Although building a motorboat with plywood sheathing and a traditional hull design - with a transverse frame and longitudinal beams along the grooves on the keel, chine and along the upper edge of the side - is not too difficult, it still requires certain skills, care and precision when working. First, the builder will have to mark the outlines of the frames in full size - break out the plaza, then assemble frame frames or strong assembly patterns along the plaza, finally build a strong slipway, accurately align on it and align the entire transverse set, and then the longitudinal set (keel, stringers, fenders), remove the fender from the slats, and only after this can you begin to adjust the outer skin sheets and install them in place. In general, the work turns out to be quite labor-intensive; it is required to occupy any assembly space for a long time, which can pose a problem for a city dweller.
Meanwhile, there is a simpler technological method for assembling small plywood boats, which does not require the manufacture of a slipway and a large number of transverse frames or patterns. This method using paper clips copper wire and fiberglass tapes have been successfully tested by our amateur shipbuilders in the construction of small rowing and sailing boats (see, for example, the description of the construction of a yacht tug in or a “Crab” boat in). We propose to use the same method to build a four-seater motor boat.
Basic data
The difference between this method and the traditional one is that the contours of the boat’s hull are obtained during its assembly thanks to pre-cut sheets of sheathing, and the assembly of the hull consists of connecting these sheets along the edges. In this case, there is no need to build a slipway - a flat floor surface or outdoor area is sufficient. The work itself no longer requires great skill. The time the housing remains indoors during the assembly process can be reduced to a minimum. All blanks and parts can be stored in the apartment “in flat view"and take the three-dimensional shape of the vessel literally in 3-4 working days.
"Som" - small cabin motorboat with moderately keeled bottom contours, which can be used for fishing trips or for weekend tourism. “Faceted” body contours, composed of long sheets outer plating and coamings of the deckhouse, make it possible to apply the above-mentioned stitching method and at the same time ensure sufficient rigidity of the practically non-studded hull. The hull's shape and strength are given by the cabin bulkhead, just one frame, transom, and the structure of the aft sofa and engine niche. The bottom sheets, after the skin is assembled, are supported by four stringer slats and intermediate floras - supports for the flooring. This is necessary so that when sailing in rough seas, the plywood bottom does not begin to act like a thin membrane: with constant repeated bending of the skin plates, the fiberglass joints in the grooves - along the keel and chine - may, if not collapse, then lose their tightness.
For cladding, it is advisable to purchase five-layer (aviation) waterproof plywood 6 mm thick. You will need 14-15 sheets of it standard sizes 1525Х1525 mm.
The work begins by connecting all sheet blanks to the required length. The best way- glue the sheet together using epoxy glue (or another waterproof glue) “on the mustache”; necessary recommendations can be found in the book “15 boat projects for amateur construction” or, for example, in the article about building the “Flying Fish” windsurfer, published in. Then, on the inside of each sheet, straight, mutually perpendicular lines are applied to mark the contours according to the sketches provided; these lines will also be necessary for control during subsequent assembly of the housing. Smooth curved edges can be drawn along the intended points using a thin flexible strip at least 3 m long.
The sheets are cut along the edges with a fine-toothed hacksaw and planed with a plane so that when stitching, the edges are joined with as little gap as possible; the planes of the ends of the plywood have to be cut “at an angle” (as shipbuilders say, remove the filler from the edges).
From the remains of the plywood sheets, parts of the transom, bulkhead and frame frame are cut out. When assembling the body, these nodes play the role of transverse patterns.
Assembly begins by connecting a pair of bottom skin sheets along the keel groove. Departing from the edge of the keel by 6 mm, a line is drawn on both sheets, which will serve as a center line for drilling holes for wire clips. First, the edges of the sheets to be joined are fastened after 75 mm. At the bow end, where the mating edges form the stem line, it is better to reduce the pitch between the clips. In one of the joined edges, holes can be drilled along the entire length at once, and in the edge of the second sheet, it is better to drill holes in place - sequentially, in sections 500-600 mm long, otherwise when the edges are bent along a curved line, the distances between the holes may turn out to be mismatched.
Paper clips are made of copper wire with a diameter of about 2 mm; Having cut pieces of wire about 40 mm long and bent them in the form of deep brackets, the paper clips are inserted with inside sheathing into the holes and from the outside, twist the ends with pliers. At first, there is no need to try to bring the edges of the joined sheets together too tightly - this will need to be done immediately before gluing the grooves with fiberglass.
It is better to start installing the clips from the stern, and when the clips stand at a groove length of 1-1.5 m, it is recommended to temporarily install the transom in place - it will help give the bottom the desired deadrise and when further work obtain the correct longitudinal contour of the keel. Later it will also be possible to temporarily “attach” the cabin bulkhead and the frame frame in the bow of the boat. Having gone through the entire keel groove in this way, you need to make sure that the contours are correct and the edges of the plywood fit tightly, and tighten the wire in places where there is an excessive gap.
Then both sheets of side plating are put in place; they are grabbed to the exposed set using clamps, a strong cord and nails, and then their edges are connected to the edges of the bottom sheets along the chine, working from the transom in sections of 500-600 mm alternately on both sides.
