Replacement tower for 2002 SANTE

[DJew Jake]

So I noticed this morning the front leg of my tower is cracked right by the mount to the boat. I had a buddy int he same position, he tried to reweld it twice and they both recracked.

I always thought there were major issues with the original design so now i plan to have a buddy of mine make me a new one out of stainless steel.

I am going to copy the footprint, using the same mounting locations, the biggest difference will be im going to goto a large piping, probably an inch large, for strength and stability.

The lower non folding part will have the same design, on the upper part that folds i am wondering if there would be any issues with raising the structure an additional 8 inches for better headroom from speakers etc, will this put considerably more stress on the deck of the boat? If so, i could always drop the rope attachment a few inches but still have the higher structure for speakers right?

[ryan351w]

Yes it will defiantly increase the load on the deck.

"considerably" probably not. But I guess that has to be defined.

So its a simple calc. T=FI
T=torque
F=force (applied to rope attachment)
I=Moment arm (distance from deck to attachment)

I know my tower is about 5' from the deck surface. For easy calculation I used inch/lbs and converted to ft/lbs.
The one variable here is how much load is actually seen, at the dead dig deep water start it will see a lot, as well as a big heavy cut.
I have no idea what it sees, so I took an arbitrary number of 400lbs.
Hmmmm may have to bring home a load cell and data acquisition setup and do a little experiment next summer.....

So T=400lbx60inches
T=24,000inlbs
converted to ft/lbs 24,000/12=2000ft/lbs

ok increase of 8"
T=400x68 27,200/12 2,266ft/lbs. so an increase of 266lbs.

that's about 13%

on another note, if you increase the tower 8" for the speakers but step down for the rope attachment, the load still has to go through that higher point of 8" so the load on the deck will be the same, but you've introduced a compounded torque on the tower joints.
Actually, it would do a lot more than that, there would be contradicting torques within the system and I'm not sure the overall effect it would have on the boat deck itself.
Moral of the story, don't do that part.
sorry was just "typing/thinking" out loud there.

Ryan