DE2425208A1 - DISPOSABLE INNER SHAPE FOR THE CONSTRUCTION OF BOATS MADE OF FIBERGLASS REINFORCED RESIN AND PROCESS FOR BUILDING A BOAT WITH THIS SHAPE - Google Patents

Description

DR. ING. E. HOFFMANN · DIPL. ING. W. EITLE · I) K. RBR. NAT. K. HOFFMANN O-8000 MÖNCHEN 81 ARABELLASTRASSE 4 TELEPHONE (0811) 911087

25 468

Jan William Dorfman, Toronto, Ontario / Canada

Disposable inner mold for the construction of boats made of glass fiber reinforced Resin and method of building a boat using

this form

The invention relates to a balloon-like boat shape for use in the construction of boat hulls with a bow and a stern, at least the bow tapering to a point, and with. Sides and a bottom, with the trunk resting on the balloon shape when inflated.

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Building fiberglass boats usually involves manufacturing an inner or male mold. The surface of this inner mold is then polished to a mirror finish, and a female mold, i.e., an outer shape, is then built on top of the inner shape. This outer shape is usually built up in two longitudinal halves, and once assembled, the boat is then built by laying successive layers of fiberglass, the outermost layer of the article being in contact with the inner surface of the mold. This way it becomes a boat built with a perfect, smooth outer surface and with a Inner surface that is a bit rough and raw. However, this internal roughness usually does not matter because it disguises will.

The construction of an inner mold with the subsequent construction of an outer mold is an extremely expensive and time-consuming process and significantly increases the cost of building such items.

New construction techniques with glass fiber reinforced plastic have been developed, according to which the boat is built from the inside out. With this type of construction, all that is required is the construction of the inner mold and then the laying of the fiberglass material begins from the inside of the boat hull. In this way it is unnecessary to provide a very high degree of good appearance on the surface of the inner mold, since the inner surface of the fuselage is in any case disguised. The application of this technique led to the development of new building materials and techniques including the so-called "sandwich ¹ · materials, e.g. plastic foam panels and balsa wood, and the development of a suitable form of material or filler or spatula for producing a smooth outer surface, e.g. talc or a special one developed filling material known as “micro-balloons.” Using these techniques, it is possible to build a boat with a glass fiber reinforced inner shell, an intermediate layer of sandwich material, e.g. plastic foam or balsa wood, and an outer glass fiber plastic layer, with the outer glass -

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fiber plastic layer with a layer of synthetic resin and Filler material, ζ.B. Talk or miero-balloons, is finished, which can then be very easily sanded down to a satisfactory appearance.

However, while it is a significant improvement over the old way of building, this style of construction is also required nor the manufacture of a precise internal shape, which is usually constructed from wood.

The consequence of the requirement for the construction of the inner form is usually, that these improved techniques are inaccessible to the average do-it-yourself builder. In most cases it can he does not build the inner mold himself, and it is uneconomical for the manufacturer to build the inner core and it To be sent to self-builder. The consequence of this is that the common practice in the trade is to remove the boat hulls in a factory and either finish the hull in the factory or send it to the new owner's home, where he can buy it can finish it yourself. In either case, the cost of completion or shipping is substantial and incremental the basic cost of the fuselage considerably, as well as the labor share of the costs in the factory of the fuselage itself and also bear significantly contributes to the final price.

The invention is therefore based on the object of an inner shape for a boat that a self-builder can make himself and on which he then build the hull of the boat himself can.

According to the invention, this object is achieved in that fields flexible, non-stretchable plastic material cut to size and attached to each other in a predetermined, cut-to-size hull shape are attached and at least one pointed end portion, corresponding to the shape of the pointed bow of the fuselage, on one End of the hull shape have that the fields with a collar

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are provided along one side of the hull form for fixing the form in place on a base plate, and that the plastic material after the aforesaid fastening can be inflated to its predetermined, tailored size To assume the shape of the hull.

In this way the best economy is achieved, which leads to increased consumption of glass fibers and synthetic resin and Sandwich core material leads and a greater interest in boating and self-building boats, as well as a more profitable use of the self-builder's leisure time.

