15-footer Seat Length

[Maverick]

[What is] the correct length of the (driver) mahogany (plank) seat on a c.1970-1980 Boston Whaler 15-foot hull models?

Thanks, Mav

[jimh]

The correct length for the thwart seat is short enough to fit under the seat retainer if the seat is resting on the lip molded into the hull liner, or long enough to fit above the seat riser if the seat is resting atop the riser. The thwart seat height changes with models and years. In early production the seat rested on the molded lip in the hull liner. In later production the seat was raised so it rested atop and was fastened to the seat riser. This added several inches to the seat height and provided more comfortable seating for most adults but required a long plank.

I don't think there are any 15-footers prior to 1976 or possibly late 1975.

The length of the thwart seat planks if cut to fit under the retainer and rest on the lip of the hull liner was shorter than the length for resting atop the riser. I had the shorter planks on my 1976 SPORT 15 and they were not long enough to change to resting atop the seat riser.

15-footers with SUPER SPORT interiors had much different seating.

[Maverick]

The boat I'm looking to 'thwart seat refit' is a 1976 Whaler 15. I don't have it here presently or I'd measure the distance and cut the mahogany accordingly. I have some time to kill in the meantime so was reaching out here for a number so I can have the seat ready to install at a later date.

I think you're telling me the length varies by year...guess I need to wait and measure this one unless a '76 owner on the forum can measure theirs and provide a number.

Thanks, Mav

[jimh]

I'd refit the seating so it rested atop the riser. The original c.1976 SPORT 15 seats were very low.

[Maverick]

Ahh, great suggestion...higher seat also allows more room for under seat gas tank.

Thanks, Mav

[jimh]

MAV--considering the cost today of good 5/4 Mahogany planks, I recommend not cutting any of them to a particular length that someone mentions on the internet to be the right length before you actually get the boat and can measure. If you cut a plank too short, you can't recover from that error very easily.

[dtmackey]

I agree with Jim, the seats are too low. My 15 SuperSport is a mid to late 80s model and it felt like you were sitting on the floor. I fabbed a custom interior and raised the seats 1.5" with attached wood cleats underside the thwart seat to achieve the desired height and it worked great. I'm still in process on the Whaler rehab, but would be happy to share comments and pics that I have.

D-

[Maverick]

This morning I measured the rear thwart seat (mahogany plank) on a 1977 Whaler 15 from the outer edge to outer edge of the vertical (and long) mahogany riser that runs aft to forward on both sides: 54 inches. The width of the seat (mahogany plank) was 11-1/4"

Just curious...wonder what other years this size fits...could be a nice bit of info for the Reference section. Mav

[Maverick]

Interesting link I just found on thwart seats...this seller indicates dimensions of Dimensions: 53 3/4" x 11" x 1", will "fit all 13' & 15' hulls from 1958 - 1999".

I guess for about 40 years the sizes are the same...didn't know that.

http://www.specialtymarine.com/BOSTON-W ... p1037.html