Fin keel length Beneteau First 305

[karlfaeunst]

I was wondering if anyone knows the length of the standard fin keel on the Benny first 305.

Thanks

 

[pvb]

You'll get a near-enough figure by scaling it off a diagram of the boat.

 

[Laurie]

According to "SailBoatData"....1.7 metres????? (presuming you meant depth and not chord?)

 

[lustyd]

Thanks Laurie, Yes 1.7m is the draught but what I was looking for was the actual length of the keel so I can put in the correct offset from the transducer. I did as PVB said and work it out to be about 1.4m give or take an inch or two.

Use a lead line to work out the actual depth then set the transducer to that. You know the draught so the length of keel is not relevant here. The reading on the display should be either depth of water or depth of water - draught

 

[lustyd]

Aha! Yes but what I'm looking for is depth under the keel or under keel clearance.

Yes, as I said that's your depth of water - draught. It makes no difference where the sounder is as long as the display has the correct number, and the correct number as you just said is depth - draught.

To do this, use the lead line to find the actual depth of water - this is the most accurate way to get the information. Then subtract your draught to give the number you're looking for. Next, change the offset on the box until it reads that number. No need for complexity and multiple offsets at all. When finished you'll even know the length of keel as it will be the offset you entered to get the right number!