There are already portable molds or molds for hollow ones Objects or structures have been proposed in the past, which are usually based on the principle of an inflatable Body were based. Such inflatable shapes, however, were relatively raw and clumsy and only suitable for building structures, which had simple, regular, geometric contours. These known facilities were unsuitable for the construction of boats, because boat hulls have complex, convex and concave composite curvatures that are built to tight tolerances must to comply with the requirements of the draft.

Thus, the invention provides a disposable inner mold or mold for building a boat hull which consists of a hollow hull-shaped shape made of flexible, non-stretchable plastic sheet material, which in the form of the inner Surface of the boat hull is cut. Devices for fastening this shape are in the opposite position provided on a base plate and means for inflating the mold to make it its predetermined, unstretched, tailored Takes on the shape of the hull. In addition, control devices for the contour are provided, which support parts of the form, to keep them in their tailored hull shape.

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The control devices for the contour course are advantageous provided in the form of internal supports which are attached within the inflated form and the same from the inside support here.

The control devices are also advantageous in the form of a Base plate is formed to which the mold is attached, wherein the base plate is deformed to a predetermined course, to control the contours of the shape.

It is also advantageous to provide a balloon-like shape for manufacturing a boat with a transom stern, the shape has an open end that corresponds to the mirror for receiving a rigid plate.

Inner supports for the tips are also useful Ends of the mold provided;

The invention also provides a method of making boat hulls using disposable inflatable molds created.

The foregoing and other aims are derived from the following Description of a preferred embodiment of the invention explained in more detail with reference to the drawing. It shows:

Fig. 1 is a perspective view of a mold according to the invention for a boat hull, which is on a base plate constructed and inflated with part of the mold cut away to show the inside.,

FIG. 2 shows a section along the line II-II of FIG. 1, 3 shows a section along the line III-III in FIG. 1,

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Fig. 4 is a perspective view of a boat hull with a deck mold for producing a part of the deck, which is shown attached here,

Fig. 5 is a perspective view of a boat hull in which a further mold is attached to a to make another part of the deck,

6 shows a perspective illustration of a boat hull, in which a further mold for the production of the car roof is installed, and

7 shows a section of another embodiment.

In the drawing it can be seen that the invention consists of a flexible, boat-shaped form 10 made of non-stretchable Plastic is made.

The form 10 preferably consists of a plurality of fields 12. The fields 12 are cut to size and welded together, preferably by heat sealing or ultrasonic welding techniques, but they can also be stapled or adhesive instead Gluing be glued. The cutting and fastening of the panels 12 are carried out according to a predetermined pattern, the shape of the mold 10 being cut to match the hull shape as shown in FIG matches the internal dimensions and contours of the hull of the boat to be built. The plastic material consists of non-stretchable plastic sheets, such as those used for other shapes inflatable roofs are used as they are for temporary buildings. Construction sites and the like can be used. This Material is, depending on the size of the structure to be built, available in a wide variety of thicknesses.

The mold 10 is provided with a circumferential lip or a collar, and the collar itself is on a mounting plate or

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Base plate 16 attached. Preferably the do-it-yourself A paper template is given which shows the outline of the deck plan of the boat, and the builder then marks the Base plate with this outline to ensure that the collar 14 of the mold 10 is secured in exactly the correct position.

Preferably, the base plate 16 is made of pliable plywood or can also be made of other bendable sheet material, e.g. a plastic or hardboard.

The base plate 16 is on a row at a distance from one another arranged cross member 18 attached. The cross members 18 themselves are mounted on longitudinal beams 20. The cross members have different ones Heights; they decrease in height from the stern of the boat to the bow attached, and at the bow of the boat the base plate 16 is directly attached to the side rails 20 or any other not shown cross member. This way the base plate becomes 16 deformed into a continuous curve which forms the shear line of the shear deck of the boat. Form is cut to match the curvature of the base plate 16 adapt so that the mold 10 by the storage of the base plate 16 in this predetermined, continuous curve by the base plate 16 in its predetermined, cut, hull-like shape is held.

The self-builder is preferably given a set of templates showing the exact height of each of the cross members 18, and another set of templates or guides or patterns which show exactly how far they are spaced from one another the length of the side members 20 must be arranged.

The structure of the mold 10 is such that the aft end of the mold 10 is open, i.e. that there is no plastic plate, so to speak is present, which forms part of the mold 10, the

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Would match the stern or transom of the boat.

