It is hard to believe that it was only seven years ago I witnessed a CNC router in action for the very first time. I was fascinated and simply had to have one! Although I had been in the creative end of the three dimensional sign business for most of my life I didn't really know what I would do with one - but I just knew it could do fantastic stuff.

Through extensive research I quickly found out that with the relative simplicity of EnRoute, CNC routers were capable of just about anything imaginable. This journal will chronicle that journey to date and continue each week with two or three entries as we continue to explore just what is possible with this wonderful software... -dan

Monday, May 4, 2015

Mine car wheels (Revisited)

About three years ago I started a demo sign project that featured a mine and mining car. Just about then we got really busy and it languished until last year. Then I used the parts to create a little mining car that became the weather vane for the water tower of the Cultus Lake Adventure Park.

Now with the addition of the Runaway mine train I needed another set of mine car wheels. I didn't have to start from scratch for it was a simple matter of reopening the saved file and enlarging them to suit the slightly larger scale current project. They are five inches in diameter this go around.

I'll be referencing the assembly of the car and sign in the next post so I thought I would repost the wheel creation again for this one.

The wheels of the little mine car are a great exercise to practice our building of various shaped reliefs and how to merge them into a final shape which we want. As we build the reliefs we have to keep in mind the final result and then think of what we have to add or take away to get exactly that. There are many ways we could have achieved a similar effect.

We start with the vectors of course - all created inside EnRoute. The wheel will be four inches in diameter (including the flange) and 1" deep.

The back flanges on railway wheels are sloped so the first task was to create a disk using the largest vector circle.  I kept it fairly shallow.

Then I selected the next vector and created a flat disk 0.9" tall. This was then merged with the first tapered disk I created.

Then it was time to knock out the center to make room for the spokes and the hub of the wheel. I created a zero height relief which was then merged to the base relief.

Next up was the spokes. I first created flat reliefs in the shape of the spokes.

The spokes looked good but I wanted them to be curved on top and higher in the center. THis would need to be done in a couple of moved by modifying these reliefs. First ‘I used the done tool to puch down the center in a bowl shape.

Then I used the prism tool to modify the reliefs once more by building them over a cone shape.

These spokes were them merged highest with the base relief.

Next up was the hub of the wheel. I created a flat relief 0.9" tall. This was then merged (replace) with the base relief.

The last step was to add the center section of the hub by adding to the relief.

I then duplicated the wheel to make a set of four. This was tool pathed using a 3/8" ball nose bit for a rough pass at a 50% overlap. A final pass was then added using a 1/8" tapered ball nose bit with an 80% overlap. I'll post some pictures as soon as I put the file on the MultiCam. It will be routed from 1" 30 lb Precision Board.

Stay tuned...