Propeller nut tab washer material.

sharpness

sharpness

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Looking at prop nut tab washers for conventional shaft drive (bronze prop and nut fitted to stainless steel shaft) I've just seen that most tab washers are made from 316 stainless, and some are offered as zinc metal plated of which i recently purchased. I assume the zinc metal plated must be suitable, I'm thinking along the lines of cathodic, galvanic corrosion etc ? Thanks in advance for any replies / advice.
 
vyv_cox said:
Galvanic corrosion is not going to be a significant problem with such a small item. Stainless might not be ductile enough for repeated bending. 70/30 brass sheet might be good. Mostly though galvanised sheet is the choice.
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They are not sufficiently ductile and can break on the second use. But they do come with multiple tabs, 5?, and you only use 2 at a time, But they are so cheap, I buy a few and use them as one use only. However being parsimonious I keep the old ones incase I have to take the prop off and need something short term.

Never seen a gal tab washer - maybe I need to get out more :)

I'd rather a tessalated nut and cotter pin
 
Neeves said:
Never seen a gal tab washer - maybe I need to get out more :)
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Thanks. Ref zinc metal tabs, see link below (y) I have absolutely no issue with company or product supplied, just wanted to check I'd purchased correct product, bearing in mind most other suppliers seem to offer stainless 316. As mentioned by vyv cox, a valid point is the bending of stainless tab washer has to be taken into account.

Propeller Nut Tab Washer
 
I just buy a few of the Volvo tab washers. They are different to those in Sharnness link in that they have, I think, 5 tabs. I simply don't recall how much they cost (I'm sure a lot for what they are) but not enough to lose any sleep over. I did try to use the same tab twice, once - it did not fail when I bent it over the second time but did crack - so I discarded that tab.

Propellors are expensive, very, and I also use blue Loctite and the tab washer. On the Volvo prop, the one we have, there are 2 nuts, one is quite small the other is large and I had to buy a large individual socket to fit as my socket set simply did not go that large. (I don't recall the size)

And Gary - your link does not work. :( - or not for me

Jonathan
 
I recently saw a boat ashore where all the tabs were knocked down against the flats of the prop nut. Don't remember what material the tab washer was made from. All I am saying is that the washer served no purpose what so ever. The washer would simply rotate with the nut if the nut ever came loose.
 
sharpness said:
Looking at prop nut tab washers for conventional shaft drive (bronze prop and nut fitted to stainless steel shaft) I've just seen that most tab washers are made from 316 stainless, and some are offered as zinc metal plated of which i recently purchased. I assume the zinc metal plated must be suitable, I'm thinking along the lines of cathodic, galvanic corrosion etc ? Thanks in advance for any replies / advice.
Click to expand...
Here a simple mild steel is what if commonly used. It lends itself to bending into position.
Corrosion is hardly a problem, give it a few coats of a protective paint if your concerned by next years antifouling or a bi annual one.
Other metals tend to partly fracture, good old mild steel doesnt.
 
Cleanhull said:
Here a simple mild steel is what if commonly used. It lends itself to bending into position.
Corrosion is hardly a problem, give it a few coats of a protective paint if your concerned by next years antifouling or a bi annual one.
Other metals tend to partly fracture, good old mild steel doesnt.
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And never re-use a locking tab would be my recommendation.
Alternatively s/s wire locking if you can drill the necassary hole through the nut.
 
SteveIOW said:
I recently saw a boat ashore where all the tabs were knocked down against the flats of the prop nut. Don't remember what material the tab washer was made from. All I am saying is that the washer served no purpose what so ever. The washer would simply rotate with the nut if the nut ever came loose.
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No it won't as there is another tab that bends the other way into the keyway. You can clearly see it in the attachment in post#8.
 
Tranona said:
No it won't as there is another tab that bends the other way into the keyway. You can clearly see it in the attachment in post#8.
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Thats correct, there are variations in locking tabs depends on the application, but all have the secondary leg or locking tab without which it would of course just be a 'washer'
 
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