This part of the mold 10 is formed by a rear plate 22 made of wood or similar material, which corresponds to a profile the profile of a sample or a template sent to the self-builder, which corresponds exactly to the profile of the stern corresponds to shape 10.

The rear panel 22 is attached to a predetermined location on the base 16, and the mold 10 is wrapped around the rear panel 22 in any suitable manner not shown, such as by nails, staples, mastic or the like.

The collar 14 of the mold 10 is preferably secured, as shown in Figure 2, for example by fastening screws 24 to the base plate attached, which go through the wooden retaining strip 26, creating a good airtight seal between the Bund 14 and the base plate 16 is brought about.

Any suitable means of inflating the mold 10 may be used e.g., a fan 28, which is attached to the opening 30 in the rear panel 22. The fan 28 should preferably be provided with a motor which is sufficiently powerful that it may run continuously for a few days can, and the fan 28 must be of sufficient size to maintain the mold 10 in a stable, relatively rigid condition, while the first glass mat is placed.

In order to control the course of the mold 10 further, there are internal supports provided in the form of inner support bars 32 which are attached to support frames 34, which in turn in pairs are attached to transverse spacers 36. Each spacer 36 and its pair of support ribs 34 are on with Spaces arranged at a distance from one another over the length of the base plate 16, in accordance with a predetermined pattern,

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which was given to the self-builder.

To support the bow section of the mold 10 and to keep it in its predetermined, tailor-made course, is a further support part 38 is provided which has a predetermined course that corresponds to the inner course of the bow section of shape 10 matches. The support part 38 is also held by means of the support strip 40, which is shown in the manner shown is attached to one of the spacers 36.

In practice it has been found that with this extent Internal support many boats of various sizes can be built without difficulty. In some cases, however, e.g. depending on the particular course of the hull shape of the boat or in the case of larger boats, it may be desirable to have an additional one Provide a support bar, e.g. an additional optional Support spar, as shown in broken lines in FIG. 2 as support spar 42. The support spar 42 runs along the central longitudinal line of the form 10 from the bow to the stern and is also shown at intervals with dashed lines Support strips 44 stored.

It is understood, however, that the additional support spar 42 and the support strips 44 are optionally used and, strictly speaking, are not necessary in the majority of cases.

For assembly, the do-it-yourself builder receives the inflatable form 10, a fan 28 and a number of support ribs 34 and can also received a rear plate 22. He will also provide a full set of the patterns or templates for marking out the locations the fastenings of the various other parts preserved.

He will then have a supply of wood or other suitable material and using the stencils or patterns he draws the exact location of the attachment of the various Parts on the base plate 16 and provides the corresponding

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Cross member 18 with the appropriate size and marked their exact location on the longitudinal members 20. Then he attached the various parts together and fastened the support bars 32 in place on the support frames 34. He then fastened the Mold 10 in position over support bars 32 and secures collar 14 of mold 10 along predetermined markings, which he has already drawn on the base plate 16.

Then he installs the blower 28, attaches the mold 10 to the curved part of the rear panel 22 and turns on the blower, to inflate the mold 10.

The mold 10 is immediately inflated and takes its predetermined, tailored hull shape and remains in this shape as long as the fan 28 is running. Obviously a certain one becomes Leak out proportion of air; however, as long as the fan 28 is running, this does not lead to any difficulties, and so does the mold 10 remains at least essentially rigid for boat building or at least sufficiently rigid to place the first glass mat to be able to. Of course, once this first inner layer has set it will have sufficient inherent rigidity so that the mold 10 is no longer necessary and the fan 28 can be turned off. For security reasons however, it is usually preferable to keep the fan 28 running while the sandwich layer of plastic foam is being laid or other material. This is the reason why plastic foam is used as a sandwich material preferable to other materials for this type of construction. Other sandwich materials such as balsa wood and the like can be suitable if they are flexible enough. Some materials are too stiff and must be held in place with special fasteners, and this naturally leads to difficulties with the mold 10, which consists of a hollow, inflatable structure. If on the other hand the special one Plastic foam is used as a sandwich material, this material can be kept flexible enough so that

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AA

it simply in place over the inner fiberglass layer attached and with the inner fiberglass layer can be glued by additional resin. The outer fiberglass layer is then placed on the sandwich material, and when it has set, the structure can be completed with a Layer of resin and putty to be completed.

