what is prop cupping

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bun Scotland
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what is prop cupping

Post by bun » 15 May 2025, 07:27

hi guys i was told if im going to fit a dole fin i need to get the prop cupping done sorry i dont know what this is its only on my 5 hp wee 4stroke on the wee sea kat any advice on this item off cupping
:thud
cheers guys

nala Wales
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Re: what is prop cupping

Post by nala » 31 May 2025, 14:33

Hi bun, this is a skilled procedure carried out to produce more thrust.Or reduce the lost thrust due to the flatter prop blade. Hence the term cupping.
If you imagine your hand(s) flat whilst your swimming you lose some of that thrust pushing water.
Now think of cupping your hand(s) again whilst swimming you have better control on thrust.
On a 5hp ? I would fit a greater pitch prop which has slightly less diameter.
Check what props are available.
The dole fin is usually fitted to reduce cavitation/ventilation and get the vessel up on the plain quicker. And is proved to have a stabilising effect whilst under way and coming about.
Take Care

bun Scotland
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Posts: 185
Joined: 14 May 2018, 08:46
Boat Make: boatworld 330 v floor
Outboard: tohatsu 4stroke 6hp
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Re: what is prop cupping

Post by bun » 19 Jun 2025, 05:18

nala
thank you very interesting

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