Ship Shape TV

[John R]

Anyone just see this afternoon's SSTV? They pulled some sea drives off an older Pursuit and put on a twin Armstrong Bracket and a couple Rudes. Well, they kept going back to a small shot of them fishing on that Yellow Seabird. Did anyone see how far below deck that boat sat in the water? With a float chamber and a single + two fat guys, the water line looked 6 inches OVER the floor height

[Capt Chuck]

John

Last night they showed that episode here in Fl on Adelphia cable. I don't recall seeing the Yellow boat flashbacks [img]/images/graemlins/confused.gif[/img]

The one aired showed removing the OMC Seadrive and mounting the Armstrong double wide bracket for a pair of 175hp rudes. Also it included Armstrong's CEO showing their brackets since 1984. What impressed me was their new option of the lights for night fishing and diving which were mounted in the flotation tub at $500 [img]/images/graemlins/wink.gif[/img]

[Scott]

John ...The deck of the bracket was under water by 6" ?? [img]/images/graemlins/shocked.gif[/img]
I think (not that it matters) they used a Stainless marine bracket on the Seabird...

Anyone know the buoyancy #'s on the other brackets .... Stainless, Armstrong??

[pogden]

Scott said....

Don't forget on a bracket the motor gets mounted higher than it would on the transom anyway due to rate of rise of the water coming off the bottom and the setback of the bracket....

What is the equation for the setback verses the height?

Is it raise the motor a 1/2 inch for every inch of setback?
So for a 30" set back the motor would be 15" higher??? I'm confused??? [img]/images/graemlins/confused.gif[/img]

[lost2a6]

What is the equation for the setback verses the height?

Is it raise the motor a 1/2 inch for every inch of setback?
So for a 30" set back the motor would be 15" higher??? I'm confused??? [img]/images/graemlins/confused.gif[/img]

[/QUOTE]
I think that for every 5" of set back you go up 1". You can get away with a little more height with the greater amount of V that you have.

[Scott]

What is the equation for the setback verses the height?

Is it raise the motor a 1/2 inch for every inch of setback?
So for a 30" set back the motor would be 15" higher??? I'm confused??? [img]/images/graemlins/confused.gif[/img]

½ inch for every inch setback ??? that’s a problem [img]/images/graemlins/shocked.gif[/img] …are you sure it wasn’t a foot?

What I've been told by a couple different builders (using Stainless brackets )was 3-5 inches to start …….1-2” rise for every foot of setback…..so to average it for a 30” set back …2.5 x 1.5 = 3 ¾ “ rise ( but I'm guessing the amount of rise changes with every hull out there) This is a ballpark ... then adjusted up/down once the boat is sea trialed

I also believe this is how you get the shallower running drafts ….. not the that bracket is physically lifting the stern of the boat out of the water ( remember chances are that the bracket buoyancy gets cancelled out when the engine gets mounted anyway and conversely canceling the effects of the engine/s weight)… but rather the engines draft is less due to the higher mounting position as opposed to where it would be when mounted on a notched transom.

I don’t know how this works with Seamark ….as we know the bottom of that bracket follows the same plane as the hull ….. Unlike the Armstrong (although I have seen the Armstrong shape change) or the Stainless that angle up towards the motor mount

I don’t know how that effects the flow of water aft of the transom when it meets the brackets floatation chamber ….. I thought in one of my conversations with Don that the bottom of the bracket is mounted 3-4 inches higher than the bottom of the SeaCraft 23 hull...I'm assuming the Seamark was designed around the 23 SeaCraft

[John R]

The seamark is not completely flush with the botom of the hull - tough to see but it looks like a 4-5 inch step from the bottom of the hull to the bottom of the bracket

[Mark]

I think one key point of the Seamark vs. Armstrong debate is that the bottom of the Seamark bracket is parallel to the bottom of the boat rather than angling up as it moves aft. If floatation matters anyway.

[laser]

The seamark floatation is 800 lbs. I don't think Armstrong can touch that. On my boat the hole shot was flat...the seamark was like a giant tab and you trim up the engines and the boat takes off [img]/images/graemlins/grin.gif[/img]

Bill