After completion, the hull can then easily be removed from the mold 10 can be lifted off, and the mold 10 can then simply be thrown away when it is no longer needed, or in some cases, if it was not damaged when the hull was removed, it can be reused.

The completion of the hull of course, includes the insertion of a suitably shaped plate in the stern of the hull and other finishing works _f which are normally required in boat building.

It is seen that in the practice of the invention an economical, simple form of an inner boat shape is created, e.g. through the post office or district sales outlets can be shipped and sold, or in any other place, even by a relatively inexperienced person Self builders with a minimum of difficulty can be used to make a boat hull to a high standard of accuracy and appearance with a minimum of specialized tools or knowledge.

At the same time, great flexibility in the design is achieved, because the shape of the mold 10 is entirely due to the blank of the fields 12, the design and bending of the base plate 16, the clamping and production of the courses of the shape and also is controlled by the inner support bars 32. So it is possible to use a wide range of different designs experiment with a minimum of mold costs.

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According to further exemplary embodiments of the invention, it is possible build the deck and the canopy of a boat in different stages. These stages are one after the other in the Figs. 4, 5 and 6 are shown.

A boat hull 50 is shown in FIG. 4, and the forward deck section can be constructed by means of the inflatable form 52 around the front and middle part of the fuselage 50 with the mounting flange 54 and suitable fasteners., e.g. nails, staples or the like.

To complete the inner part of the hull 50 is a wooden one Frame 56 is fitted into the hull 50 and the rear part of the mold 52 and attached thereto by means of the mounting flange 57 attached. An opening, not shown, is cut into the bulkhead 56, and the fan 28 is connected to it attached to blow air into the closed front portion of the fuselage 50. In this way, the shape 52 becomes the desired one The shape is inflated and, as before, glass fiber reinforced plastic can be applied together with the sandwich material will. Because it will be desirable to form the forward deck portion of the hull 50 with a cabin end the form 52 is provided with a suitable marking 58, and the deck of the hull is only up to the limits of the marking 58 laminated. Upon completion, the laminated foredeck section 60 is lifted off the mold 52, and the mold 52 can then simply be stripped off and taken away. The foredeck section 60 is then re-contacted in place brought with the fuselage 50, and with suitable connecting means, e.g. glass fiber reinforced plastic, the foredeck section and hull are attached to each other.

To complete the aft section of the deck or a Suitable covering around the cockpit of the boat, the bulkhead 56 remains in place and the fan 28 simply comes in from the rear of the bulkhead 56 removed and attached to the front.

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away

Another mold 62 is then attached in place by means of the mounting flange 64 and the same process is still carried out performed once. Because it is not desirable to fill the entire area of the cockpit, it is again a suitable one Marking 66 is provided on the form 62 to indicate the limits to which lamination is to be carried out. When this is finished, the deck section designated by 68 in FIG. 6 is removed, the mold 62 is stripped off and put away, and the deck section 68 is then put back in place and secured in the manner previously described.

To complete the car roof, the fan 28 is removed again from the front of the bulkhead 56 and from its rear attached. An additional bulkhead 70 is then attached to the top of bulkhead 56. The frame part 70 is shaped so that it forms the profile of the canopy. Another inflatable form 72 is then attached to the edge of the foredeck section 60 and attached to the additional frame part 70. The fan is then switched on again and the car roof can laminated over the mold 72. The fan 28 is then removed and a suitable door opening or opening can then be made Cabin companionway cut into frame 56 and the additional frame part 70 and part of the cabin roof (not shown) will. It is then possible to regain access to the interior of the fuselage and the mold 72 can then be placed underneath the Canopy can simply be stripped off.

So it can be seen that in the practice of the invention it is possible to have both a boat hull and a Build deck and a canopy in successive stages, using inflatable shapes, using different shapes Sections of the fuselage and inflatable forms are connected together in different stages of construction.

It will be understood that when building larger boats, for example, a greater number of steps may be introduced in order to

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to create a greater variety of deck and cockpit designs and e.g. a center cockpit with a fore and aft cabin or any other modifications in construction that are desired.

