WITH NEEDLE AND RESIN

“Sunwski” — small boats that make the guys on “Pioneers yard” of the city of Astrakhan on well-proven technology. The main principle consists in wrapping the frame with fiberglass impregnating epoxy resin, which, solidification, forms a strong shell. By itself, it is of course, Nenov. However, it has features, which allows to significantly simplify the construction.

 

Fully preparing a first frame of the boat, the longitudinal edges of the wooden slats of the calculated thickness. The distance between adjacent stringers on highly curved surfaces must not exceed 100 mm. So, for large cambers, for example, in two directions it is recommended to put additional edges — thin strips: they will reduce the sagging tissues. You can also cover tight to the frame with nylon thread (crosswise) with an interval of not more than 50 mm. All the parts of the boat, which in the process will be in contact with glass should be well cleaned coarse sandpaper.

 

Technical manuals require before pasting the fabric to anneal at 200-250° (this is usually done with a blowtorch), or to clean out the sizing substances in acetone. However, for our work, as experience shows, is quite good enough to warm it in the oven of a gas stove to evaporate moisture and to “visarite” oil.

 

Cut out the fiberglass “sunwski” it is necessary so that the edges remained about 100 mm allowance. If fabric width is insufficient, it sew the overlap, with an overlap of 20-30 mm. Superimposed on the frame the fabric is stretched from the keel to the sides, and then along the body and secured with thin nails, but so as not to modify the natural tension of the fabric. “Raids” can be cut as well, laying the edges overlap and stitching them. They will be formed mainly in the bow — lines: our boats are designed so that they have straightened the hull and flat transoms. Remaining on the sides of the allowances are wrapped vnatyag for RUB rails and transom frame and sewn with nylon thread. After this impregnation of the casing is placed on the keel and again checks the quality of the stitched: folds and wrinkles should not be.

It should be noted that the hull of our boat has an extremely simple structure. Set bottoms, for example, consists only of fin and a pair of longitudinal ribs, passing into the bilge stringers. Cross set of two braced frames in the front part and the transom, which is simultaneously the binding of the transom Board, is made of plywood. The keel splits into a stem associated Carling with the first frame. Going over the RUB rails. All fused between the same epoxy.

 

 

Fig. 1. The frame of the boat.

 

 

Fig. 2. Pinning the fabric on the frame.

 

Impregnation of fibreglass with resin is provided in the usual way. However, it is possible to recommend to add a minimum number of curing components to more benign was curing, and to increase the dose of plasticizer to decrease the fluidity of the binder, especially on the sides. It is necessary to conduct drying at a temperature of 25-30°, and the boat should stand on “even keel”.

It is desirable to applied to the wall all the layers to obtain a predetermined thickness without long breaks. Otherwise you’ll have to strip the previous layer. If you have experience in the use of resins, it is possible to fit the body at the same time two or three coats, but you have to be very careful at work, especially for fear of bubbles.

 

In the manufacture by this method, a small boat usually imposed a maximum of two layers of fiberglass. “Sunwski” we wrap four layers of thickness 0.3—0.4 mm. That is enough to get a solid elastic shell.

 

 

Fig. 3. “Crosslinking” of nylon thread.

 

 

Fig. 4. Boat after wrapping is ready for impregnation.

 

Operation of boats in the past few years has shown that they have little worn, the possibilities of punctures are extremely limited, and if this happens, the repair is very simple. Just want to once again warn about the need to observe all safety rules when working with epoxy.