Region curves vs extruded curve

It's a common thought that the Region curves function is a "hard" boundary that the cutter can't leave. This is a negative assumption. The region curve tells the tool path generator where to cut the model, it doesn't fence the cutter in that area. There is a simple way to make a fenced area with an extruded curve, for example the region curve itself. This will cause the cutter to stay inside the region. Here is a simple example:

Tip! Make a region curve, expand it with a bit more than the cutter radius. Make an extruded curve with the new expanded curve and then use the the smaller curve for the region. Doing it this way the tool path will not climb the wall, it will go directly to the model surface. Here is a bit more sophisticated version, yet simple though:

Toolpath Array

How to make an arrayed toolpath in MadCam. You need to make a Group Repair to reconnect the new paths with the original path.

This clip is available in HD. Maximize the video screen and increase the resolution and you'll have a crisp clear view. As usual, I run this demo in a virtual environment and it makes the simulator acting a bit odd. Try it for real!

Making a mirrored toolpath

There are two ways to do a mirrored copy of a toolpath in MadCAM. Either you make a copy of the toolpath and rotate/move the copy into the new position, OR you do a mirror command and then Group repair. When doing a mirror of the toolpath MadCAM looses the reference to the start point for the new path, but that's an easy fix with the Group Repair command. To see the the new path in the simulator you have to reselect all the parts.

This clip is available in HD. Maximize the video screen and increase the resolution and you'll have a crisp clear view. As usual, I run this demo in a virtual environment and it makes the simulator acting a bit odd. Try it for real!

Making regions

Here are a few simple examples how regions will help you to restrict the working area for a toolpath. Note that if you want to make a roughing or Z-level and a lot of "islands" it's better time wise to generate a toolpath for each region instead of selecting multiple regions. In that way the toolpath will finish one region and then move to next. When a group of regions are used to make a rough/Z-level each level will be finished in every region and therefore a lot of extra movement will be added. On a small model it's not a problem, when doing batches or uge moulds it will take more time. When all regions are generated, make all wanted toolpaths visible and post process them into one program.

This clip is available in HD. Maximize the video screen and increase the resolution and you'll have a crisp clear view.

Colourized simulation and making a different stock

In the latest release of MadCAM (4.3) the simulator makes every toolpath cut in a colour, which give a very nice visualization where the cutter really made a cut. It's easy to add or change the cutter colours. Here's how. I also modify the stock model to show the difference in the toolpath when the stock is changed with the options "Enclose", "Model + Cutter" and defining a true stock model.

This clip is available in HD. Maximize the video screen and increase the resolution and you'll have a crisp clear view.

Moving around in space

If a model is generated in one place, but you need to mill it at another position in your machine, just move the model and all the toolpaths and go!
Toolpaths in MadCAM can be moved, rotated, duplicated as any other Rhino object. It isn't until the post processing that the toolpath coordinates will be saved. If you post process and move or duplicate the toolpaths afterwards you only need to post process again to get the correct machine program.

Axle mount

This is a support for two shafts. It's an easy task to make it and it only need some pocketing and profiling.

1. First I rearrange the model and some curves to find them easier. I also copy the profile and remove the inner pocketing to get a closed curve for the outer profile only.
2. Select the model and define the work piece.
3. Select a cutter.
4. Go to the 2.5D menu and select pocketing, selecting the top edge of the big pocket. In the dialog the cutting is set to Relative (see Options) and therefore we cut from 0 which is relative to the selected line and the cut -20 mm. We'll use 1 mm Break Through to get a nice edge in the bottom.
5. The 2.5D Pocketing is once again selected to make the small pocket, but this time I use the bottom edge to show the difference once again for the relative setting in the Pocketing dialog. Therefore we'll now go 20 mm from the edge curve and then to zero.
6. Hide the model to show the outer profile. Go to 2.5D->Profiling, select the curve.
7. I choose to leave a skin in the bottom to ensure that the piece will stay and not move around and be damaged by the mill.
8. Now, I OK'd the dialog without checking which side I should cut of the curve. I got an inner side profiling which is totally wrong. But no problem! Just delete the non wanted layer and rerun the dialog!
9. Check the Simulator, Post process and go.