After tightening the brackets, the temporarily installed transverse set can be removed, having previously marked on the bottom skin the position of the floors, and on the floors, the locations of the cutouts for the passage of the longitudinal slats - stringers. The stringer blanks are put in place using glue and nails driven through the sheathing into checkerboard pattern for a reliable fit of the slats to the sheathing along the entire surface. In the nose, where the bend is large, it is better to install rivets or screws.
Staples are more of a mounting element than a fastening of the skin sheets for the entire subsequent operation of the boat. The main strength of the joints is provided by fiberglass, which is formed using thin fiberglass tapes glued with epoxy glue in several layers on both sides of the joint. In order to get a dense layer of fiberglass without air bubbles and peeling from the plywood, it is necessary to carefully embed the wire of the staples into the wood, which protrudes from the inside of the body in the form of “bridges” above the groove. This can be done using a hammer and chisel with a rounded cutting part or another similar tool; in this case, the seam receives additional compaction.
Gluing the joints begins from the inside of the skin. Before gluing the first fiberglass strip, it is useful to limit the width of the strip lubricated with adhesive by placing adhesive tape on both sides of the groove. A pre-prepared binder (epoxy resin - 100 parts by weight; polyethylene polyamine - 10 parts by weight; dibutyl phthalate - 15 parts by weight, or other components according to the instructions for using the resin available to boat builders) is applied with a brush, then a dry tape of fiberglass In this case, the tape is simply rolled out, but not stretched. From the outside, the fiberglass fabric is tapped with a brush dipped in a binder until the tape is evenly impregnated - it becomes transparent. Air bubbles must be carefully removed, otherwise they will subsequently cause plastic delamination and water filtration.
It is advisable to use factory-made tape - it is widely used for insulation work. You just need to check that the fiberglass fabric is not saturated with lubricant; if she has high humidity, you will have to heat the tape in the oven of a gas stove.
It is enough to apply three layers of tape on both sides of the sheathing to obtain a connection equal to the strength of the plywood. If, when applying the first layer, the binder protrudes from the outside of the joint, this indicates good impregnation of the joint. The layers need to be applied, slightly moving them towards the board in relation to the previous one, so that an overlap of 10-15 mm is obtained along the edge. If you have to cut the fiberglass strips yourself, you can make the top layers wider in advance. The ends of individual pieces of tape should also be overlapped.
When the fiberglass has gelled, you can remove the restrictive adhesive tape and leave the body for a day until the joint has completely hardened.
The next stage of construction is the installation in place (using glue and screws) of the transverse set of the hull and the deckhouse coamings, which are connected to the upper edges of the side plating using paper clips in exactly the same way as has already been described.
The builder is given the opportunity to choose one of two options for designing the bow end of the boat above the waterline. You can either sew both edges of the sides with paper clips and not install any stem, or make a stem from a board, as shown in the drawing, and attach the bow edges of the sides to it with glue and screws. It all depends on whether the builder likes the blunt bow of the boat or whether he prefers to make it sharp.
Before gluing the grooves from the outside, you need to bite off the protruding twists of wire with pliers as close as possible to the surface of the sheathing, and saw down the remaining ends of the wire flush with the plywood. Then a limiting adhesive tape is laid along the groove and fiberglass is glued as described above.
Once all the longitudinal connections have been completed, all that remains is to mount the entire structure inside the wheelhouse and cockpit, and then draw in place and staple the roof of the cabin made of plywood 5-6 mm thick. If there are difficulties with the bending of the roof, cut from one solid sheet, it can be cut along the DP and connected to a longitudinal rail - karlengs, which reinforces the roof of the cabin.
It is recommended to cover the outside of the bottom with a continuous layer of fiberglass so that its edges extend to the sides slightly above the cheekbone. When processing all surfaces covered with fiberglass, it should be remembered that the resin layer must not be allowed to be removed and the fiberglass fabric exposed: in this case, the glass filaments will begin to filter water through the capillary channels between the fibers and the edges of the plywood in the joints covered with plastic on both sides will soon begin to rot. Therefore, such places should be carefully filled with epoxy putty.
When finalizing the boat, one should not forget about such details as the layouts that form the upper edges of the coamings in the area of the cockpit, transom and recess bulkhead; beads on the sides; metal strip on the stem (it is advisable to extend it along the entire length of the keel). In addition to decorative purposes, these parts protect the body from abrasion and impact, and cover the edges of the plywood from the penetration of moisture between the layers.
| Basic data of the Som motorboat: | |
|---|---|
| Maximum length, m | 4,40 |
| Maximum width, m | 1,65 |
| Side height at midship, m | 0,80 |
| Empty motorboat weight, kg | 180 |
| Height in cabin, m | 1,04 |
| Passenger capacity, persons | 4 |
| Recommended power outboard motor, l. With. | 8~25 |
Although building a motorboat with plywood sheathing and a traditional hull design - with a transverse frame and longitudinal bars along the grooves on the keel, chine and along the upper edge of the side - is not too difficult, it still requires certain skills, care and precision when working. First, the builder will have to mark the outlines of the frames in full size - break out the plaza, then assemble frame frames or strong assembly patterns along the plaza, finally - build a strong slipway, accurately align on it and align the entire transverse set, and then the longitudinal set (keel, stringers, fenders), remove the fender from the slats, and only after this can you begin to adjust the outer skin sheets and install them in place. In general, the work turns out to be quite labor-intensive; it is required to occupy any assembly space for a long time, which can pose a problem for a city dweller.
