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Deck Fitting Musings
By:Mike Allen
Date: 2/8/1999, 5:10 pm

This is in reaction to some recent posts, but also meandering beyond:

A) A few deck fitting ideas: 1) Recessed Type

-premise- shallow,drainable, & strong

Before glassing, drill 3/4" hole @ fitting location. Chamfer edges.

From below, take a typical padeye fitting (or brass,whatever - to padeye

shape) and push up from BELOW. Take any flat scap with notch cut in

the ends for the padeye ends & glue from below. (I've left out glass

sequencing for brevity). You now have low or flush profile fitting,

only deck thickness deep for drainage. If tied off (wire,roving) below scrap from mounting hole to mounting hole, it would be as strong as you

wish to make the backup. 2)Goofy - but opens up many possibilities

Funny idea, but why not just put two holes next to each other and thread

thru deck? Back it up with a pc of scrap w/ a groove from hole to hole.

Holes slant toward ea. other. After rigging but before you hit the water, fill up the grooves with silicone. Sorta like sewing lines

in the deck!

An extension is to use clear plastic tubing below the glass on the deck

and glassed over. A couple of extra pcs of glass over for strength and

voila. Or 3/8" copper pipe angle cut or 3/8" brass box sections like

from a good model store. 3)Webbing:

Some of the webbing ideas so far maybe could be stronger and more

minimal so:

After stripping (before glassing), make a 1" long by 1/8" slot BETWEEN

2 strips through the deck at the fitting location. Either leave as is

or make this into a groove (for concealment if kayak unrigged for extended periods). Glass outside only. Take 5"(inches) of 1/2"

webbing, fold in half, thread thru slot leaving a 3/8"diam loop. Flip

over,spread out webbing ends, glue to underside of deck and then glass

interior. You gotta like this guy - even not recessed it's minimal

and very strong! Match webbing color to rigging color - the fitting

is invisible from 2' away. Total extra weight - prob 5 nanograms! Or if

you weigh the wood you cut out and balance with the webbing you put in

it ends up weighing nothing! (joke)

(A variation is to cut a wedge shaped plug from below, wrap wedge with webbing, jam plug back in hole and glass from below.)

Another thought - if the slot is chamfered, why not use a 1/2" x 5" sheet of metal (copper, brass or whatever) formed to the chamfer profile

- lots of possibilities here.

e.g. what about sacrificial hardwood, drilled for lines, beds in chamfer

mounted w/ t-nuts from below? - I know - nutty!!

Digression

It occur(ed)s to me that a combination of the stitch concept with the

webbing approach can apply to two other areas of considerable discussion

and concern: B) Flush Hatch Musings:

- use typical flush hatch construction process:

strip deck, cut hatch, make flange in deck.

1) Just "sew" it on using A2 approach. Back up all holes so no compartment leakage. Aesthetically pleasing and stronger than hzll! Water in hole issue maybe.

2)Install alternate webbing loops in deck and in hatch (A3 method) all

around the hatch from deck to hatch to deck etc., and just stitch it

in place with a bungee or rope. This would be 10X more secure than any

method I've seen yet. Pretty and minimal too.

3) Chamfer a groove between hatch and deck. Alternate loops of a hard material (your choice). Run a pin through to lock in place. This approach could also be used upside down (internally) for a totally

concealed locking system.

4) I guess the previous idea is just a variation of a removable pin piano

hinge. This could also be used. Mount flanges as you prefer, vertically

or horizontally so that the hinge axis is either above deck/hatch split,

in deck/hatch spit, or below (long pins). Use metal hinge but prob best

are heavy duty plastic as used on large scale radio controlled model airplane control surfaces. The simplest would probably be the hinge axis in the hatch/deck seam.

A major aspect of B123 are that the are structural.

5)Wierd but worth considering:

After hatch cut out, run cove edge around hatch edge and aroung deck edge. Take a pc of 1/16" wire and attach to end of 1/4" rope (as long

as the perimeter of the hatch). Place hatch in place and put a 1/4" notch somewhere along the seam line. Thread in the rope by pulling on

the wire, and pull the wire all around the seam. To remove , pull the

wire back thru the notch. Downside - you must use vented bulkheads (easy) - hull flexture could compromise - 0ne continuous rope is

probably too much, but the idea is such a hoot. Try using bungee rope

pulled taut, when you let go, it swells up to bind. Or 1/4" surgical

tubing as it probably thins out more and seals better.

6)Wierdo continued further:

Take a small bicycle wheel inner tube(I assume 1" diam. x-sect).

Place on uncut deck. Draw any shape hatch profile whose perimeter

matches that of the ctrline circumference of the tube. Flip deck.

On underside glue 1" thick ethafoam ( or minicell or polyurethane etc.)

to 2" wider all around than the hatch profile. Flip deck back. Cut out

hatch - cutting ethafoam at the same time. Apply flange to u/s of deck

ethafoam. Route out 1" cove in hatch ethafoam (if too weak, sandwich

it like deck). Route 1" cove in deck ethafoam. File 1/4" notch in

seam line anywhere for valve. Deflate tube, mount it around hatch, put

hatch in place w/ valve thru notch. Blow up tube! If lung pressure is

3psi or more it may be enough to be quite secure. Or use water pump

backwards (air). Maybe slight cove offsets to give more sealing

pressure(?). This one is well nigh invisible too.

7)Another:

-assumes hatch w/ flange

Under flange, attach 2" wide strip of 1" ethafoam all around and flush

with the opening. Sand or rasp this ethafoam edge back 45 deg. ( could

have used 45 deg. to start). Take hatch, put in place, run a pencil

from below all around the flange marking its location on the hatch.

Take off hatch and glue on your favourite ( slightly larger than

hatch) airbag to the bottom of the hatch except beyond the pencil

lines. Poke up valve somewhere thru hatch (use pretty fitting or

minimal). Put hatch in place, blow up airbag - its stuck - and you won't

sink either!

As an aside, here is a simple, quick, brainless way to get a perfect hatch seal that accounts for major inaccuracies:

-assumes hatch, flange but no seal yet installed Lightly hot glue 6 or so 2" strips on hatch sticking radially out across perimeter so when you place it on deck it aligns perfectly flush. Remove hatch and put a layer of saran wrap (or other silicone release) on the mating surface of the hatch (not deck). Run a generous bead of silicone sealant around the deck flange. Mush on hatch and gently(!) clamp in place to its previous perfect location. Clean up excess (wet finger or other tool). Go paddle your beater. Next day, pop off the hatch. You simply won't believe the fit!

Now this has taken 3x longer than I expected and some of these ideas logically extend to end loops. But I'm at work and gotta go! As previously stated these are untested ideas only- I've yet to start anything. See ya.

Messages In This Thread

Deck Fitting Musings
Mike Allen -- 2/8/1999, 5:10 pm
Re: More readable?
Mike Allen -- 2/8/1999, 5:51 pm
More Fitting Musing
Mike Allen -- 2/9/1999, 4:52 pm