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.25").Do this in the Front viewport.This will form the straketrimming curves for the tops of each strake.Change these curves to layercStrakeTrimmingEdges.Offset the inboard edges of the horizontal strake surfaces outboard by this distanceas well.This will create the trimming curves for the inboard edges of the runningstrakes.Rebuild the resulting curves, and use the SetPt command to move their forwardpoints to coincide the forward ends of the strakes, so that all curves and surfacescome to a point at the rabbet.174Rhino Marine: Offshore Racing Power BoatExtend the trimming edges beyond the edges of the surfaces fore and aft to ensuresuccess in the trimming operation.Extend the offset strake trimming edges.Strake trimming edges constructed.Step-by-Step: Create the trimming curves for the strakesCreate the strake trimming curves1 Start the Offset command.2 Set the distance to 0.25".3 In the Front viewport, select the upper edge of the vertical surface of theoutboard strake.4 At the Side to offset & prompt, in the Front viewport, pick a point below theoutboard running strake, so the curve is offset "down."5 Repeat these steps for the inboard running strake.6 Repeat the Offset command.7 In the Top viewport, select the inboard edge of the bottom surface of theoutboard running strake.8 At the Side to offset & prompt, in the Top viewport, pick a point outboard ofthe outboard running strake.9 Repeat these steps for the inboard running strake.Rebuild the strake trimming curves1 Select all four strake trimming curves you just created.2 Start the Rebuild command.3 Complete the Rebuild dialog box specifying 10 points and degree 3.175Rhino Marine: Offshore Racing Power BoatModify endpoints at the forward end1 Select all four strake trimming curves.2 Use the PtOn command to turn on the curves control points.3 Select the points at the ends of the trimming curves for the outboard strake.4 Start the SetPt command.5 In the Set Points dialog box, check Set X, Set Y, and Set Z, click Align toWorld, and click OK.6 At the Location for points & prompt, use the End object snap to select theendpoint of the outboard strake edges.7 Select the points at the ends of the trimming curves for the inboard strake.8 Start the SetPt command.9 In the Set Points dialog box, check Set X, Set Y, and Set Z, click Align toWorld, and click OK.10 At the Location for points & prompt, use the End object snap to select theendpoint of the inboard strake edges.Use the SetPt command to move then end control points together.11 Press Esc to turn off the Control Points.Extend the outboard strake trimming curve1 Start the Extend command.2 At the Select boundary objects & prompt, press Enter to start Dynamicextend.3 At the Select object to extend & prompt in the Right viewport, select theforward end of the outboard strake s outboard trimming curve.Extend the offset trimming curves fore.4 At the End of extension prompt, pick a point forward of the endpoint of thestrake.176Rhino Marine: Offshore Racing Power Boat5 Repeat these steps for each end of each strake trimming curve fore and aft,making the ends extend beyond the ends of the strake surfaces.Strake trimming edges constructed.Create a blend surface between the strakes and hullNow that you have constructed the strake trimming edges, trim the strakes to theseand the strake surfaces will be ready for blending to the hull.One way to fillet two surfaces with a variable radius is to make the surfaces withedges touching, trim the edges back an amount equal to the radius, and create ablend surface between them.The actual shape of any station on the surface, whileapproximating a radius, is not an actual radius.Allowing Rhino the freedom to use theappropriate shape at any station means the fillet will go much more smoothly,especially in cases where the fillet requires variable radius.The surface created withthe Blend command will be guaranteed to be curvature continuous (G2).To finish the strakes, use the BlendSrf command and select two adjacent edges.Make certain the Continuity option is set to Curvature.Rhino will construct a surfacebetween the bottom surface and strake surface that is curvature continuous (G2) fromstem to stern and comes to a point at the bow.Step-by-Step: Create a blend surface between the strakes and hullTrim the strakes to the strake trimming edges1 Select all four strake-trimming curves.2 Start the Trim command.3 At the Select object to trim & prompts, in the Front viewport, trim the edgesof the vertical strake surfaces above of the trimming curves.4 At the Select object to trim & prompts, in the Top viewport, trim the edges ofthe horizontal strake surfaces inboard of the trimming curves.Blend the strakes to the hull1 Start the BlendSrf command.2 At the Select first set of edges & prompt, select outboard edge of the theinboard bottom surface [ Pobierz całość w formacie PDF ]