Reshape and Balance Propeller?

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For minor gouges and bent edges, you might get away with, but getting one blade badly out or out of balance can ruin the TBS bearings/ seals in the lower unit. I have done quite a few over the years, but non ever bad enough to require welding.. As a skilled toolmaker I had acess to the equipment to shape, and match the blades to each other as well as balancing the finnished prop. Small little nicks and gouges along the edges are usually not a big issue, but when you get into props that have material missing, that can become a real big issue !
I appreciate your valuable insights on prop damage and repair! Your experience as a skilled toolmaker definitely gives your perspective weight. According the post from https://en.tradebearings.com, I completely agree that minor imperfections may not be cause for major concern, but significant bends, missing material, or imbalance can lead to serious problems like vibration, cavitation, and ultimately, damage to the lower unit and seals.
 
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I'm sure "tearing up the lower unit" would be a costly mistake, but isn't the risk more likely that you'll tear up a seal and a bearing? How costly and hard would it be to replace these items? Bet a lot cheaper than a new prop.

I'm going to repair the prop on my Merc. Maybe I'm the dummy here, but it doesn't seem like rocket science to me. Mine has only light damage though and I'll attempt to balance it as best I can after most likely brazing over the scuff and grinding it smooth. The slight bend I don't think will be much of a problem working out.

My thinking is the only pristine props I see are new out of the box. If it's on a boat and it's used around here it's pretty much a given it'll have some damage. BTW there are some really good youtube vids on DIY prop repair. Seems a lot of people roll the dice, but I don't see many regretting it.
 
I'm sure "tearing up the lower unit" would be a costly mistake, but isn't the risk more likely that you'll tear up a seal and a bearing? How costly and hard would it be to replace these items? Bet a lot cheaper than a new prop.

I'm going to repair the prop on my Merc. Maybe I'm the dummy here, but it doesn't seem like rocket science to me. Mine has only light damage though and I'll attempt to balance it as best I can after most likely brazing over the scuff and grinding it smooth. The slight bend I don't think will be much of a problem working out.

My thinking is the only pristine props I see are new out of the box. If it's on a boat and it's used around here it's pretty much a given it'll have some damage. BTW there are some really good youtube vids on DIY prop repair. Seems a lot of people roll the dice, but I don't see many regretting it.
Roll the dice, time will tell the tale if you made the right decision or not! I have seen it before and no matter how much you think about it a decision has to be made, had customers lose their lower unit to damage, have had them not have any issues, had a few need to replace seals and bearings as well as entire lower units.
 
I'm sure "tearing up the lower unit" would be a costly mistake, but isn't the risk more likely that you'll tear up a seal and a bearing? How costly and hard would it be to replace these items? Bet a lot cheaper than a new prop.

For me it is better to buy a new prop because I wouldn't know where to begin replacing seals/bearings on the prop shaft. Probably simple enough to a lot of folk. I just don't have the skill set. I doubt I could get it in and out of any shop around here for less than the cost of a new prop.
 
I'm sure "tearing up the lower unit" would be a costly mistake, but isn't the risk more likely that you'll tear up a seal and a bearing? How costly and hard would it be to replace these items? Bet a lot cheaper than a new prop.

I'm going to repair the prop on my Merc. Maybe I'm the dummy here, but it doesn't seem like rocket science to me. Mine has only light damage though and I'll attempt to balance it as best I can after most likely brazing over the scuff and grinding it smooth. The slight bend I don't think will be much of a problem working out.

My thinking is the only pristine props I see are new out of the box. If it's on a boat and it's used around here it's pretty much a given it'll have some damage. BTW there are some really good youtube vids on DIY prop repair. Seems a lot of people roll the dice, but I don't see many regretting it.

Those failures tend to snowball. Prop seal leaks, lower unit fills with water, bearings fail, then all of the gear clearances are out of whack and chew themselves up.

BTDT when I put a thrust washer in the wrong place on a 25hp OMC and turned the lower unit into scrap metal through the course of an afternoon.
 
I hear you guys. Sometimes I'm too cheap for my own good, but seems like should be able to tell if it's bad out of balance. I saw a vid where a guy spun it with a drill to see what it does at speed. It was nice and smooth so he called it good. Other factor for me is I may well sell that boat if something better comes along.
 

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