Meanwhile, there is a simpler technological method for assembling small plywood boats, which does not require the manufacture of a slipway and a large number of transverse frames or patterns - building a boat using the “sew and glue” method. This method, using copper wire clips and fiberglass tapes, has been successfully tested by our amateur shipbuilders in the construction of small rowing and sailing boats (see, for example, the description of the construction of a yacht boat) or the “Crab” boat). We suggest using the same “sew and glue” method to build a four-seater motor boat.
The difference between this method of building boats using the “sew and glue” method from the traditional one is that the contours of the boat hull are obtained during its assembly thanks to pre-cut sheets of skin, and the assembly of the hull consists of joining these sheets along the edges. In this case, there is no need to build a slipway - a flat floor surface or outdoor area is sufficient. The work itself no longer requires great skill. The time the housing remains indoors during the assembly process can be reduced to a minimum. All blanks and parts can be stored in the apartment in a “flat form” and take the three-dimensional shape of the vessel in literally 3-4 working days.
"Som" - a small cabin motorboat with moderately keeled bottom contours, which can be used for fishing trips or for weekend tourism. “Faceted” hull contours, made up of long sheets of outer plating and deckhouse coamings, make it possible to apply the above-mentioned stitching method and at the same time ensure sufficient rigidity of a practically non-studded hull. The hull's shape and strength are given by the cabin bulkhead, just one frame, transom, and the structure of the aft sofa and engine niche. The bottom sheets, after the skin is assembled, are supported by four stringer slats and intermediate floor supports for the flooring. This is necessary so that when sailing in rough seas, the plywood bottom does not begin to act like a thin membrane: with constant repeated bending of the skin plates, the fiberglass joints along the grooves - along the keel and chine - may, if not collapse, then lose their tightness.
increase
1 - internal lining of coaming and recess, δ=6; 2 - facing strip, 15x25, oak; 3 - rail 25x25; 4 - 25x30 rail for fastening the steering seat; 5 - plexiglass, δ=5~6; 6 - breshtuk δ=20, pine; 7 - stem, δ=24; 8 - beam 16x60; 9 - support rail 25x30; 10 - rail 16x32; 11 - bed flooring, δ=4~6; 12 - floor 20x135; 13 - bottom stringer, 20x25; 14 - flooring of the engine niche; 15 - rail 16x55; 16 - knitsa, δ=6; 17 - rail 16x32; 18 - 16x55 beams, glued together from nine 16x6 slats; 19 - door post, 16x55; 20 - transom trim 32x32; 21 - transom, δ=8~12; 22 - transom bracket, δ=6; 23 - under-engine board, 160x32; 24 - rail 25x25; 25 - collar 25x25, oak; 26 - rail 20x25; 27 - locker bulkhead, δ=4~6; 28 - wheelhouse coaming, δ=6; 29 - side plating sheet; 30 - bottom plating sheet; 31 - lining edge, 16x75.
increase
For cladding, it is advisable to purchase five-layer (aviation) waterproof plywood 6 mm thick. You will need 14-15 sheets of standard sizes 1525x1525 mm.
The work begins by connecting all sheet blanks to the required length. The best way is to glue the sheet with epoxy glue (or other waterproof glue) “on the mustache”; the necessary recommendations can be found in the book or, for example, in the article on the construction of the “Flying Fish” windsurfer, published in “KiYa” No. 82. Then, on the inside of each sheet, straight, mutually perpendicular lines are applied to mark the contours according to the sketches provided; these lines will also be necessary for control during subsequent assembly of the housing. Smooth curved edges can be drawn along the intended points using a thin flexible strip at least 3 m long.
The sheets are cut along the edges with a fine-tooth hacksaw and planed with a plane so that when stitching, the edges are joined with as little gap as possible; the planes of the ends of the plywood have to be cut “at an angle” (as shipbuilders say, remove the filler from the edges).
From the remains of the plywood sheets, parts of the transom, bulkhead and frame frame are cut out. When assembling the body, these nodes play the role of transverse patterns.
Assembly begins by connecting a pair of bottom skin sheets along the keel groove. Departing from the edge of the keel by 6 mm, a line is drawn on both sheets, which will serve as a center line for drilling holes for wire clips. First, the edges of the sheets to be joined are fastened after 75 mm. At the bow end, where the mating edges form the stem line, it is better to reduce the pitch between the clips. In one of the joined edges, holes can be drilled along the entire length at once, and in the edge of the second sheet, it is better to drill holes in place - sequentially, in sections 500-600 mm long, otherwise when the edges are bent along a curved line, the distances between the holes may turn out to be mismatched.
