Shaft Replacement - Interesting Vendor

[waterdog]

First haul out since repower.   I had been having some vibration at higher revs.   Decided to bite the bullet and replace cutlass bearing.  There is some play.   I thought it was time.    Boat yard suggested they would likely cut the shaft out to do cutlass bearing rather than messing around with coupling etc.   I wasn't sure I wanted these guys touching my shaft so to speak. 

The old bronze one was scored near the packing gland, so I decided it was time to do the whole thing.  The yard recommended a machine shop for the shaft.   Having read Mainesail's notes on shafts and couplings, I was a little particular about whether the machine shop knew what they were doing.

Was I ever surprised.   The owner's grandfather, a boatbuilder, died in 1930.  Grandma ran the shop through the depression until the oldest boy finished school and started full time.   Somewhere in the 40 or 50's they decided to drop the line of Palmer engines and focus exclusively on shafts.   That's all they have done for 70 years or so.   They're on their 4th generation.   It was huge shop.  One lathe bed had to be 24 feet long. 

He patiently listened as I made my requests for the interference fit, dressing the end of the coupling, etc.   As though there was some other way to do a shaft.  We had a long chat about alloys.   A day later I have thing of great beauty at a reasonable price.  The place was so old school they ran my credit card through an imprint machine and dialled in the number on a touch tone phone to get an approval code. 





 

[KWKloeber]

A day later I have thing of great beauty at a reasonable price.  The place was so old school they ran my credit card through an imprint machine and dialled in the number on a touch tone phone to get an approval code. 

Are you keeping this Gem of a craftsman a secret all for yourself?   

You can of course, change out a cutlass w/o taking out your shaft (so to speak    )

https://www.youtube.com/watch?v=5BKdBXHIyC8
https://www.youtube.com/watch?v=xa78umBAUAc
https://www.youtube.com/watch?v=GZQHLvUUyuE
https://www.youtube.com/watch?v=BSsAO5yE1Kw



Cheers,
Ken


 

[waterdog]

VM Dafoe.  I would give you their website address, but uh, there isn't one...

Even the coupling was a custom job with their own casting.     No set screws.   Kind of a split collar with through bolts keyed into slots in the shaft.  I better take a picture...

[waterdog]

Here is what the coupling looks like...

[KWKloeber]

Here is what the coupling looks like...

SWEET- looks similar to a standard Buck split coupling, but no doubt better.  Split couplings (when done right) are so much easier when you (hopefully never ever have the need again to) remove the shaft.  

Looks like a FIRST CLASS machine shop you have there -- Dafoe is in V, BC, I presume?  

No set screw at ALL?   Hmmm... I'm not sure I agree with that approach..... All the splits I have seen have at least one set screw as a backup/fail safe (should be set into a dimple drilled in the shaft.)

OR maybe I am misunderstanding -- are you saying that the bolts themselves fit into a machining near the the end shaft?  If so, that is defo a FAIL SAFE!


Ken

[waterdog]

The shaft has two notches (and a key).    The coupling bolts go into the notches.    Both bolts must be completely removed for the shaft to come out.   It looks pretty bullet proof.   I think they know what they are doing.

How important is it to lap the prop on the shaft?   If I skip this step, will life as I know it come to an end?   

I did read some good stuff about making sure the prop isn't sitting on the key.    Put prop on mark end of travel, remove and pull key, put prop back on and make sure it seats the same.    That seems like a good idea.   

[KWKloeber]

You should defo lap the prop, ESPECIALLY with a new shaft, but should be done any removal to be sure.

Easy. quick, and cheap - A DIY.  See MaineSail's procedures...

Ken