21 Hull #136...Restoration...Started

[Bushwacker]

First class work Terry! Looking really good! Sounds like holding off on final deck attachment was a wise decision!

How will you attach the front floor panels that support the seats? (Just thinking out loud here, but since the panel width is much less than length, the vertical reaction loads along the panel edges, required to balance the side loads on the seats when the boat starts rockin & rollin, will be much higher along the sides than on the ends. However you'll also have more surface area along the sides for screws/adhesive, etc. so likely not a problem, especially if you have a substantial cleat along side of hull.)

On the flotation foam - most boats that sink end up capsizing and floating upside down because all the foam is in the bottom. I've always thought that it would be better to use a lot of the space below the cockpit sole for stowage, fish boxes, bait well, etc., and put all the foam up in the coaming/gunnel area so if the worst happens, it'll float upright! There's a fair amount of volume in the coaming on a Seafari. Inflatable air bags might be another option. Denny

[Islandtrader]

Denny thanks for the input...to answer your 2 questions I was originally going to just tab the front floor piece down since the sides have a fair amount of solid contact. However your comment gave me and idea and what I will do is bond a cleat down and then attach the front lip to the cleat and then tab.

See pictures below.

Front Lip of floor





Cleat






Tab and bond



As far as the flotation where the noodles are very little usable space. However after all the rod holders,cleats and etc. are installed I will cut up a few more noodles and put them under the gunnels....another good idea. Also there should be a ton of space under the rear cap.

With that and hopefully a couple half full tanks the boat should not go to the bottom if a disaster happens.

[seacraftks]

Beer sounds good

[Bushwacker]

Hey Terry,

I'm having trouble getting myself oriented on those latest pictures you posted, I guess because they're such close ups. (all I can see is trees and roots, can't see the forest!)

Anyhow, let's see if I can explain my concern a little better. If I understand you correctly it looks like you're planning to secure that front panel that'll hold the pedestal just at the front and rear and maybe at the cleat on the hull side, but what about along the inside above the gas tank/stringer?

I know how small boats can rock and roll when you're offshore in the slop, and I'm sure that 21 will be more stable than my 20. However, my concern is dynamic loads and the twisting moment that pedestal will put into a relatively thin (1/2"?) flat panel that, by itself, is not very stiff in torsion. The loads can get real big really fast! (Connor's comment about his pedestal breaking off at the weld on his last Bahama trip started me thiking about this!) Let's say your pedestal is 3' tall and it's mounted in center of a floor panel that's 4' long and 2' wide, assume that you weigh 200 lbs, and that you get hit by a freak wave or wake while you're trolling along offshore that rocks the boat suddenly enough to impart a snap roll of about 2g's. (I've done a 2g barrel roll in a T-34 and it's not that violent; I'll bet 3 or 4 g's is not unrealistic, and as high as 8-10 g's in fore & aft pitching motions! For reference, USN carrier aircraft are designed for 10g vertical loads during landings, generally considered to be controlled crashes!) A 2g dynamic load means you'll temporarily weigh 400 lbs x 3' = 1,200 ft-lbs of torque going into that floor panel! Let's say the panel is only fastened at the sides, just to simplify things. To balance the 1,200 ft-lb twisting moment the pedestal is putting into the panel with an equal and opposite load along the sides, you'll have to have 600 lbs of load along each side of the panel, pushing up on one side and down on the other. The point is, I don't think it'll break, but it might feel surprisingly "wimbly"! I think it wants to fastened down along all 4 sides. The loads on the pedestal screws will be even higher for the same reasons, but I think you've added enough beef under the panel for that. You might even try mounting a pedestal seat on that panel and temporarily mounting in boat and rocking it around to see if it feels solid enough.

For comparison, I discovered when I installed my galley seat that the entire area under the box where the pedestal originally was (about 2'x2') is 3/4" plywood even though the rest of the deck is 1/2" balsa core, AND it has about 1 layer of glass on the bottom and 2 layers on the top AND it's laying on top of TWO stringers that are about 1' apart! Good Luck, Denny

[Islandtrader]

I guess I did not explain my self very well.

The floor will be attached on all 4 sides.

The hull side will be bonded to the cleat with epoxy and then will be fiberglassed taped to the hull and floor.

The front will be bonded to the cleat and taped to the floor.

The center part will be bonded and taped to the riser and the right side of the floor (port side) and left side (starboard)of the floor will be bonded and taped together by the wider floor brace.

The back part rest on a bulkhead and will get the same treatment.

Whew I hope that is clear. One thing my wife says is that I over engineer everything. So attaching the floor is a big concern

[Bushwacker]

. . One thing my wife says is that I over engineer everything. So attaching the floor is a big concern

When it comes to mounting a pedestal seat, those things can't be too solid! I suspect Connor would agree!
Sounds like that panel will be well secured!
Denny

[cdavisdb]

VERY MUCH AGREE!!!

I'm scratching my head now trying to figure out how to do a permanent repair that will be strong enough. When mine broke, it split a 3/4 inch teak plank, broke a mounting screw and pulled a few more out of the fiberglass deck, not to mention what happened to the pedestal. Amazing what you can jury rig with enough screws, teak scraps and duct tape.

All that is going to wait a few months. The boat is finally cleaned repacked and put away. I don't even what to look at it for a month or so, much less work on it.

[Islandtrader]

Well the time was coming when I needed to get my power plant together. Placement of batteries, blower, scupper holes and the such dictated that I make a decision.

Besides this will give me real motivation to get the rest done and get out and run this puppy.

Mercury had a real good deal going so this is what I ordered up and should get it installed by the first of the year.



STROKER





It should make the 21 Cruise nicely.

[Bushwacker]

That should do it! Is that an EFI version?

[floorboy]

NICE!!!!! pm sent