I/O (Sterndrive) Conversion to Outboards

[tphoyt]

Sweet

 

[jlh3rd]

I made sausage biscuits and cracked open another bottle of gin. In the south, we just wait a day ot two. Much easier. Couple three naps a day.

in our borough, we are supposed to clear sidewalks 12 hrs after the "event". It use to be 24 hrs. This is BS of course. Typical "white tower" overreach.
Who/What determines the "end of event" ? And what does "clear" mean?

 

[tpenfield]

Quick Update . . .

I had a follow-up call with the Naval Architect yesterday. He is going to run a speed/power analysis on the new hull configuration, given that there will be 42" of additional planing surface.

We've had some discussion on the transom, as he indicated the need for a solid core in the areas of the engine mounts (G10 material, which is epoxy-based). I had some concerns about epoxy vs. VE as well as the need for a solid core vs. the Coosa as the core.

After discussion, the light bulb went on . . . . . . The combination of the clamping force of the engine bracket and usage over time will tend to depress the core, if it were a 'softer' material, and weaken the overall lamination. It's a longevity thing. (OK, I get it ) . . . the Coosa is much 'softer' than the fiberglass.

G10 is wicked pricey, ($650-ish for what I would need) and not entirely friendly with the VE resin, but the N.A. suggested that I could make the core if need be.

So here is the plan . . .
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I'll cut out the 2 'engine mount' areas in the Coosa board and 'fill' the voids with fiberglass . . . probably will use some vacuum-assist to get a good density of glass. Then the entire transom will get more glass to build it up to a desired thickness. . . and even more glass for installation.

Works in theory . . .

 

[Scott Danforth]

Ask him about Aqua Steel

 

[tpenfield]

Ask him about Aqua Steel

I did . . . (not familiar with it). A lot of these materials (Aqua-Steel, Whalelite) are more direct to manufacturer type of sales/distribution. G-10, GPO-3 and a few others seem to have a wider use-base and can be found at more suppliers.

 

[redneck joe]

So, overall just a wee bit off...

 

[alldodge]

Going to be great
Maybe why builders like Formula just buy the brackets from Armstrong

 

[Scott Danforth]

I did . . . (not familiar with it). .

I will ask the NA at work on Monday. He is the one that suggested Aquasteel with VE

 

[tpenfield]

I will ask the NA at work on Monday. He is the one that suggested Aquasteel with VE

No worries. I am good with making the fiberglass core as I described. I got enough extra glass and resin to make a decent core . . . and it will bond itself to the Coosa.

 

[tpenfield]

Going to be great
Maybe why builders like Formula just buy the brackets from Armstrong

I like how Formula does their OB versions . . . they extend the hull/planing surface out to where the swim deck ends, then go with a bracket from there.

I'm not a fan of their swim deck with OB's . . . at least on the 310-330 series. I think on the bigger boats the swim platform area is more thought out.

 

[tpenfield]

On to the Transom . . .

I cut out the two areas for the fiberglass insert. My plan is to glass one side of the cavities and then 'fill' the cavities with a glass/resin combination to be level with the open side.

Here is the glass layer of 1808 setting up on one of the cavities.
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There is a 1" thick Coosa board (and plastic barrier) clamped underneath to keep it all nice and flat.

 

[tpenfield]

In other news . . .

I got the Hydrostatic & Speed/Power (Savitsky) analysis back from the N.A.

Not 100% sure what I'm looking at, but overall it looks good. I'll be having a follow-up call with the N.A. over the next few days.

In summary . . .

• No adverse trim effects from the added stern buoyancy & planing surface.
• Estimated speed is 52+ MPH with twin 300 hp engines. (the current boat does/did 45 mph).
• Loads are as predicted and in accordance with the design.