Manual Preview - How it all works

THE MODEL:

Making large patterns with the e-motion system.

A model of the item to be produced has to be generated usually as a solid or a surface model in a CAD system. A solid model is generated in a 3d modelling package such as 'Rhinoceros'. Rhino has a very intuitive interface and is probably the quickest and easiest of all the modelling packages to learn and best for producing freeform shapes.

(Models can be supplied from other people and can be machined without necessarily having to generate the model yourself.)

THE TOOL PATH:

The cutting tool is guided by a file of line co-ordinates which is produced by a toolpath program.
The model is exported from CAD as an IGES file and can then be imported to a toolpath program. It is desirable to use a toolpath program which is NURBS based. What this means is that the toolpath contours are likely to be smoother than the contours created from a program which uses a source file based on triangles.
Most Cad systems will output an IGES file and this enables the system to operate on data which may have been created elsewhere.
Toolpathing is where the machining strategy is worked out and this can be very simple or can require some experience depending on the complexity of the model.
Commonly, the tool used for machining is a ball end tool. When it machines over the stock the finish is better on a double curvature surface. The closeness of the slices that are cut dictates the surface finish and how long it takes to cut.

In the toolpath software the tool is specified and the type of path is also specified. Consider for example a spherical shape which will require TWO styles of path applied sequentially. This shape may be machined firstly with a path that is z level waterlines where the path steps vertically. On the near-vertical part of the sphere the surface produced will be excellent due to the closeness of the cut lines. As the surface becomes more horizontal the cut lines gradually become much further apart on X and Y axes and so the surface quality deteriorates. This situation will require a second toolpath to be prepared which is perhaps a planar path that is done on the top of the sphere to get a better finish. With planar cutting the path steps horizontally either along the x or y axis or even at a specified angle to x or y.

Usually a roughing path is specified first to bring the stock down to a shape that is close to the finished size and then the finish cuts are applied.
Once the toolpath(s) are created they are exported to the working directory of the user interface.

THE MACHINING - with the 3D-e-Motion USER INTERFACE

The machining operation is quite intuitive.

A simple glossary of terms used on your computer screen needs to be learnt and of course an understanding of xyz axes.

3D-e Motion is started by clicking with your mouse on the 3D-e Motion icon which we have setup on your computer desktop.
3D-e-Motion user interface has two screens.
The table screen which gives access to files and enables the machine to be made ready for operation.
The cutting screen - which comes into action when the machine is in operation. This screen gives a full graphic picture of the operation in progress and the display can be rotated, panned and scaled. Co-ordinate position of the tool and the line number within the file are continuously displayed.
The toolpaths need to be converted into a language that the machine will understand. This is done by following the prompts under the command "make cut file".
At this stage the machine is moved to table home - this is where the minimum x-axis position and the minimum y axis positions are. The z axis is also homed to its maximum height.
The stock is now placed on the table making sure that it is in a position that enables the tool to access it without exceeding the table limits. (If it won't work software will tell you with a warning message)
Now the tool is moved under manual control to a job home position which usually is the same as the x=0,y=0,z=0 position on the original solid model drawing.

Example - to move the tool in an x positive direction press "x" on keyboard then, following the prompt that appears, give the direction (either plus or minus) and then give a distance (in mm). Finally activate the move command - either jog or walk. If jog is selected the tool will move at maximum speed to position but if walk is selected the operator can dictate a slower speed (in metres per minute).

Once the tool is in the correct looking position activate the command "make current position job home". - the coordinates displayed will reset to zero and on the left of the screen will be a listing of the xyz position from table home which we originally set. This is called a "relative machining system" as against an absolute system where the job would have had to be drawn in the actual position on the machine where it is to be machined.
Now we load the first cut file that was prepared - probably a roughing cut. ("new job")
Activate the command "cut file" and the software will go to the cutting screen.
You have an option to do a dry run where the machine does not move - you just get a graphic display of the toolpath being followed and you can change the size and rotation angle of the display to suit what will tell you the most when the machine is actually running.
The dry run will also indicate if there is a mistake in the file itself and is a good safety move to carry out.
Happy with all this now it is ok to run the machine in anger.
Speed of machining will start at default speed which is displayed at the bottom left of the cutting screen. Speed can be slowed by turning the speed knob with each left hand turn cutting the speed in half. Or speed can be increased with the mouse by clicking on "faster" until you have a speed which suits. You are still able to decrease speed with the speed knob. It is quite good to use the mouse to set a speed which is one click back from maximum required then as the job progresses you can vary the speed to suit as the job progresses.
If it is desired to stop during machining the "esc" key will cause the cutting to stop at the end of the current contour. Alternatively the emergency stop button will cause immediate stoppage which is reversible with another press of the emergency button.
With an esc stop you can send the tool to home or can continue cutting.
With an emergency stop you can continue cutting but cannot send the tool home without restarting and then pressing the esc function.
If you have to abandon the job after an emergency stop you can crash out of the software and restart the program then do your repair or whatever and when you go back into the cut job function you will have the option to continue at the same position where the job was stopped.