Caulking Planking Rubbing Strips

1, Clean sawdust out of the planking seams with a small brush.

2. Use a caulking iron or a caulking wheel to press the cotton hard into the planking seams. This work Is very important to achieve a watertight boat

3 The best cotton for caulking is the twisted type that often comes like a rope with several strands which must be separated to fit into the seam,

  1. Follow the procedure shown for caulking, painting and applying mastic in the seam.
  2. Nail on the rubbing strip (wormshoe; on the keel and the protection strips on the stem as shown.
  3. Nail on the chine rubbing strip.

4x50

spaced 250

Tarpaper or bitumastic + flyscreen

Tarpaper or bitumastic + flyscreen

4x50

spaced 250

Rubbing Strips For Boats

Fill the seam with mastic Below waterline: Black-varnish + chalk putty.

  1. Press the cotton hard into the seam with the caulking iron or caulking wheel
  2. Brush thinned paint in seams over the waterllne. Use black-varnish below.

Fill the seam with mastic Below waterline: Black-varnish + chalk putty.

Fix a plank with top edge 80 below chine corner. Check that it is horizontal with a spirit level. The string rests on top of this plank.

Fix a plank with top edge 80 below chine corner. Check that it is horizontal with a spirit level. The string rests on top of this plank.

Paint For Cotton Caulk Boat

Fix a plank with the lower edge at the waterline mark at the stem, Brace it level. The string rests on the lower edge of this plank.

Move the string in and out on the planks so that it touches various places from forward to aft on the boat. Mark off. With a flexible batten connect the points and scribe with a hacksaw blade a clear line on the planking.

Fix a plank with the lower edge at the waterline mark at the stem, Brace it level. The string rests on the lower edge of this plank.

  1. Remove the boat from the building jig, but keep the cross braces until the rail is complete.
  2. Clamp on the outside rail batten and nail the sheerplank to it.
  3. Bolt the deckbeam to the forward frame and notch for the centerplank into the stem and the deckbeam.
  4. Clamp on the inside sheerbatten and nail it to the frames. Bevel for the covering board.
  5. Saw the covering board to shape and nail in place.
Fishing Boat

8x80

Deckbeam sawn from (6) 32 x 193

8x80

Deckbeam sawn from (6) 32 x 193

Covering board sawn from (18) 20 X 193

Covering board sawn from (18) 20 X 193

Install a shelf under the foredeck before nailing the foredeck in place.

Cut engine well beam and clamp it to the forward side of the aft intermediate beam. Cut the cleats, remove the beam and nail the cleats in place. Bolt the beam to the frame. Nail the bottom of the engine well then the sides and finally the deck which also serves as a seat for the operator.

20 x 193

20 x 193

What The Purpose Wormshoe
SECTION OF ENGINE WELL LOOKING FORWARD
  1. The simplest and cheapest Is to have no floorboards except in the bow because of the deep V - bottom .
  2. The next option is to have floorboards between the bottom battens.
  3. The most expensive solution is to have floorboards level with the top of the bottom frames, creating a flush floor
  4. After painting, fit buoyancy blocks as shown under the covering board in the centre two compartments and under the aft deck. The thwart forward Is for crew seats and for fitting a mast.

4 Two buoyancy blocks fitted under aft deck

4 Two buoyancy blocks fitted under aft deck

Caulking Floorboard

5x75 THWART

Buoyancy block 65 x 170 x 240 between frames

5x75 THWART

35x44

20x93 Gap = 10 between planks i ,

35x44

FLOORBOARDS BETWEEN BOTTOM BATTENS

Buoyancy block 65 x 170 x 240 between frames

FLOORBOARDS BETWEEN BOTTOM BATTENS

Prevented from moving sidewards by frames

16x145 removable

2 nails hold block

BUOYANCY

Prevented from moving sidewards by frames

44 x 44 sits on top of bottom batten

FLOORBOARDS FORWARD ARE REQUIRED

2 nails hold block

Caulking Floorboard

44 x 44 between frames, two on each side of centerline

15X68X300 notched to half depth of beam

BUOYANCY

44 x 44 between frames, two on each side of centerline

15X68X300 notched to half depth of beam

FLOORBOARDS LEVEL WITH TOP OF FRAMES Floorboards divided at centerline

1. PLYWOOD

All plywood for exterior use is glued with the some phenolic glue. It carries the mark WBP = water boil proof.

The durability of plywood is entirely dependent on the species of wood used in the veneers. Often the manufacturer saves money by having a good but thin surface veneer, but species with low rot resistance in the core veneers.

The difference between UWBP Exterior" plywood and "Marine plywood" is in the species of timber accepted for the veneers and the thickness and number of layers. "Marine plywood" should have a minimum of 5 layers in plywood between 6 and 9 mm thickness. More layers give more equal strength along the sheet and across the sheet. The thickness of the layers should be :

Outer layers: Minimum 1,4 mm Inner layers: Maximum 2.5 mm

Unless the veneers have been treated against rot at the factory, the durability of the plywood is dependent on the type of wood used. The following list of species for marine use has been prepared by Lloyds in England:

Common name

Natural durability

Agba

Gedu Nohor

Guarea

Idigbo

African Mahogany

Makore

Light Red Meranddl Light Red Seraya Sapele Utile

Durable

Moderately durable

Durable

Durable

Moderately durable Very durable Moderately durable Moderately durable Moderately durable Moderately durable Durable

Douglas fir and Gaboon/Okoume are acceptable provided they are given preservative treatment at the factory. Gaboon/Okoume has very low natural durability.

In plywood construction it is important to seal all edges with epoxy glue. Especially where the deck overlaps the side there are problems of rot if the edge is not well sealed before fastening the sheer batten.

2. TIMBER

The timber for the plywood boat must first of all be suitable for gluing. Generally the heavier type A timber as described on page 18 does not give as good a glue bond as the lighter timber. An exception to this is Iroko and Kapur. Generally type B timber is therefore used in plywood boat construction. The keel and keel-shoe should preferably be of a heavier and harder timber.

3. GLUE

There are two types of glue with a proven record as waterproof glue: Epoxy and Phenol Resorcinol.

Epoxy has a better gap filling ability which means that less clamping pressure is required to achieve a good bond. However, epoxy presents a greater health risk. Contact with the skin should be avoided as some people develop a skin rash after having used epoxy over a period. The hardener powder of phenol resorcinol is toxic and should be handled with care.

The following rules are important for a good glue bond.

  1. The correct measuring of quantities of resin and hardener and proper mixing is very important for a good bond. Use a postal scale if necessary and follow the instructions on the tin carefully. Glue is expensive so do not spoil the result by careless mixing.
  2. The lids of the glue tins should be put on properly and the tins stored in a cool place 5-20 °C. Storage time will then be 1 -2 years. In a hot climate the "shelf life" of the glue is much reduced.
  3. Plane the timber to equal thickness with a machine planer. Although epoxy has a gap filling property, the surfaces should be fairly even, d) Freshen up the wood surface. If time from planing is more than 48 hours before gluing, the wood should be freshened up with sandpaper followed by brushing off the dust. This gives fresh wood directly in contact with the glue.
  4. Use timber of correct moisture content. Wet timber will not glue well and too dry timber puts high stress on the glueline when swelling takes place after the boat is put into service,

4, FASTENINGS

The purpose of the fastenings is to provide sufficient pressure until the glue sets. The fastening itself will take no load as long as the glueline is intact. Only in an emergency with giue failure might the fastening provide some additional safely. Use screws only where the bend in the plywood is too extreme.

Nails

The best type of fastening is the annular ringed or barbed bronze nail. The nails also carry the name "Gripfast". For the 9 mm plywood used in these boats the following size is recommended: Diameter = 2 mm (14 SWG), Length = 25 mm (1 in),

If these nails are not available, hot dipped gdlvanized nails can be used. The nails should have a small head so that they can be countersunk below the surface of the plywood and the hole plugged with a filler to avoid any surface corrosion. For 9 mm plywood the dimension should be: Diameter = 2.65 (12 SWG), Length = 30 mm

The length of these nails means that they have to be set at an angle in the 25 mm battens to avoid splitting the inside surface.

Round wire nail, countersunk head Barbed bronze na , , .

hot dipped galvanized

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How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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