Slightly bent prop

[chrisk]

I was out for the last day of my season on Sunday and noticed a small vibration at certain RPM's. Finally remembered to look at the prop in the driveway yesterday and discovered a tiny bend in the tip of one of my prop blades. I feel like I should be able to bend it back or something myself, has anyone tried/succeeded at this? I really don't want to pay $100 just to get a tiny little bend fixed.

[lively]

i would heat it with a torch if you did try it ... i mean as long as its not half a EAR or something like that then u should be ok ... but deff get it hott and when i bend anything i use two hammers one to hit and one to hit against .... but if it was me i would just have it re balanced , they usually fix it

[wotan2525]

I've taken mine and laid it on a cement block and hammered the lip back flat.

It's not perfect, but it's better than running it as is or spending $100.

[michael hunter]

Inboards are very sensitive to any damage in the prop. I dinged mine this year and took it in for repair. When I got it back there was still a small vibration within the first 2 seconds especially pulling a load. I inspected the prop and it looked perfect. After checking out everything else I took the prop back for re inspection. They found one blade off a tiny bit you couldn't see by just looking at it . You can try and fix it yourself but if its not perfect it will shake other things apart.

[rludtke]

Blade track and balance is important to prevent bad vibrations. Vibrations will generate harmonics and harmonics could lead to a broken shaft if the frequencies are correct.

The prop repair shops anneal (soften) the bronze before they form the metal back into shape. Annealing removes all of the stresses built up in the prop. Then they harden the bronze again by the cold working (hammering) of the repair, and sometimes further hardening (strengthening) by additional heat treating as well.

By hammering out your bend, you will continue to cold work the metal but only in a localized are. Cold working, or work hardening as it is sometie called makes the metal harder. The harder the metal in a local area, the higher the stress. Stress risers could form in the straightend area, wich could lead to a prop failure. The prop shops have processes such as annealing to prevent stress risers during there repair.

I think that $100 for a prop overhaul is well worth it.

[michael hunter]

My Vdrive 4 blade was 165 to repair.

[csuggs]

I would not try to repair it myself because like others have said, you cannot see what really happens to a prop. It has to be balanced, etc. Here's a pic of my latest - brand new Acme prop. The bend looks only minor but it felt like it would shake the boat apart to run it. I sent it to an outfit calle Proper Pitch in Selbyville, DE (800-238-1462) For $85 they straightened and balanced it as well as do a dynamic study before and after repair. After getting it back it's better than it was new in April - I now get another 200rpm out of it and it's smooth as silk.

http://i887.photobucket.com/albums/ac71/csuggs/DSC03582.jpg