Ingenieria

Before starting this tutorial you will need to download two model files, Contor_mould.prt and Contor_material.prt. These parts can be downloaded from the internet and can be found at http://www.staffs.ac.uk/~entdgc/tutorials.htm. Use Netscape to access this and shift+click on the link to download it.

This tutorial is based on a similar Solid model to Tutorial 13 - Intermediate Machiningin Pro/Engineer. Where the difference between the two models is the 10-degree Draft angle applied to the internal walls of the cavity. In engineering practice a draft angle is applied to the walls of a mould to ensure that the product created by the mould’s profile can be removed easily.

The Tutorial objectives are:
To Assemble the design model to a previously generated Workpiece (the partrepresenting material stock) to the design model
Recap the Operation set up and Co-ordinate system creation.
Machine the mould cavity using Contour Surface milling
Simulate the movement of the tool chuck.
Reorder an NC sequence

The first step is to create a new manufacturing file. FILE ( NEW ( MANUFACTURING and NC ASSEMBLY, type in a file name such as Contor_mill. This creates a fileinto which the parts downloaded from the net are to be assembled and the design model is to be machined.
[pic]
Figure1. New Part Menu
The first data to be inserted into the file is the model to be machine. This is specified by the command, MFG MODEL ( ASSEMBLE ( REF MODEL, select the part Contor_mould.prt, DONE ( DONE/RETURN. The current model will be displayed
[pic]
Figure2. Ref.model(Design model)


The second piece of data to be inserted into the file is the Workpiece (stock material) form which the design model is to be machined. The Worpiece has previously been created around the assembled design model, in this exercise the Workpiece has already been created and needs to be assembled, “Constrained” to the part Contor_mould.prt.

The method ofconstraining the Workpiece to the design model is exactly the same as adding constraints to a part in an assemble file, where in this case the assembly is been created within the manfuacturing file instead of a separate assembly file. To assemble the Workpiece, MFG MODEL ( ASSEMBLE ( WORKPIECE, select Contor_material.prt and the familiar assembly constrains box will appear. Add the followingconstraints: 1.Align surface A with A1, 2.Align Surface B with B1, 3.Align Surface C with C1 (the flat top surface of the model)
[pic]
Figure 3. Assembly Constraints
When the constraint dialogue box reads “ Fully constrained” select OK from the constraints box DONE/RETURN. The Workpiece will now be illustrated in a green wire frame as in previous tutorials.
Before and machiningsequences can be created the type of machine and machine setup has to be defined. Since all the machining it done on a single milling machine only one Operation has to be defined. MACHINING ( OPERATION, ensure that Name, Workcell, March sys, Coments, Retract and Active are ticked, DONE OPER.

NAME: type in Milling

WORKCELL: Select CREATE ( MILL ( 3-AXIS ( DONE ( DONE.

MARCH SYS: Thisis a brief recap of the method to follw to create a co-ordinate system for the machining tool paths. Select CREATE, select the Workpiece, 3 PLANE ( DONE. Now select the three external surfaces that create the left-hand corner of the Workpiece. Three arrows will be displayed at the intersection of the left-hand corner. Position the yellow arrows correctly using the NEXT, PREVIOUS and REVERSEoptions. Then assign an axis to the arrows.


REMEMBER IT IS IMPORTNANT TO DEFINE THE VERTICAL ARROW AS THE Z-AXIS.
[pic]

Figure 4. The Co-ordinate System



COMMENTS: Type in “ Operation set up to machine the cavity using 3-axis milling”


RETRACT: Select type in 20



DONE OPER



Now that the Operation (machine setup) has been defined The...