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milkmania
02-28-2006, 11:28 AM
took the old prop off of my PS190 Powerslot 1 1/8 shaft....
saw that it had a steel or stainless steel key.

Was looking in a mail order magazine that listed a prop pulling kit, included was the Nylock nut & brass key.

I'm thinking the softer brass key would function as a shear key? Is this correct? or it just for corrosion/electrolysis benefits?

jeverett
02-28-2006, 11:37 AM
I would have to say most likely it is included for it's shear properties, but I think that if you hit something hard enough to shear the key you are pobably going to waste the prop. Brass is not sacraficial (ion exchange) enough to prevent corrosion.

Leroy
02-28-2006, 11:42 AM
You're right, softer so it doesn't damage the shaft or prop as much.

milkmania
02-28-2006, 11:47 AM
thanks for the replies

do you think it's worth the trouble replacing the steel with a brass one?

I'll probably check around and see who's got any brass stock:(

you think a nut & bolt dealer would carry the Nylock nut?
or probably a dealer item?

Tom023
02-28-2006, 11:47 AM
Brass key at my prop too. Key in the coupler end is steel.

milkmania
02-28-2006, 11:48 AM
Brass key at my prop too. Key in the coupler end is steel.

noted, thanks:)

TonyB
02-28-2006, 12:25 PM
took the old prop off of my PS190 Powerslot 1 1/8 shaft....
saw that it had a steel or stainless steel key.

Was looking in a mail order magazine that listed a prop pulling kit, included was the Nylock nut & brass key.

I'm thinking the softer brass key would function as a shear key? Is this correct? or it just for corrosion/electrolysis benefits?



To quote this site (http://www.bertram31.com/proj/tips/shafts.htm),
"Also, never use a stainless steel key in the prop end of the shaft, use a bronze key which is more forgiving in case you run aground or strike some other submerged object with the wheel... "

DanC
02-28-2006, 12:46 PM
It may sound logical, but if you look at the design of the prop shaft key, there is no way it is going to give if there is a prop collision. It is not designed like a shear key. Those of you who have run aground can verify that a 1 1/2" shaft key is not going to shear or even appreciably give way in the longitudinal direction before your prop blades are at the bottom of the lake. The prop key will not come into play in a more signifcant strut/shaft/hub strike.

However, I would go with the brass key for assembly and dissassembly reasons. If that key ever gets jammed, such as from a minor prop strike, you want the key to not ding up your SS prop shaft.