While in connection with the embodiment of Fig. 1, 2 and 3, the inflatable form 10 is attached to a rectangular base plate 16 in accordance with a marking line made thereon, it can of course be seen that this is System can be modified a little for some designs. This design tends to create a flange or rib, which extends around the outside of the boat hull, around the Schergang or Schandeckel. With some boat or boat hull shapes this can be undesirable. To avoid this, the base plate itself can be in the form of the flat outline of the fuselage, and the mold 10 can easily be attached to the edge of such a base plate 16, which is then bent over the cross member 18 in the manner shown and described. This way the top edge becomes of the boat is not limited by an outwardly directed flange, and this can be advantageous with certain hull shapes be.

It is believed that 'such a modification is evident from the figures the drawing and the description is recognizable, and that no further representations are necessary.

The invention can also be used to build a canoe or a boat hull which tapers to a point at the bow and stern. As As shown in Fig. 7, this embodiment includes a mold 80 made from multiple panels which are cut and welded together to form the hull shape of a canoe. The different fields of the form 80 are in this illustration is not shown for the sake of simplicity.

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The mold 80 is attached to a base plate 82 in the manner described. To create a shear line for both the bow and Also to form the stern of the canoe, the base plate 82 is mounted in a continuous curve on the cross members 84, which in turn are mounted on longitudinal beams 86. The cross members 84 are highest in the middle and toward the Ends of the side members slightly shorter, and the base plate 82 is attached to the cross members 84 in the manner shown to form a smooth, regular curve from bow to stern.

The bow end of the mold 80 is supported by the bow support 88 and the support bar 90. The bow support 88 is preferably one suitable plank cut according to the profile to form the profile of the bow inside that to be built on the form 80 Form canoes.

The rear end of the mold 80 is supported by a similar rear support and support ledge 94. The through the rear support 92 formed shape may be the same or slightly different from the course of the bow support 88, but works essentially in the same way, i.e., forms the profile about which the rear end of the mold 80 is stretched when the mold 80 is inflated.

The interior of the mold 80 is supported in a manner similar to before from the bow to the stern by means of internal support spars 96 which on Support ribs 98 are attached, which in turn are attached to the base plate 82. The support ribs 98 are spaced or at so-called stations along the length of the interior of the mold 80, as described above.

To inflate the mold 80, a suitable opening 100 is in the base plate is provided, and the fan 102 is at the opening attached to bring air into the interior of the mold 80.

It goes without saying that the blower is supplied as part of the kit or can be obtained separately from the purchaser

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can. The term "means for inflating" as used in the claims is therefore intended to mean any opening or opening Enclose conduit through which air can be brought into the mold and is not limited to a blower alone. For example, a house vacuum cleaner used with a suitable governor or speed controller could possibly be used will.

While the mold 10 is shown with an open end into which a rear panel 22 is inserted, it could be with a rigid plate of any suitable material, e.g. wood, rigid plastic or the like, which is permanently attached to it to be instantly attached to the base plate.

The use of the embodiment of FIG. 7 takes place essentially in the same way as was described above,

Briefly summarized, the invention creates a removable inner mold or form for building a boat hull, which consists of a hollow, trunk-shaped form made of flexible, non-stretchable plastic material, which is in the form of the Inner surface of the boat hull is cut. There can also be means for fixing the mold in the inverted position on a baseplate, means for inflating the mold so that it is its predetermined, non-stretched, tailored Hull shape assumes, and contour control means for supporting parts of the shape are provided around them keep in their tailored hull shape. Furthermore, the invention also provides a method for producing covered or partially covered boat hulls specified using flexible shapes.