Paper clips are made of copper wire with a diameter of about 2 mm; Having cut pieces of wire about 40 mm long and bent them in the form of deep brackets, paper clips are inserted into the holes from the inside of the casing and the ends are twisted from the outside with pliers. At first, there is no need to try to bring the edges of the joined sheets together too tightly - this will need to be done immediately before gluing the grooves with fiberglass.
a - wire settling; b - the connection is ready for pasting with plastic; c - gluing the connection from the inside.
It is better to start installing the clips from the stern, and when the clips stand at a groove length of 1-1.5 m, it is recommended to temporarily install the transom in place - it will help give the bottom the desired deadrise and, during further work, obtain the correct longitudinal contour of the keel. Later it will also be possible to temporarily “attach” the cabin bulkhead and the frame frame in the bow of the boat. Having gone through the entire keel groove in this way, you need to make sure that the contours are correct and the edges of the plywood fit tightly, and tighten the wire in places where there is an excessive gap.
Then both sheets of side plating are put in place; they are grabbed to the exposed set using clamps, a strong cord and nails, and then their edges are connected to the edges of the bottom sheets along the chine, working from the transom in sections of 500-600 mm alternately on both sides.
After tightening the brackets, the temporarily installed transverse set can be removed, having previously marked on the bottom skin the position of the floors, and on the floors, the locations of the cutouts for the passage of the longitudinal slats - stringers. The stringer blanks are placed in place using glue and nails driven through the sheathing in a checkerboard pattern to securely adhere the strip to the sheathing along the entire surface. In the nose, where the bend is large, it is better to install rivets or screws.
Staples are more of a mounting element than a fastening of the skin sheets for the entire subsequent operation of the boat. The main strength of the joints is provided by fiberglass, which is formed using thin fiberglass tapes glued with epoxy glue in several layers on both sides of the joint. In order to get a dense layer of fiberglass without air bubbles and peeling from the plywood, it is necessary to carefully embed the wire of the staples into the wood, which protrudes from the inside of the body in the form of “bridges” above the groove. This can be done using a hammer and chisel with a rounded cutting part or another similar tool; in this case, the seam receives additional compaction.
Gluing the joints begins from the inside of the skin. Before gluing the first fiberglass strip, it is useful to limit the width of the strip lubricated with adhesive by placing adhesive tape on both sides of the groove. A pre-prepared binder (epoxy resin - 100 parts by weight; polyethylene polyamine - 10 parts by weight; dibutyl phthalate - 15 parts by weight, or other components according to the instructions for using the resin available to boat builders) is applied with a brush, then a dry tape of fiberglass In this case, the tape is simply rolled out, but not stretched. From the outside, the fiberglass fabric is tapped with a brush dipped in a binder until the tape is evenly impregnated - it becomes transparent. Air bubbles must be carefully removed, otherwise they will subsequently cause plastic delamination and water filtration.
It is advisable to use factory-made tape - it is widely used for insulation work. You just need to check that the fiberglass fabric is not saturated with lubricant; if it has high humidity, you will have to heat the tape in the oven of a gas stove.
It is enough to apply three layers of tape on both sides of the sheathing to obtain a connection equal to the strength of the plywood. If, when applying the first layer, the binder protrudes from the outside of the joint, this indicates good impregnation of the joint. The layers need to be applied, slightly moving them towards the board in relation to the previous one, so that an overlap of 10-15 mm is obtained along the edge. If you have to cut the fiberglass strips yourself, you can make the top layers wider in advance. The ends of individual pieces of tape should also be overlapped.
When the fiberglass has gelled, you can remove the restrictive adhesive tape and leave the body for a day until the joint has completely hardened.
The next stage of construction is the installation in place (with glue and screws) of the transverse set of the hull and the deckhouse coamings, which are connected to the upper edges of the side plating with staples in exactly the same way as has already been described.
The builder is given the opportunity to choose one of two options for designing the bow end of the boat above the waterline. You can either sew both edges of the sides with paper clips and not install any stem, or make a stem from a board, as shown in the drawing, and attach the bow edges of the sides to it with glue and screws. It all depends on whether the builder likes the blunt bow of the boat or whether he prefers to make it sharp.
Before gluing the grooves from the outside, you need to bite off the protruding twists of wire with pliers as close as possible to the surface of the sheathing, and file the remaining ends of the wire flush with the plywood. Then a limiting adhesive tape is laid along the groove and fiberglass is glued as described above.
Once all the longitudinal connections have been completed, all that remains is to mount the entire structure inside the wheelhouse and cockpit, and then draw in place and staple the roof of the cabin made of plywood 5-6 mm thick. If there are difficulties with the bending of the roof, cut from one solid sheet, it can be cut along the DP and connected to a longitudinal rail - karlengs, which reinforces the roof of the cabin.
It is recommended to cover the outside of the bottom with a continuous layer of fiberglass so that its edges extend to the sides slightly above the cheekbone. When processing all surfaces covered with fiberglass, it should be remembered that the resin layer must not be allowed to be removed and the fiberglass fabric exposed: in this case, the glass filaments will begin to filter water through the capillary channels between the fibers and the edges of the plywood in the joints covered with plastic on both sides will soon begin to rot. Therefore, such places should be carefully filled with epoxy putty.