The 2.5D-tutorial refreshed

The sharp eyed noticed that the machining time in the 2.5D-tutorial example was very long, and I would say it's not a realistic example either for a pro workshop. This is how you the pocketing would be done to speed up the tempo. Of course it's a matter of tool changes. In an industrial environment that's not a problem though.

First of, there's a roughing made with a bigger end mill, leaving a tiny bit of material.

Then we go fine pocketing with the small mill, getting better corners and vertical finish.

The machining time is now less than half with a simple change in the milling strategy.

The 2.5D-tutorial

Once upon a time I started to write a 2D tutorial, but it takes awful a lot of time so it's actually not ready yet. It's thousand times faster to create videos...

This is the 2D tutorial exerpt that is published at the MadCAM website but in video format!

Hiding tool paths

Every new tool path created will occur in a new layer. There can be many tool paths at the same time, but you might want to run only a few of them. For example if you create paths for different machines or different cutters. In this example I've made a holder for a dampener, it uses a ball cutter and a flat cutter.

As you can see there are multiple path layers. Let's disable or enable a few of them and see what happens in the simulator. What happens in the simulator is what you get when you post process (WYSIWYG).

2D Pocketing with islands

This is a continual post of the 2D Contouring.

So, what if my pocket contains islands? No problem, just select the island's edges at the same time as you define the pocketing curve and they will be protected.

I added a center axle on the extender model as an example.

1. Workpiece and cutter is already defined, so I go directly to 2D Icon-Pocketing.
2. I select the pocket edge and the axle (island) edge and press enter when ready (or right mouse click, which is standard in Rhino).
3. I use the same setting as before, just go for it.
4. Now in the simulator, I see my center axle preserved.

Making an extender with 2D contouring

Here's an extender for a musician's instrument. It's 85 mm in diameter. It's going to be cut out from a bigger 20 mm piece, so I only need the contouring.

I'm going to show the differences for some of the basic options for 2D contouring.

1. First select the model and click the first icon in the MadCAM toolbar to get the workpiece defined.
2. Then click the cutter icon to open the cutter library. This time a 10 mm flat cutter is selected.
3. Select 2D path->Pocketing. Then the surface edge for the hole is selected. The Contouring dialog appears.
4. Here I show the difference between Depth From Curve and Depth Absolute. When using From Curve, the cutting depth will start from the curve as zero and then go relative, I have to define the depth as -20. When using Absolute the cutting starts at Z 20 mm and ends at Z 0. The Z value will be filled in automagically when the Material Top field is double clicked.
5. I set the Step Down value to 2 mm for 2 mm cuts at a time, Skin Cut and Break Through is set to zero.
6. When everything is OK, the toolpath will be generated in a new layer.

Now the contouring is ready, but what's the difference between Skin Cut and Break Through?

1. Delete the new layer.
2. Once again go to 2D path icon->Pocketing and click on the surface edge of the hole.
3. Skin Cut, defines how much of the depth of the material that should stay. This is perfect when pieces are milled out from a sheet and they should stay with the rest of the material instead of been catapulted by the mill. Here I define 5 mm just to clearly show what happens with the toolpath, which now stops at Z 5 mm.
4. Next I go back to the 2D Contouring and define a Break Through instead. Now the toolpath is passing Z 0 mm to -5 instead. This is useful for example when a piece later will be cut of or if the bottom will be filled up with another material (like a isolating layer etc).

Ok, the hole toolpath is re-generated. I know make a Profiling for the outer edge, still 2 mm Step Down but I leave 0.1 mm Skin Cut to avoid have a loose piece when it's finally milled. The Direction (just outside the movie clip window...) is set to Outer.

Everything is tested in the Simulator.

And by the way, the musician is the stunning drummer Petter Berndalen. 

How to find your MadCAM version

Sometimes you need to figure out your installed version of MadCAM. This is how you do it.

1. Start Rhino 3D
2. In the command line, type madcamcommand and hit Enter, Madcam will load.
3. Now type version and hit Enter.

You should now have a dialog in front of you specifying the version you have.