely correct though... a lost skill. I boat in the east coast intercoastal waterways and constantly chew through props. At least one a season. Always aluminum and I keep a spare stainless steel prop stashed onboard.
Damn wife.
just get a new one! cheapest part of the boat!
Please show the prop when describing what you’re talking about. Don’t need to watch you talk.
... Use what they call "computers"
Lol
M r props. M r not! O s m r. O s. M r props!
I'm not sure if the guys in this video are misogynists themselves, or if they're making fun of men who can't own up to their own mistakes and instead are cowards and blame it on their wives/girlfriends...
They are making fun of men.
Telling on other men... GOOD MAN CODE ... SPOS.... Probably his own shit. What does it matter who did it?
Several real stupid questions by the interviewer. Duffus.
I turned off your video when you blame all the dings on women.
Christine Bradstreet actually he didn't blame all the dings on woman, he was saying all the "too proud to admit it men" blamed it on the woman. He was being witty and actually putting the blame back on the men who did it. It's a good video, you should watch it...
Jeez... take the joke... Is understanding sarcasm that dead nowadays? It is a ding on the men, not the woman.
Now that is just like a woman, didn't listen, only heard part of what was said, and turned her brain off. Can't blame a man for that !
Christine Bradstreet it's a tongue in cheek poke at the men who blame their wives and or girlfriends. Not a dig at women in general.
It's over-reaction like yours that give the female gender bad representation. You comment like you are taking a stand for women but you are only perpetuating stereotype.