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

Wednesday, March 14, 2012

The key to merging

Today I spent my time teaching a relative newcomer to EnRoute the ins and outs of merging reliefs. Like many he found the concept of merging reliefs somewhat hard to grasp. There are four options but today I will deal with two - merge highest and merge lowest. After some simple exercises and lots of trial and error it was time for a real file - a KEY. It would employ both merge highest and merge lowest as well as some other tasks. The file was in fact harder than it looked at first glance. While certain pieces could have been done with sweep to rails I was trying to keep things simple... or at least as simple as possible for this exercise. The key we were modeling had two key ways cut into it at different depth. Both were cut with a circular grinding wheel and so were rounded upwards at the big end of the key. That was the difficult part.

The vectors were relatively easy - all done in EnRoute.

The first relief I created was for the key ways. I would model the key at two inches thick and thin it down later. Since I wanted the key way to go half way into the key it needed to be one inch deep and ramp up at the end. By using the scale to height on the rounded relief I could control this. Take note I used the subtract from relief command to make it go down.

To create the flat portions of the key I created two rectangles which would be used to create flat reliefs two inches high (The same height as the key)

In this screen shot (front view) you can see the thin grey line is the top of the flat reliefs while the bowl we created is well below. I would use the up key to nudge it upwards until it was even with the two inch high flat reliefs.

Then it was time to use the MERGE HIGHEST command to merge the flat reliefs to the key way bowl.

The result (after I deleted the no longer needed rectangle reliefs) looked like this. 

Then it was time to create the key relief. This was done as a two inch high flat relief in the shape of a key.

To match the sample I modified the key relief with three grooves across the head using the bevel tool and the subtract from relief command.

Then it was time to use the MERGE LOWEST command. I would be modifying the key relief by using the keyway bowl with the two inch high vectors (previously merged highest to it.)

 Now we had a good looking key.

The last step was to use the narrow keyway profile to modify the key shaped relief. I positioned the relief correctly then stretched the modifying relief down a bit. I again used the MERGE LOWEST COMMAND to modify the key shaped relief.

The result was a good looking key. But we were not finished yet.

Since I had modeled the key at two inches think it didn't look at all proper. 

In the front view I simply grabbed a top node and shrunk it down to size. PRESTO - perfect key.

So there you have it... the key to learning MERGE HIGHEST and MERGE LOWEST.  Give it a whirl and I hope this helps!