Dings in prop?

[Stoo]

I have developed a few minor "dings" in my s/s prop from occasionally using it as a depth sounder. Do you think they make much difference to the performance of the boat? (Engine is a 150 Yamaha)

Is it reasonable to just grind them out, or should I send the prop into a "pro" for repair...?

[BogMonster]

I'd get it fixed properly. I got a new 19" pitch for my engine and was up to 39kts with much improvement of the cavitation problems. I proceeded to smack it on something (not the bottom, I think I hit something in the water) and chipped the leading edge and I'm beginning to think that's where my missing 3-4kts is and its definitely made a difference to the cavitation when turning, its much worse than it was when the prop was in perfect condition.

If it was practical to get a prop repaired here I would, but I guess it will have to be another new one

Would never have thought relatively minor leading edge damage would make that much difference but it seems to.

[jyasaki]

I'd be a little leery about grinding them out. You'll change the balance more on a SS prop, as the metal is heavier than aluminum. The differences in blade thinckness at the ground sections probably won't do you much good, either.

A prop reconditioning that doesn't require much welding should be less than $100 or so, as I recall. Not too bad when you consider a brand new SS prop will upwards of about $250.

jky

[pathalla]

Stoo, I have never much messed with prop dings/bends or damage... always took it to the prop guy. I recently discovered that if you use a block of wood on one side of the blade and a hammer on the other it is surprising how easy small dings are straightened out. Hold the block tightly against the blade and start out gingerly hammering the bent portion of the prop, watch the results. IF it is aluminum, if stainless, take it in.

[Limey Linda]

Originally Posted by pathalla

Stoo, I have never much messed with prop dings/bends or damage... always took it to the prop guy. I recently discovered that if you use a block of wood on one side of the blade and a hammer on the other it is surprising how easy small dings are straightened out. Hold the block tightly against the blade and start out gingerly hammering the bent portion of the prop, watch the results.

That is a good fix for minor dings. However , I prefer to use a tightly packed sandbag ( or a bag of #7-8 lead shot)with a piece of leather over it. This supports the shape of the blade.
Lots' of small taps with the the ball end of a ball pein hammer and file/sand to finish. Take it slow.

[pathalla]

Originally Posted by Limey Linda

That is a good fix for minor dings. However , I prefer to use a tightly packed sandbag ( or a bag of #7-8 lead shot)with a piece of leather over it. This supports the shape of the blade.
Lots' of small taps with the the ball end of a ball pein hammer and file/sand to finish. Take it slow.

Thanks for that Limey, I will try that the next time I ding a prop, shouldn't be too long...

[Stoo]

Decided to fark the prop... Finally got out on the lake and in for a dive today! Water temp is a baulmy 36 up top and 34 at 100'... Just like Little Cayman give or take 45 degrees or so!

The trusty boat fired up like a charm. We spent a little like with the Coasties in there 733. They were breaking in a new crew, so just out burning tax-payer supplied fuel...

Sorry... no pics today. Lent the camera to a friend...

Have you dug out yet Pat?

[simmons0]

Originally Posted by Stoo

I have developed a few minor "dings" in my s/s prop from occasionally using it as a depth sounder. Do you think they make much difference to the performance of the boat? (Engine is a 150 Yamaha)

Is it reasonable to just grind them out, or should I send the prop into a "pro" for repair...?

I don't think anyone has pointed it out, but thats not a s/s one, so pretty cheap to replace.

[pathalla]

Originally Posted by simmons0

I don't think anyone has pointed it out, but thats not a s/s one, so pretty cheap to replace.

Don't know about that, Yamaha also makes black stainless props, can't remember what they coat them with...

[Stoo]

Actually it is stainless. I have no idea why it's black (mostly)....