I/O (Sterndrive) Conversion to Outboards

tpenfield

tpenfield

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For those contemplating making a thick plate of fiberglass as I am doing . . . Don't :ROFLMAO:

My method has been to lay up CSM & 1708/1808 in alternating layers. I was originally thinking about 22 +/- layers. When I get to 3/4" of build-up, I place some plastic sheeting over the fiberglass in the cavity and use the 1" Coosa piece that I cut out as a 'tamp' and apply some weight to flatten the fiberglass out, so that it is even. Here is a picture of the cavity filled to 3/4" , 'flattened', and cured. . . . It has about 1/4" more to go to be level with the surrounding Coosa.
IMG_9145.JPG
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Since my shop is fairly cold for fiberglassing (60˚F), it takes a while for the resin to 'kick' . . . but once it does . . . holy cow . . . quite a bit of exotherm ! :oops:
The piece gets up to about 120-130˚F.

After curing, I add more layers of fiberglass to get up to the 1" thick. What I am finding is that I need about 25-26 layers of glass to get to the 1" . . . probably because of the CSM layer is not as thick as the 1708 and 1808 layers.

I hope to be done today with the inserts and then moving on to the next thing . . . which may be glassing in of the planing surface.
 
Scott Danforth

Scott Danforth

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Hey Ted, Mercury is showing the new 808 hp outboard at Miami. you could get by with one motor.
 
tpenfield

tpenfield

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flashback said:
Getting pretty heavy eh..:)
Click to expand...
Yes . . . But all for a good cause :p

My latest estimates, based on the recent changes are

Bracket ~ 500 lbs.

Hull Modifications/bracing ~ 200 lbs

Very little weight reduction overall . . . about 200 lbs.
 
Scott Danforth

Scott Danforth

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Ted, how many cases of beer will fit in the bilge where the two 6.2's used to sit?

Did you figure in the weight of "provisionings" in your calculation?
 
tpenfield

tpenfield

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I got the transom inserts done . . .

Here is a picture of the process . . . rolling out each layer to ensure that there are no air pockets. I add the resin (~ 5 oz. ) for each layer and then lay the cloth on top of it so the resin soaks upward into the cloth (or mat), forcing the air out.
IMG_9147.JPG
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It is a tedious process, but it works. I calculated the glass-to-resin ratio using a volume calculation. Each cavity is 275 cubic inches and I used a gallon of resin (230 cu. in) on each. So, the glass content is about 16% by volume. It seems pretty low, even though I painstakingly rolled the glass to force the resin up from the layers below.

Here is the transom with both inserts glassed.
IMG_9148.JPG
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alldodge

alldodge

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Looks good, did ya ever think about aluminum plate or honeycomb aluminum plate?
 
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