When finalizing the boat, one should not forget about such details as the layouts that form the upper edges of the coamings in the area of the cockpit, transom and recess bulkhead; beads on the sides; metal strip on the stem (it is advisable to extend it along the entire length of the keel). In addition to decorative purposes, these parts protect the body from abrasion and impact, and cover the edges of the plywood from the penetration of moisture between the layers.
D. Antonov, “Boats and Yachts”, No. 83.
For cladding, it is advisable to purchase five-layer (aviation) waterproof plywood 6 mm thick. You will need 14-15 sheets of standard sizes 1525x1525 mm.
The work begins by connecting all sheet blanks to the required length. The best way is to glue the sheet using epoxy glue (or other waterproof glue) “on the mustache”; the necessary recommendations can be found in the book “15 boat projects for amateur construction” or, for example, in the article on the construction of the “Flying Fish” windsurfer, published in “KYa” No. 82. Then, on the inside of each sheet, straight, mutually perpendicular lines are applied to mark the contours according to the sketches provided; these lines will also be necessary for control during subsequent assembly of the housing. Smooth curved edges can be drawn along the intended points using a thin flexible strip at least 3 m long.
The sheets are cut along the edges with a fine-tooth hacksaw and planed with a plane so that when stitching, the edges are joined with as little gap as possible; the planes of the ends of the plywood have to be cut “at an angle” (as shipbuilders say, remove the filler from the edges).
From the remains of the plywood sheets, parts of the transom, bulkhead and frame frame are cut out. When assembling the body, these nodes play the role of transverse patterns.
Assembly begins by connecting a pair of bottom skin sheets along the keel groove. Departing from the edge of the keel by 6 mm, a line is drawn on both sheets, which will serve as a center line for drilling holes for wire clips. First, the edges of the sheets to be joined are fastened after 75 mm. At the bow end, where the mating edges form the stem line, it is better to reduce the pitch between the clips. In one of the joined edges, holes can be drilled along the entire length at once, and in the edge of the second sheet, it is better to drill holes in place - sequentially, in sections 500-600 mm long, otherwise when the edges are bent along a curved line, the distances between the holes may turn out to be mismatched.
Paper clips are made of copper wire with a diameter of about 2 mm; Having cut pieces of wire about 40 mm long and bent them in the form of deep brackets, paper clips are inserted into the holes from the inside of the casing and the ends are twisted from the outside with pliers. At first, there is no need to try to bring the edges of the joined sheets together too tightly - this will need to be done immediately before gluing the grooves with fiberglass.
It is best to start installing the clips from the stern, and when the clips stand at a groove length of 1-1.5 m, it is recommended to temporarily install the transom in place - it will help give the bottom the desired deadrise and, during further work, obtain the correct longitudinal contour of the keel. Later it will also be possible to temporarily “attach” the cabin bulkhead and the frame frame in the bow of the boat. Having gone through the entire keel groove in this way, you need to make sure that the contours are correct and the edges of the plywood fit tightly, and tighten the wire in places where there is an excessive gap.
Then both sheets of side plating are put in place; they are grabbed to the exposed set using clamps, a strong cord and nails, and then their edges are connected to the edges of the bottom sheets along the chine, working from the transom in sections of 500-600 mm alternately on both sides.
After tightening the brackets, the temporarily installed transverse set can be removed, having previously marked on the bottom skin the position of the floors, and on the floors, the locations of the cutouts for the passage of the longitudinal slats - stringers. The stringer blanks are placed in place using glue and nails driven through the sheathing in a checkerboard pattern to securely adhere the strip to the sheathing along the entire surface. In the nose, where the bend is large, it is better to install rivets or screws.
Staples are more of a mounting element than a fastening of the skin sheets for the entire subsequent operation of the boat. The main strength of the joints is provided by fiberglass, which is formed using thin* fiberglass tapes glued with epoxy glue in several layers on both sides of the joint. In order to get a dense layer of fiberglass without air bubbles and peeling from the plywood, it is necessary to carefully embed the wire of the staples into the wood, which protrudes from the inside of the body in the form of “bridges” above the groove. This can be done using a hammer and chisel with a rounded cutting part or another similar tool; in this case, the seam receives additional compaction.
Gluing the joints begins from the inside of the skin. Before gluing the first fiberglass strip, it is useful to limit the width of the strip lubricated with adhesive by placing adhesive tape on both sides of the groove. Pre-prepared binder Epoxy resin-100 wt. h.; polyethylenepolyamine-10 wt. h.; dibutyl phthalate-15 wt. h., or other components according to the instructions for using the resin available to boat builders) is applied with a brush, then a dry fiberglass tape is applied. In this case, the tape is simply rolled out, but not stretched. From the outside, the fiberglass fabric is tapped with a brush dipped in a binder until the tape is evenly impregnated - it becomes transparent. Air bubbles must be carefully removed, otherwise they will subsequently cause plastic delamination and water filtration.
