For this step we are creating a plate.
With DupBorder command we need to extract border curves and use the inner surface to do that.
We’ll use the inner circle and using PlanarSrf command we need to create a surface:
With Circle command we need to create one Circle in Right viewport with 7 units as radius. You can either use Offset to offset that circle by 1 units towards inside, or just use Circle command again and create another circle with 6 units as radius.
These two circles need to be projected onto the planar surface we created earlier, so using Project command do just that. Note: from the same (Right) viewport.
Then, using Split command, split the surface with two projected circles, and delete the inner ring surface part. We don’t need it anymore:
Using the Move command, and Snap option enabled, move the inner surface out by 1 unit:
Now, with BlendSrf command we need to blend the two surfaces:
For the next step we need to create some circles to make holes with. So, with Circle command create four circles 0.6 units in radius, and the bottom curve will be 1.6 units outer radius, and for the inner one we will use 1.2 units. The two radii will be then blend with BlendCrv command. Don’t forget to use Snap to make this easier for you.
Using OffsetSrf command we need to make this plate thicker. So, when you start the OffsetSrf command, make sure you click on Solid option, and input the 0.1 for distance. There, you will probably get duplicate surfaces for some reason, but you need to clean that up. You can see in the video version of this tutorial how exactly.
Ok, we can now start making the holes. Using MakeHole command, create the holes out of the circles we previously made:
To make the edges nicer, and specially in render, you can fillet the edges with 0.05 units as radius. ,
Using Circle command create two circles on the top hole position. Do this from Right viewport also, and have Snap turned on, and use 0.5 and 0.3 as radii.
Extrude the bigger circle by 1.2 units, and the smaller one in the opposite way like on the image below:
Using Cylinder command we need to create one small cylinder with the same height as the little screw, 1.2 units. The radius of the cylinder is 0.04 units.
Using ArrayPolar command make 32 instances of this little cylinder around the screw:
Next thing would be to join those surfaces together with BooleanUnion command. Then, using Sphere command, create one sphere with 1 unit as radius and position it in the center of the screw looking from Right viewport, and move it a bit to the right from either top or front viewport. To do that small move, turn off the Snap option.
Using BooleanDifference command you need to get something like on the image 22, but before you do, you need to cut the sphere into half so you can flip the normals.
Repeat the same process for the other butterfly screw.
Using FilletEdge we will fillet the edge with 0.05 as radius:
Using PolyLine and Line command, create lines like on the image 25:
Using Trim command, trim off the parts we don’t need:
Using Fillet command, fillet the corners with 0.2 and 1.0 as radii. For the sharper corners use 0.2, and for the other two use 1.0:
Now, using ExtrudeCrv command, and Option BothSides, extrude the curve by 0.1 units, having it 0.2 units in total, both sides. Using that polysurface, with BooleanDifference we will cut our screw:
Now, again, extrude the curve, this time by 0.08 units, so we’ll have 0.16 in total with bothsides option. Again, using FilletEdge command, fillet the edges with 0.05 as radius:
Using Circle command, create one circle of radius 0.1 units from top viewport, and position it like on the image 30. Using Mirror command, mirror the circle down as well:
Using MakeHole command, create a hole through both surfaces:
Using FilletEdge fillet the edges on top and bottom side of hole with 0.05 units.
Using ExtrudeCrv extrude either top or bottom circle and use the other circle to snap to when defining the extrusion distance.
Again, using FilletEdge, fillet the edges of this extruded polysurface. And using Copy command, copy those two screws one more time and position them like on the image 34. If you use Snap you will easily snap them on their place.
Next thing would be to work on the body of our clock just a bit to get the front panel done right.