Idiot's Guides: 3D Printing (2015)
Project Time: 20 minutes
For your first 3D CAD modeling project, you’re going to start with something simple that you can proudly display on your coffee table (until your spouse makes you move it). You’re going to be modeling a custom-monogrammed coaster!
This should be an easy first project. You’ll just be modeling a basic circular plate and cutting a letter into it. This will also be easy to print after you’ve modeled it.
Open Your CAD Program and Create a New Part
Obviously, the first thing you’ll need to do is open up your CAD program. (In this example, like all of the others, I’ll be using Solidworks.) When the program is open, you can create a new part. For this example, I’ll be using millimeters. If you’d prefer to use inches, just divide those dimensions by 25.4.
Extrude a Circle
To create the main body of the coaster, you should start by extruding a simple circle. You need to select a plane to sketch on for the extrude command. Choose whichever plane makes the most sense to you for that specific part, but keep in mind that you might need to rotate the part when you slice it in order to orient it properly. So under the Features tab, find the extrude command in your software and select Front Plane.
Extrude from the front plane.
The CAD software should then switch you to the sketching toolbar (or it may already be open); in this software, you click the Sketch tab. Select the circle icon (defined by the center point) and click on the origin point to place the center of the circle there. You can then just drag the circle out a little bit.
Choose the dimension command in your software (you may need to choose the diameter type specifically) and select the circle. This will place a dimension that defines the diameter of the circle. You can then modify the dimension to fit your needs; in this case, you want it to be 100mm.
Give the circle a diameter dimension of 100mm.
With the diameter of the circle defined, you can go ahead and extrude it. There should be a button for completing the sketch (in Solidworks, it’s a green check mark, as you can see in the following image), which will take you to the feature’s options. In those options, give it an extrude distance of 10mm.
Extrude the circle 10mm out.
Fillet the Top Edge
Next, you want to fillet the top edge of the coaster. This will give it a nice, rounded top. Rounding the top will make it more aesthetically pleasing and will also keep it from having a sharp uncomfortable edge.
Click on the Features tab and select Fillet. Using the Fillet tool, select the top edge of the coaster. Under Fillet Parameters on the left, specify a radius of 5mm. Because the top and side meet at a 90° angle, the edge will be rounded down 5mm on the side and in 5mm on the top. (Remember, fillets are defined by the radius of a circle that is tangent to both surfaces.)
Fillet the top edge of the coaster with a 5mm radius.
Cut the Letter
The final feature to add to the coaster is your initial (or initials) cut out. This will be added with the extruded cut command in your software. After choosing the command in the Features tab, select the top surface of the coaster to sketch on.
Before you add the letter, you first need to add a guide to position the text. You could just eyeball it and place it where it looks good, but as I’ve taught you, it’s better to fully define everything. The text (for a single letter) will be 60mm high, so in order to center the letter on the coaster, you need to put a construction line 30mm below the origin.
Start by clicking the line icon to draw a horizontal line below the origin point. You then change that line to a construction line so it’s not used for the feature by right-clicking on the line the checking the “for construction” option in your software. Add a dimension to put the line 30mm below the origin point.
Add a construction line to use as a guide for the text.
You can now go ahead and add the text. In the text command of your software, select your construction line as the guide. Next, change the font options so the text is centered and is 60mm tall. Choose a font style that suits your tastes, and then type in whatever letter you’d like to use.
Cut the letter all the way through the coaster.
Finish the sketch to move back to the extruded cut options in the Features tab. You can either specify a cut distance of 10mm or simply choose Through All (or however it’s specified in your software), which will cut through all of the material in that direction. Or you can just cut in a couple of millimeters if you don’t want it to go all the way through. Complete the feature, and your coaster will be finished!
Once the cut has been done, the coaster is finished!
Export the .STL File and Print
If you’re satisfied with how the model turned out, you can export it as an .STL for printing. The steps to export the file will depend on your specific CAD software, but generally you’ll either “save as” or export as an .STL. When you export it, be sure to choose millimeters, because that’s probably what your slicing software will be set to as the default. You also want to save it at the highest-quality settings, because this model has lots of curves in it.
With the .STL file in hand, you can go ahead and print it. This model won’t require any special settings to print, so just use basic settings. You can then simply start your print and let it cool afterward, and soon enough, you’ll have your very own monogrammed coaster!
Your printed coaster (if your initial happens to be “C” ).