It is advisable to use factory-made tape - it is widely used for insulation work. You just need to check that the fiberglass fabric is not saturated with lubricant; if it has high humidity, you will have to heat the tape in the oven of a gas stove.
It is enough to apply three layers of tape on both sides of the sheathing to obtain a connection equal to the strength of the plywood. If, when applying the first layer, the binder protrudes from the outside of the joint, this indicates good impregnation of the joint. The layers need to be applied, slightly moving them towards the board in relation to the previous one, so that an overlap of 10-15 mm is obtained along the edge. If you have to cut the fiberglass strips yourself, you can make the top layers wider in advance. The ends of individual pieces of tape should also be overlapped.
When the fiberglass has gelled, you can remove the restrictive adhesive tape and leave the body for a day until the joint has completely hardened.
The next stage of construction is the installation in place (with glue and screws) of the transverse set of the hull and the deckhouse coamings, which are connected to the upper edges of the side plating with staples in exactly the same way as has already been described.
The builder is given the opportunity to choose one of two options for designing the bow end of the boat above the waterline. You can either sew both edges of the sides with paper clips and not install any stem, or make a stem from a board, as shown in the drawing, and attach the bow edges of the sides to it with glue and screws. It all depends on whether the builder likes the blunt bow of the boat or whether he prefers to make it sharp.
Before gluing the grooves from the outside, you need to bite off the protruding twists of wire with pliers as close as possible to the surface of the sheathing, and file the remaining ends of the wire flush with the plywood.
Then a limiting adhesive tape is laid along the groove and fiberglass is glued as described above.
Once all the longitudinal connections have been completed, all that remains is to mount the entire structure inside the wheelhouse and cockpit, and then draw in place and staple the roof of the cabin made of plywood 5-6 mm thick. If there are difficulties with the bending of the roof, cut from one solid sheet, it can be cut along the DP and connected to a longitudinal rail - karlengs, which reinforces the roof of the cabin.
It is recommended to cover the outside of the bottom with a continuous layer of fiberglass so that its edges extend to the sides slightly above the cheekbone. When processing all surfaces covered with fiberglass, it should be remembered that the resin layer must not be allowed to be removed and the fiberglass fabric exposed: in this case, the glass filaments will begin to filter water through the capillary channels between the fibers and the edges of the plywood in the joints covered with plastic on both sides will soon begin to rot. Therefore, such places should be carefully filled with epoxy putty.
When finalizing the boat, one should not forget about such details as the layouts that form the upper edges of the coamings in the area of the cockpit, transom and recess bulkhead; beads on the sides; metal strip on the stem (it is advisable to extend it along the entire length of the keel). In addition to decorative purposes, these parts protect the body from abrasion and impact, and cover the edges of the plywood from the penetration of moisture between the layers.
D. Antonov, "Boats and Yachts", No. 83.
Instructions
First, decide on the construction technology. There are two main methods: in the first, a body kit is first made and covered with thin plywood. Then the finished body is covered with several layers of fiberglass. When using the second option, a matrix is made, in which the body is then glued.
The first option is suitable for those who build in a single copy. The disadvantage of this method is that the finished body requires quite labor-intensive processing. The second option requires the expenditure of material and time, but at the same time allows you to obtain a body with ideal surface, requiring only painting. This method is advisable to use for small-scale production, since the matrix remains unharmed and ready for the construction of the next boat.
Having chosen the first method, create, according to the drawings, a set of hulls for the future boat. If this is your first self-build, choose a set of ready-made drawings - this will save you from many problems. It’s worth building a boat according to your own drawings only after gaining some experience.
When building a boat, use only stainless fasteners - brass or bronze screws and nails. The fiberglass fabric used must be annealed blowtorch(but don’t overcook!) until slightly brown. Without such treatment, the fiberglass fabric will be poorly impregnated with the polyester or epoxy resins and the body will turn out to be very fragile.
When choosing a resin, remember that polyester resins are easier to work with than epoxy resins, but the strength of polyester resins is less. To glue the first layers of sheathing you will need glass matting - that is, coarsely woven fiberglass. For the outer layers of the body, use satin-weave fiberglass fabric. At the very top there is fiberglass mesh - a thin, sparsely woven fabric that is well impregnated with resin.
Sand and polish the finished body. This work should begin before the resin has completely hardened. Be sure to work in a respirator, use power tools - it is very difficult to process a large body by hand.
If you choose the second option, first make a matrix. To do this, you will need to create a set that is the reverse of the hull of the future boat. Use polyester resins; the thickness of the matrix walls should not be less than 8 millimeters. The matrix must have stiffening ribs so that it does not “lead”. Remember that the quality of the future boat hull depends on the quality of the matrix surface.
When gluing the body in the matrix, start by applying a separating layer - without it, the body will stick tightly to the matrix. Use floor polish, Vaseline, or wax as a separating layer. After its application, the formation of the boat hull begins. The decorative (painted) layer is applied first; its thickness is 0.4-0.6 mm. Then layers of fiberglass mesh, fiberglass and fiberglass mats are laid in succession. All layers are carefully rolled with a roller to the surface of the matrix.
