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#2
10-05-2014, 09:24 PM
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Ah! Now I get it. I wasn't considering the most important part, and that is the boat moving forward on plane... Thanks for clearing that up. Of course that makes it a little tougher to deterimine how high the motor needs to go.
Maybe its better to just buy an adjustable bracket for that reason alone? If i don't get it right the first time, I need two more SS angles. 
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#3
10-05-2014, 09:46 PM
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 this is a bracket i made for my whaler. it was built for a 15" motor and when i repowered, i wanted a 20" in case i put it on any other boat. granted this is a lot less weight & hp, but you get the idea. the original transom is about where the starboard stops.
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#4
10-05-2014, 10:04 PM
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no we're ALL confused.. lol..
YES the further back the engine gets the HIGHER it must be... not because of the angle of the transom (you are measuring height above the keel not angle) The reason the engine gets higher further back is because the boat displaces water even on plane... the water right at the transom is lower than the water in front of and behind the boat... as soon as the transom leaves a given point in the water it immediately starts to rise towards it's original level so behind the boat is uphill.... ALSO the keel will be pointing uphill toward the front so straight back (no matter the transom angle which you build around) is downhill.... sooo your engine moving downhill where the water is moving uphill requires more lift.... You do not need any huge washers or plates on the transom... the angle iron will already be spreading forces much better than the outboard brackets... you only need the same washers you would need to mount the engine directly to the transom..... under power the only forward force on the transom is at the very bottom end of the bracket or angle... the top is pulling away from the transom..... ALSO nobody mentioned this but the bracket will not increase leverage on the transom... in fact it will lower it... the forces are at 3 points... prop shaft, bottom of bracket, and top bolts through transom..... a simple lever with the bottom of the bracket being the fulcrum the prop is the fat kid on the teeter totter and the transom top is the skinny kid..... the bottom of the bracket is the hinge and the top bolt is you.... by moving the prop up you have moved the fat kid closer to the hinge and made it easier for the skinny kid to lift him You don't HAVE to get it right the first time... your motor has the adjustability built in... just get your bracket close but not too high and adjust the engine up as needed for max performance Last edited by smokeonthewater; 10-05-2014 at 10:10 PM.
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#5
10-07-2014, 02:39 PM
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I think you are going to have trouble if you mix metals unless you can insulate that aluminum plate from the stainless angle, the plate will act like a sacrificial anode to the bracket, especially in saltwater.
__________________
Doug 87 Cuddy with a 94 Black Max 200! & a 1983 Cuddy, looking for power. Last edited by garbubba; 10-07-2014 at 02:41 PM. Reason: i'm an idiot
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#6
10-07-2014, 04:45 PM
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he has no need for an aluminum plate.... all he needs is angle and bolts
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#8
10-07-2014, 08:09 PM
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Buy this hull get a free jack plate, $300. Then flip the hull.
http://augusta.craigslist.org/boa/4694174420.html
__________________
1985 Wellcraft V-20, Evinrude ETEC 150: SOLD 1979 Marine Trader 44, twin Ford Lehman 120s 2006 Panga 14, Tohatsu 20
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#9
10-07-2014, 08:20 PM
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Not precisely. I asked how it should be built, and someone suggested to put a plate on the inside.
It's clear from this thread everything should be aluminum, and consensus appears that it isn't strictly needed. The force applied is greatest at the inside top bolts of the transom and the outside bottom bolts due to the whole thing essentially being a lever. The bolts are stainless only because aluminum bols aren't strong enough (if they even exist). I personally am uncomfortable using angle for an engine this size, I would feel better if it were at least "c" channel. That is just my gut feel, no actual numbers to back that up. But I have looked at pictures of Z-Lock for comparison. Most notably, the hi jacker design (which resembles the angle design) is rated up to 150hp. For larger engines, the design changes. The amount of force needed to move 2000lbs of boat, plus 1000lbs of fuel, people, and gear has to be significant ... Plus it must apply some amount of torque due to the prop. [EDIT] Just found this design that uses angle brackets here: Machine Shop Goes up to 300hp, so maybe angle is OK. I am stopping by a metal place Friday to see what is available and what it costs. Last edited by peiserma; 10-07-2014 at 09:28 PM. Reason: bobs machine shop
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