![]() ![]() We then described our funnel shape as the second element of this operation in order to subtract it from the main body. Inside the module, we made the definition of our wall anchor shape the first element of a Boolean difference operation. The position is specified relative to the length of the anchor. The parameter inner_taper_end sets the position where the neck of our funnel shape starts. The parameter inner_taper sets the taper factor of the inner diameter and determines how thin the neck of our funnel shape becomes. We have added two more parameters to our module. Inner_taper_end = 0.3, // relative end of inner taper along lengthĪbs_taper_end = length * inner_taper_end Ĭylinder( d1 = screw_dm, d2 = taper_dm, h = abs_taper_end + 0.01) Ĭylinder( d = taper_dm, h = length - abs_taper_end + 0.02 ) We can make this funnel shape with two cylinders and subtract both from our main body using a Boolean difference operation: ![]() Then it tapers so that the screw can push the sides of the anchor apart and press them against the inside of the hole. At the beginning, the hole in the anchor has the diameter of the screw. The cavity inside our wall anchor, i.e., the hole in which we screw in the screw, has the shape of a funnel. The parameter oversize is used in the calculation of side_length. So with the help of this parameter we can very easily describe the desired taper of the wall anchor. The transformation linear_extrude offers a parameter scale, with which we can reduce or enlarge the 2D shape along the extrusion path. Linear_extrude( height = length, scale = outer_taper ) Side_length = sqrt( pow(outer_dm, 2) / 2 ) Outer_taper = 0.75, // outer taper factor As we implement the taper in our geometry description we can now benefit from our decision to use a combination of square and linear_extrude instead of using a cube: Thus, the parameter has to be changed only if this default value does not lead to a good result. Using a taper factor allows to give the parameter a reasonable default value that links the resulting taper to the borehole diameter. However, this would mean that you always have to specify this diameter, since it has to be selected to match the borehole diameter. Instead of a factor one could also consider specifying a “target diameter”. The parameter outer_taper is a taper factor that makes the wall anchor thinner towards the end. The parameter oversize will be added to the drill diameter. We add two new parameters that will allow us to adjust our wall anchor in this regard as needed. Therefore, we want the basic shape of our anchor to be wedge-shaped. We will see the benefit of this approach in the next step.Īs mentioned above, our wall anchor should also work in “difficult” drill holes that have become larger than planned due to the drill wandering. Instead, we use its two-dimensional counterpart square and then transform the 2D shape into a 3D object by using linear_extrude. ![]() In this project we do not use the 3D basic shape cube to describe the body of the wall anchor. To get a, we only have to take the square root: a = sqrt( c^2 / 2 ). If we now move the 2 to the other side of the equation, we are almost done: a^2 = c^2 / 2. So we can rewrite our formula to a^2 + a^2 = c^2 or 2 x a^2 = c^2. Since our triangle is in a square, we already know that the small sides are equal in length. In our particular case here, the long side of the triangle c is given and we are looking for the length of the small sides. ![]() We know that a^2 + b^2 = c^2 holds true in a right triangle. Side_length = sqrt( pow(drill_hole_dm, 2) / 2 ) ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |