I/O (Sterndrive) Conversion to Outboards

Scott Danforth

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Fairing is the correct term for slapping body filler on the fiberglass and making it ssmmmmoooooottthhhhhh
 

tpenfield

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Fairing is the correct term for slapping body filler on the fiberglass and making it ssmmmmoooooottthhhhhh
In search of flatness. . . .

OK, the transom as it is now is not very flat.
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IMG_9363.JPG.
IMG_9362.JPG.
Most likely from lamination overlaps, etc.

I am not sure fairing compound (I have a source for VE fairing compound), is the right thing for the mounting area of the outboard. . . but maybe it is. :unsure:

'Plan B' would be to take a 'flat' piece of something, bigger than the OB mount footprint, and mix up some fiber-strand paste and use the flat piece as a 'surface mold' to give a nice flat area, just where needed.

I think I would need about a 20"x15" piece of flatness based on the engine mount footprint.
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Honda-BF350-Mount-2B.png
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Thoughts? :unsure:
 

Scott Danforth

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Ted, make some PB and use that to fair the surface vs micro-spheres

your fiberglass shop will also have kitty hair or tiger hair
 

tpenfield

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Do they have a measurement for how flat it needs to be like the I/Os?

Do they have a measurement for how flat it needs to be like the I/Os?
I believe the I/O spec is thickness and how 'parallel' the inside & outside surface need to be.

I'm trying to find what outboard motors need, but I would imagine it mainly applies to the outside surface.
 

Scott Danforth

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I believe its supposed to be flat within 1.5mm over a 1 meter length (with a straight-edge). but that is memory.

then I recall a 3mm parallel requirement (which doesnt make sense for parallel)

I would want the transom flat where the motor clamp sits on the outside from a loading standpoint.
 
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