After forming the body, it is necessary to install (glue in) the internal kit. Do this directly in the matrix, this method will avoid deformations. Make the deck in a separate matrix and connect it to the hull or glue it in place. A body correctly made in the matrix does not require additional finishing or painting.
Surely most fishermen understand why an echo sounder is needed. And the presence of an echo sounder for fishing from a boat is necessary not only to see whether there is fish in a particular place, but also to study the bottom topography and determine the exact depth at the fishing site.
But many novice fishermen make a big mistake by entrusting the echo sounder with only searching for fish. After all, experienced fishermen know that almost all aquatic inhabitants love a sharp change in the bottom topography and almost all the fish are hidden in holes at the bottom, and only by making considerable efforts to study the topography of the reservoir can one accurately say whether the place chosen for fishing is promising.
All the information that you can see on the echo sounder screen is shown in two versions, the first is graphic (lines and diagrams) and digital (numbers in the corner of the screen). It is very important to select echo sounders for fishing from a boat according to the type of craft and method of use. From wrong choice accessory greatly affects the accuracy of the information provided.
If you don't have a better fishing companion than inflatable boat, then you will definitely need an echo sounder, because it will help turn fishing into a real vacation and bring you the desired results.
How are echo sounders useful for PVC boats and what benefits do they bring to fishermen? The main purpose of this accessory is to search for fish in the water column. But that’s not all, it also shows changes in the bottom topography, and experienced fishermen know that fish are grouped precisely at sharp changes in depth and holes. But now, determining the presence of fish in a section of a reservoir fades into the background and the first task of the echo sounder becomes measuring the depth of the reservoir and determining the bottom topography. And if you have a “sophisticated” echo sounder, it will even help determine the water temperature.
And so, if our lines inspired you to buy an echo sounder for fishing from a boat, then you need to know some recommendations and tricks when purchasing. Before you go to the fishing store for the long-awaited accessory, we recommend that you read the article to the end and note for yourself the main qualities that an echo sounder should have.
After researching and determining the features you need in your fish finder, there are some specifications you need to know. And so, a sonar must have: a powerful transmitter, an efficient transducer, a very sensitive receiver and, of course, a screen with high contrast and resolution.
The power (the manufacturer indicates it in Watts) of an echo sounder can be determined by its specification and the power characteristics are as follows:
- RMS (average);
- Peak;
But don’t delude yourself about the very high sensitivity of the receiver, because the more sensitive it is, the more interference you will see on your screen while fishing. It is worth choosing devices with the ability to adjust sensitivity and pay attention to special attention the width of the range of changes, the wider it is, the better.
The echo sounder display is no different from the display of a telephone and other devices with monochrome screens. This is a regular matrix that contains a certain number of pixels. And the more pixels it contains, the better the resulting image will be.
The size of the echo sounder display, as well as its resolution, is a very important indicator. I think it’s logical, the larger the screen you have, the larger the picture, cool, right? If you are buying a black and white fish finder for fishing from a boat, then pay attention to the number of grayscale levels in its screen. The density of a visible object is determined by the level gray on the display. The best and highest quality echo sounders have 16 shades of gray, this maximum quantity shades that the human eye can discern. But with displays that can reflect only a small part of the shades of gray, things are worse; they simply do not see less dense objects at the bottom and are not able to reflect them. The spectrum of shades of gray on black-and-white echo sounder displays varies from 4 to 16.
In any case, using echo sounders for fishing on a PVC boat, be it good or not, you will be ready to actively search for fish and will definitely find it, and this will bring you the desired catch.
Immediately before installing the echo sounder on the boat, carefully determine the mounting location. When choosing a place for mounting, you need to take into account two factors, the first is the shape of the bracket (usually supplied as standard) and the particular shape of your PVC boat. Please note that the accessory sensor must be in a parallel plane with the water surface and be completely immersed in water. It is worth being aware that if you attach the echo sounder sensor at any angle other than 90 degrees, the readings from the device itself may differ from reality.
Also, mounting the echo sounder on PVC boat requires the fisherman to take into account the air that gets under the bottom while moving. Air bubbles that get under the boat while moving can affect the sensor and its readings will not be entirely reliable. Because of this, you need to choose a place to install the sensor so that air exposure to it is as small as possible.
If you have a large inflatable boat, then there should be no problems; the stern would be the ideal place to mount the echo sounder sensor. But here there will be a slightly different problem, the factory brackets are not very strong, and if you hit an obstacle, you can break either the bracket, if you’re lucky, or, if not, the transom. This is at your own peril and risk, but I would immediately replace the bracket with a homemade one, I will have to write an article on how to make it. A mechanism for throwing away the bracket in case of emergency can be a very useful thing; I installed such a thing for myself right away, it helps.
Well, for the truly desperate, you can try gluing the sensor into the hull of the boat itself. ATTENTION, do this only if you are absolutely sure that you will not harm your inflatable boat in any way. This scam can only be pulled off if your boat is made of:
- Rubbers;
- Fiberglass.
