I/O (Sterndrive) Conversion to Outboards

[tpenfield]

Ribs, gussets, and bolts. . . .

While away, I did some detailed drawings of the extension pod and support structure. Yellow is the boat's structure and gray is the extension pod and support structure.
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I am going to add a bunch of gussets to support many of the flange areas where the bolts will go. Some ribs to stiffen the long horizontal runs, . . . and lots of bolts, distributing the load.

In total there will be 74 gussets, 16 ribs, and 78 bolts. Since there are so many bolts planned, I am thinking 3/8" fine thread hardware (316 SS).

 

[alldodge]

Assuming flat washers and lock nuts?
Why fine thread, isn't it easier to over torque a bolt using fine?

 

[redneck joe]

And being a simpleton wood guy, more nails isn't better. 78 seems alot, but im not any kinda smart guy.

 

[tpenfield]

Fender washers and regular washers with unlock nuts.
I figure fine thread is better for both tightening and not loosening

 

[Pmt133]

I thought fine was more subject to loosening than coarse... but it's been a long time time since I did materials. Beyond that in the scope of pedestrian hardware I don't know there is much a difference between coarse and fine otherwise. I prefer fine as they nuts seem to thread on easier. No other reason lol.

 

[tphoyt]

I’ve always felt like there is more surface area being covered with fine threads and they are less likely to vibrate lose. Just my thoughts.

 

[redneck joe]

Don't you double nut and goop the threads?

 

[tpenfield]

Transom assembly is fine thread, outdrive to bell housing is fine thread.

Must be a reason.