Prop nut anode

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Cuan

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I want to fit a prop nut anode as I am getting some pinking on my prop and there is no room for a shaft anode. The problem is that the thread on my prop shaft is 16 x 2mm thread. The only prop nuts and anodes I can find are Vetus or Radice 16 x 1.5mm. I would be grateful for any guidance on this, either for the 2mm thread or as work around this.A an alternative are there any anodes that will fit a castellated nut. I haven't been able too find anything.
 
You could get an insert made with a thread of about M22 on the OD and 16x2 on the ID to fit your shaft and have the Radice or Vetus anodes tapped to fit the M22.
I'm a machinst and can do this for you but any local machine shop will be able too. I don't know how approachable Vetus or Radice are about making you a special?
I have got a lump of 50 mm DIA zinc here that I could make you a custom Anode.
 
Cuan said:
I want to fit a prop nut anode as I am getting some pinking on my prop and there is no room for a shaft anode. The problem is that the thread on my prop shaft is 16 x 2mm thread. The only prop nuts and anodes I can find are Vetus or Radice 16 x 1.5mm. I would be grateful for any guidance on this, either for the 2mm thread or as work around this.A an alternative are there any anodes that will fit a castellated nut. I haven't been able too find anything.
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Anodes on the nut are not very effective as they are inevitably very small. Suggest you use a hull mounted anode bonded to the prop shaft. This is usually done by wiring the anode to the gearbox housing and if necessary bridging the coupling if it is the flexible type.

BTW your thread is a non standard size.
 
Thanks very much for the offer. I am on the trail of a 16x2 nut and will see how that goes. I want to go with some sort of standard arrangement if i can, to make future replacements easy.
Thanks though.
 
Tranona said:
Anodes on the nut are not very effective as they are inevitably very small. Suggest you use a hull mounted anode bonded to the prop shaft. This is usually done by wiring the anode to the gearbox housing and if necessary bridging the coupling if it is the flexible type.

BTW your thread is a non standard size.
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I have got a hull anode but can't find the connection inside the hull. I think you might be right and i should concentrate on getting that bonded to the prop shaft.
 
Tranona knows his onions when it comes to this sort of stuff.(even if it does mean my Grandson will have to go without a B/day present this year now :D )

Just one thing Tranona. You say his thread isn't a standard size... It is standard metric course, or do you mean non-standard for a prop shaft?
 
colhel said:
Tranona knows his onions when it comes to this sort of stuff.(even if it does mean my Grandson will have to go without a B/day present this year now :D )

Just one thing Tranona. You say his thread isn't a standard size... It is standard metric course, or do you mean non-standard for a prop shaft?
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Non standard for a propshaft. The norm for a 22 or 25mm shaft is M16*1.5 - which is why the anode nuts are that size. Might be worth talking to Lake Engineering to see if they have blanks they can cut a matching thread in. The nuts have a boss on the end which is threaded and the anode is attached with a set screw.
 
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You would remove your existing castellated nut & replace it with the special nut from the kit. Cotter pin goes thru the slots in special nut.
Next year,you replace only the zinc by removing allen screw.
 
Len Ingalls said:
You would remove your existing castellated nut & replace it with the special nut from the kit. Cotter pin goes thru the slots in special nut.
Next year,you replace only the zinc by removing allen screw.
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That is what you have to do with an anode nut anyway. The issue is that the special anode nuts for his size shaft have a different thread from his shaft. once the nut is in place you attach the anode to the boss with a screw.
 
Len Ingalls said:
You may have a SAE nut & thread. 16mm = approx 5/8" Thread would be 5/8" OD x 11 Threads per inch-standard size for a 7/8" OD shaft-common in N.America. Prop nut Zincs of that size(and others) are common also & work as well as any zinc,though they should be replaced annually.
http://www.kiwiprops.co.nz/cms/index.php/resources-general/sae-shaft-standards


http://www.boatzincs.com/prop_nut_specs.html

http://www.martyranodes.com/content/index.php
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Thanks for this. I have had the nut measured up properly and it fits a 16x2mm thread. Non standard, but thats what it is.
 
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Tranona said:
Non standard for a propshaft. The norm for a 22 or 25mm shaft is M16*1.5 - which is why the anode nuts are that size. Might be worth talking to Lake Engineering to see if they have blanks they can cut a matching thread in. The nuts have a boss on the end which is threaded and the anode is attached with a set screw.
Click to expand...

I had spoken earlier today to Lake Engineering and they were very helpful and have tracked down a 16x2mm thread nut and anode, now on order. Will also check bond to the hull anode for better protection.
 
lydiamight said:
If you don't have any luck with Lake Engineering then try these people http://www.zincsmart.com/

Click on the "prop nuts and anodes" section. They don't list 16X2 but do say "Nuts are available un-threaded, they can be machined for fitting to other shafts."
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Thanks for that, I have bookmarked the page for future reference. Lake Engineering are sending me a nut and anode next week, so all should be OK now
 
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