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Claims (16)

Claims 1. J balloon-like boat shape for use in the construction of boat hulls with a bow and a stern, at least the bow tapering to a point, and with sides and a bottom, the hull being made on the balloon shape when it is inflated, characterized in that Fields (12) of flexible, non-stretchable plastic material are cut to size and attached to one another in a predetermined, cut-to-size hull shape and have at least one pointed end section, corresponding to the shape of the pointed bow of the hull, at one end of the hull shape, that the fields (12) with a Collar (14) are provided along one side of the hull form for securing the form in place on a base plate (16) and that the plastics material, after the aforesaid securing, can be inflated to assume its predetermined, tailored hull shape. 2. Form according to claim 1, characterized in that g e * k e η η that four fields of the material extending in the longitudinal direction of the hull shape are provided. 3. Form according to claim 1, characterized in that the collar (14) has a line of curvature corresponding the line of curvature of the hull of the boat hull. 4. Form according to claim 1, characterized in that the rear of the fuselage is flat and one Forms connection line with the sides and the bottom, and that the mold (10) at the end remote from the pointed end is open and forms a shape corresponding to the connecting line on the flat mirror and is suitable for receiving a rigid rear panel (22). - 18 - 409850/0358 5. Form according to claim 1, characterized in that a control device for the contour course for supporting parts of the mold (10) to hold them in their predetermined, tailored, unexpanded body shape. 6. Form according to claim 5, characterized in that the control device for the contour course of at least two inner support bars that can be attached within the mold at a distance at a predetermined height (32), which touch the inside of the mold to support it and thereby control its course. 7. Form according to claims 5 and 6, characterized in that a base plate (16) is provided is what the facilities for controlling the contour course forms that the base plate is curved in a predetermined shape, whereby its contour is controlled, and that it is mounted according to the predetermined shape of the trunk. 8. Form according to claim 7, characterized in that the base plate (16) carrying cross members (18) are arranged at intervals over the length of the mold (10), and that the cross member (18) variable dimensions have, whereby the base plate (16) in the curved position is held. 9. Form according to claim 5, characterized in that the control device for the contour course a rigid rear panel (22) disposed at the aft end of the mold (10) so that the rear panel is shaped is that it coincides with the transverse profile of the fuselage at the stern, and that the shape (10) is fixed around the contour of the stern plate (22), whereby it is in its predetermined, tailored hull shape is kept. - 19 - 409850/0358 10. Form according to claim 9, characterized in that an opening in the rear plate (22) (30) is provided, and that a fan (28) is connected to the opening (30) for inflating the mold (10). 11. Form according to claim 5, characterized in that the control device for the contour course a plate-like support member (38) having an edge which corresponds to the internal profile of the pointed end of the mold (10) matches, as well as a support bar (40), which is used to support of the support part (38) is attached to the base plate (16). 12. Mold according to one of claims 7 to 11, characterized in that an opening is made in the base plate (16) , and that a fan (28) is connected to the opening for inflating the mold (10). 13. Mold according to claim 1, characterized in that both ends of the mold (80) are pointed, and that a base plate (82) is provided which is curved in a predetermined shape, that the mold (80) on the base plate (82 ) is attached and is substantially pneumatically sealed against the same that bow and stern supports (88; 92) are attached to the base plate (82) and have a profile shape that corresponds to the interior of the bow and stern ends of the mold (80) that inner support bars (96) mounted on the base plate (82) are provided within the mold (80) and extend from one end to the other and are arranged to contact the interior of the mold (80) when the same is inflated, whereby sections of the mold are arranged and held in their predetermined, tailored hull shape when they are inflated, that an opening (100) is provided in the base plate (82), and that a fan (102) with the opening (100 ) to inflate sen of the form (80) is connected. - 20 - 4098t,: / C j 5 8 14. Method of making a boat shape using at least part of a deck in successive stages, characterized in that a hull is made with an uncovered top, that a bulkhead is attached amidships in the hull, that a flexible, non-stretchable shape from one end of the boat hull to the bulkhead and is attached to the free edge of the bulkhead and the same pneumatically seals substantially that the interior of the is inflated by the bulkhead and the flexible form enclosed boat hull, whereby the form is inflated and causing an upper portion of the boat to assume a predetermined, unstretched shape over at least a part of the flexible mold is made and then the flexible mold is removed. 15. The method according to claim 14, characterized in that a further flexible shape between the stern of the fuselage and the bulkhead is attached, the same inflated and at least part of the upper part of the Boot over the mold and the same is removed. 16. The method according to claim 14, characterized in that a further frame part is attached to the frame is, another flexible form is attached to the other frame part and the newly manufactured part of the fuselage that the mold is inflated so that a further roof section of the boat is made on the further mold and the further mold Will get removed. 409850/0358