![]() ![]() As the electrical power industry grew over the past 150 years, the Francis turbine was able to compete with other prime movers in terms of cost, which lead to its widespread use for many applications.ĭue to their versatile design, Francis turbines are suitable for a wide range of pressures and flow rates. James Francis applied mathematical principles when designing the Francis turbine and created a turbine with an efficiency exceeding 90%.Īlthough there are different variations of the Francis turbine now available, the fundamental working principles remain the same as those used over 100 years ago. Waterwheels had been used to complete useful work for over 1,000 years, but they were inefficient. I’ll explore that in a future article.The Francis turbine was invented by James B Francis in the 1850s. Extrusion is the easiest way to turn an outline into a 3D shape, but you can also rotate an outline around one of its edges – great if you need a shape with a circular cross-section. Draw an outline and extrude it to the height you need, then use basic shapes to create any holes or cutouts you need. It takes a little practice to master drawing sketches in FreeCAD, but once you do you can create complex shapes that would be a real struggle to make by adding and cutting the basic ones in the Part workbench. That’s only a small part of what you can do, though – it’s a great way to create parts, too. If you want to print a logo for signs you can either import an image or draw one in the Sketcher workbench. I doubt a lot of other people are looking for silhouettes of battleships, though, so is this method actually any use? I was looking for a silhouette of a battleship, so this worked perfectly. You can go into the Part workbench and add or remove more shapes, chamfer the edges and all the other things you can do in FreeCAD – including, of course, exporting it as an STL file and loading it into Cura, all ready to print. Once your sketch is extruded, it’s just another 3D shape. Then it will create a shape inside the outline of the sketch, and extrude it. Your computer will whirr busily for a few seconds, then come up with a menu asking what height of pad you want to create – in other words, how much you want to extrude the shape by. You’ll get asked how to handle the selections go with “Make independent copy”. Then select the sketch, go to the Tasks window and click on the Pad tool. Now go to the Part Design workbench, create a new body and double-click it to make it active. You can hide or delete all the paths and original sketches now, leaving your final one. This will create a new sketch out of all the original ones. Now go to the Sketcher workbench, select all the sketches, open the Sketch menu and click Merge Sketches. This will create a sketch for each of the paths imported in the SVG file. Next, select all the remaining paths, open the Draft menu and click Draft to Sketch. ![]() ![]() I deleted a few small elements – like the propellors – that I didn’t want in the final model. The SVG will open as a collection of separate “paths” that make up a simplified outline of the drawing.Īt this stage you can make some tweaks. You’ll get a choice of opening it as a drawing or geometry pick geometry. Next, open FreeCAD and go to the Drafts workbench choose Import from the File menu, then find the SVG file and open it. I did this with an online converter that simply converts the file and downloads it to your PC. The first step is to turn the drawing into a format FreeCAD can read, which means an SVG file. ![]()
0 Comments
Leave a Reply. |