Week 10-Working on the Sphere

I hope to finish the modelling this week so this last file can be combined with the others and the project can hopefully be completed next week.

This week I began by creating the cylinder to represent the pin which went through the central post under the sphere. I set the radius to 0.442cm as I felt this was a realistic width and the height to 10.49cm so that a little of the cylinder was visible either side of the lever.

Next I went on to create the part which attaches to the side of the lever, once again starting with a cylinder. I used the move and rotate tools to position this at the correct angle before creating a third cylinder, but this time smaller in height and with a larger radius of 1.197cm.

I then made the most recent cylinder into an editable poly, went into polygon mode and highlighted several of the segments along the bottom edge. I then opened the extrude window and repeatedly extruded these polygons to an amount of 1.396cm until it reached the height I required. I then transferred to vertex mode and with the use of the move and rotate tools created the bend in this shape.

Afterwards I drew out a new cylinder where I increased the height segment value to 3. I then made it into an editable poly and deleted the unnecessary polygons at the back of the shape. This left me with space to create the shape I required which I did with the create tool. Whilst still in polygon mode I drew around the open edged vertexes to recreate the shape as I required it to be. Firstly I created the segments at the back and then the ones on the inside of the shape.

Once this shape was complete I came out of editable poly mode and used the rotate tool to position it at the correct angle.

I then returned to editable poly mode and in edge mode used the cut tool to segment the cap. I sliced the polygon in many segments by dragging the dividing line between two points which were opposite one another.

Following this I selected the edges I had just created and opened the connect edges window. Here I added one extra segment so the cap was divided into two rings of polygons.

At this point I realised errors had been made when cutting the polygons and so used the weld tool to join two vertexes which should be one.

I then highlighted the polygons which made up the smaller ring before opening the extrude window. I applied an extrude value many times, each time changing the height of extrusion so it represented the height of the area I was trying to create.

Whilst doing this I realised that one half of this rod was a mirror image of the other, and so worked to the half way point where I applied the symmetry modifier. Once the symmetry modifier was applied I used the mirror property in its rollout to position the symmetrical part correctly in relation to the first. This took some time to perfect, but eventually I was happy with this.

Next I went on to create the bolts along the joining rod, and as before I did this in editable polys vertex mode. I then used the scale tool to make the bolt area larger than the rest of the cylinder. However, when I was doing this I found it would not scale properly due to the angle the rod was positioned at and so I removed the rotation I had previously applied before completing this task. When I then tried to create the bolts the outcome was that the sections were much more even.

Finally I reapplied the rotation.

After this I went on to create the part which joins onto the box part of the steam engine. For this I started by creating a box and segmenting it 5 times along the length and 3 along the width. I then made it into an editable poly and scaled the vertexes which made up the segments apart before scaling the vertexes which made up the top and bottom row to create a curved outer edge.

Next I created a cylinder with a radius of 0.722cm as this fitted nicely into the box shape just created. I then created an array of these at 1.7cm apart.

Next I selected the edited box and from the compound objects section of the create menu selected Boolean. Here I selected subtraction (A-B) from the list to create a hole were the cylinders was. I then repeated this for the other cylinders.

I then created the part which joins the rod to the box of the machine. For this I started with a cylinder which had a radius equal to the width of the top of the Boolean box and positioned it here. I set the cap segment value to 2 to make it easier to work with.

Next I made it into an editable poly, went to polygon mode and highlighted the segments in the middle of each cap. I then extruded both sides at the same time to a rough amount before perfecting the height of each extruded section with the move tool in vertex mode.

I added the finishing touches by adding the pins to either end of the rod to give the illusion they were joined. I positioned the cylinder which made the pins carefully so they were in the middle of the end segment of the rod.

The modelling was now complete and so I applied a mesh smooth; however this did not smooth the shapes as I required it to. To correct this I made alterations to smoothing group setting on necessary objects in polygon mode and set the mesh smooth to pay attention to the smoothing group settings. As before when I wanted a surface to be smooth I applied one smoothing group value to the whole area but when I wanted there to be an obvious join I used two different smoothing group values. Below is the model with the mesh smooth modifier and smoothing groups applied. Some areas were difficult to do, such as the top of the area extruded out of the top of the sphere, as it took a while to work out which parts should belong to which smoothing group.

The modelling of the engine is now complete. Next week I hope to complete my part of the animation.