To mount the echo sounder inside a PVC boat, you should choose exactly the place on the bottom that will be parallel to the water in any conditions. Well, I won’t describe the installation, I think everyone will have the courage to just cut a hole, put the sensor in there and then seal the boat.
An interesting thing, if you have an inflatable boat, then it supposedly has Velcro, so it’s best to attach the bracket to it. But you need to be very careful so as not to simply lose the sensor; it is best to come up with a more reliable mount. It’s better to attach it to the seat of the boat; a piece of metal-plastic tube can help us with this; we simply bend it and screw it to the seat. We attach our treasured sensor to the other end of the tube.
In short, the whole point of attaching an echo sounder is to attach its sensor. Well, we simply mount the screen in a visible place, depending on your personal preference and desire.
All fishermen know about the existence of echo sounders, even those who cannot afford a boat. Yes, but now there are many echo sounders for studying the bottom and fish without a boat, but they are expensive and not very effective. Well, those who have something to sail on very often wonder about the correct installation of an echo sounder on a boat, and it doesn’t matter whether it is PVC or metal or made of another material, the installation principle is always similar and the main aspects are the same, let’s move closer to them.
In many ways, the quality of the information received depends not only on the coolness of your device, but also on its correct installation and settings. Installing an echo sounder on a boat is quite a complicated thing, and without certain knowledge and skills it is not immediately possible to do it correctly. Very often in the instructions for the device you can find drawings with the approximate or exact location of the sensor, but sometimes only the situation is outlined there for boats with a motor, sometimes only for boats or inflatable watercraft. But what to do if your type of boat is not in the instructions? Just read what I write and make notes for yourself, and if anything is unclear, ask in the comments.
Well, you most likely have already read that the sensor must be parallel to the plane of the water. I wrote half of the article about this. Yes, undoubtedly this is very important, but how to install it, step by step, and write down where you need a screwdriver and where you need a key. Thought you forgot? No, read below.
Below I have attached a video with step-by-step instructions, this is for those who do not particularly know how to read or do not perceive it. My uncle did everything there clearly and will tell you how to do it. Well, for those who perceive printed information, I’ll tell you in more detail, we will need to prepare a Phillips screwdriver and a low-speed drill. There are only two screws, just don’t overdo it with the size, it’s unlikely that anyone will like it if reverse side There will be a self-tapping screw sticking out of the transom. Well, in order not to get your feet wet in the boat, you will need to prepare a moisture-resistant sealant.
If your fish finder is equipped with a sensor that you do not plan to remove after fishing, then it would be better to secure it so as not to tear it off in the future. Yes, if the sensor has a fragile leg, it is better to wrap it with a rag while transporting the boat. Also be very careful about the fragile and thin legs of the echo sounder transducer when pulling the boat to shore. But, if you are as attentive as I am, and still break your leg, there is nothing fatal here. It is very easy to repair this structure, since it is plastic, just heat both parts at the fracture site over a fire or with a lighter and simply fasten them together. The main thing is to stick it directly, the rest is all little things.
The worst idea when installing a fish finder on a boat with a motor is to place the sensor wires near the propeller. It’s better to place the wires completely away from other devices; the echo sounder is very sensitive and interference from neighboring devices can be displayed on the screen.
Many people wonder how to install an echo sounder on a boat with a motor, what obstacles may arise in this case, and much more. And everything is simple, if you see interference on the screen, instead of the image of fish you see some strange arcs, then third-party devices are interfering. If you can only see the top halves of the fish, this may indicate that you need to lower the front of the transducer. Accordingly, if the screen shows the lower halves, then raise it.
Installing the echo sounder on motor boat is not much different from attaching to other types of swimming equipment, except that you need to wash the sensor with soap in order to get rid of a layer of fat (this fat accumulates on the sensor due to gasoline). Dirt and gasoline residues will interfere with the operation of the device and it will not display accurate information.
The coolest and easiest thing is to install an echo sounder on a PVC boat using regular Velcro. Ordinary sewing Velcro is a universal thing; you can remove the echo sounder as needed and quickly install it back. You just need to choose a fairly strong base for the Velcro, such as a seat.
Below is provided step by step instructions on installing an echo sounder on a boat.
- Flattening aluminum tube at one end.
- Then we drill a hole in the flat part for fastening.
- We measure 5 centimeters from the flat edge and bend it at a right angle.
- We bend the tube so that it bends downwards.
- Then we cut the tube at a distance of about ten centimeters from the water, flatten the second end of the tube and attach the sensor to it.
Today, fishermen delight with their creativity and resourcefulness. Installing the echo sounder sensor on aluminum boat here it did not pass without a trace. Fishermen have come up with many designs and almost all of them are successful. The main thing is that the rod is of sufficient length; it should be enough to reach the corner of the transom. It should allow the sensor to be positioned at the level of the bottom of the boat. In the case of a high transom, certain difficulties may arise. But you can permanently install the sensor on the transom.
The second point is the sufficient width of the gripping part of the clamp. It happens that the transom board is so wide that even a completely unscrewed clamp bolt still does not allow it to be placed on the transom.