Manufacturing with Pro/Engineer Wildfire

Carnegie Mellon University Mechanical Engineering

Updated November 2, 2010 by Gary Verma and Wei Guo

Introduction This is the final tutorial in the wrench project. When you have completed this tutorial,

you will have generated a file that the computer-controlled mill can use to make your unique wrench. Before you create that file, however, you must add text to personalize your wrench. We did not include the text until now because it would have needlessly complicated the analysis from the previous section. After you have modified your wrench, you must tell pro/Engineer what type of machine it is creating a file for, define the blank from which the wrench will be cut and the tooling, and then create the path the tool will take. Finally, you will translate the output into the mill's native file format and send the finished product to the shop.

Setup Unlike the previous tutorials, this one requires some files we have made beforehand. These include a model for the aluminum blank you made in the shop, the mill and the cutters. You will need to save these files to c:\temp. Right-click on the zip file below and select Save Target As..., then save to c:\temp. Unzip the file and there are 8 files contained in this zip file. Make sure to move all 8 files to c:\temp.

Manufacturing.zip You will also need to use an FTP program to copy your wrench to c:\temp. Click here to open a tutorial on using WS-FTP if you do not know how.

Adding text to the wrench handle The first thing we need to do is add the writing on the front face of the wrench. We have not included it to this point because it has negligible effects on the strength of the wrench. In general, one should analyze the simplest problem that will yield a correct solution.

Procedure: Start Start ProE Wildfire from Start - All Programs -> PTC > Pro Engineer > Pro Engineer

The first window that should come up if new user is shown below:

Browse through to directory you want to be startup directory, for example My Documents. The program should take some time to load after doing this.

Once that is done, the working directory must be changed. Go to File -> Set Working Directory, and choose the directory where your wrench file has been saved.

Select Ok. Then load up the wrench file by selecting File Open and selecting the model.

Once loaded, reorient your view to the Standard Orientation. This is found in View Orientation Standard Orientation, or press Ctrl+D as a shortcut.

Next we will be adding the text of the writing. Text is added as a groove feature, so we can use an engraving machining operation later on.

From the top menu select Insert Cosmetic Groove.

This will bring up the select window.

Click on the top face of the wrench. If properly selected, the top face will turn red and look like below. When it does, click OK

Next click Done Refs In the Menu Manager window.

Manu manager will change to the following screen.

Select Use Prev and click Okay. The screen will change back to the sketch view. Your screen should look like the following:

Select the Create text as part of a section button .

Click once on the bottom left portion of the handle, then move the mouse vertically upwards to create a vertical line. When you reach the upper left quadrant, click again. This step does not have to be exact.

If you receive an error message asking if the selected entities should be aligned, click No.

Otherwise, the following window will appear.

You may add any text you wish, up to a maximum of approximately 10 characters. The example will be adding the text Engineer to this particular wrench. Type your text into the box. As you are typing, the text will appear on your wrench. If your text looks approximately like the following, youre okay. Click Ok.

The text should now be dimensioned. This is often easier to do by changing the grey weak dimensions than by creating new ones like we did in the first tutorial.

Click the Select Items button on the right side toolbar to make the dimensions of the text entered appear. Double click the grey horizontal dimension below the text. A text box will appear as shown below.

Change that dimension to 1.5 inches and hit enter.

There are two more grey dimensions. One is the height of the letters, the other is the distance the letters are from the centerline. Change the smaller dimension to .25 and the larger to .5, then zoom out. Your wrench should look like the following.

Play with the text until you are happy with the placement and are sure the text extends no more than 1.5 inches on either side.

When you are happy with your text and placement, click the Continue With Current Selection

button from the right toolbar.

Your wrench should look similar to the following (with your text). If it does, save it and continue on. If not, contact the TA.

Attaching the wrench to the workpiece

The wrench you have created will be cut from a blank of aluminum that you made in the

machine shop. We must tell the program the size and shape of that blank, so that it knows how much material must be removed. We must load this blank and place your wrench in the center of it. We now need to make a manufacturing file. Press the Create a New Object button on the top

toolbar . From the screen that appears, select Manufacturing from Type and NC Assembly from sub-type. Enter your group number in the Name field and press OK. It may take a minute for the manufacturing portion of Pro/Engineer to load.

Once loaded, select the Assemble Reference Model button . This will load the wrench into the manufacturing file.

When the Open window appears, find your wrench file and click the Open button as shown below.

In the constraints menu at the top, change Automatic to Default in the drop down menu. Click the green check mark.

Next we must load and assemble the workpiece. The workpiece represents the blank from which the wrench will be cut. Click the Assemble Workpiece button

This will bring up the Open window. Locate and select Blank.prt from the attached parts folder provided as shown below, then click the Open button.

.

When the workpiece loads your view should look like the following.

Now we must move the workpiece so that the model is contained inside it. To do this we set a constraint as follows: In the Constraints menu at the top, select Placement Select the green box that says Select component item. In the Constraint Type dropdown, select Coord Sys as shown below.

Next we must select the coordinate system of the workpiece. Click on PRT_Csys_Def inside the blank as shown below. Make sure not to select the text that begins with MILL_CS, as it overlaps with what should actually be selected.

Next select the green box that says Select assembly item. Click the Placement tab to hide it and move the cursor to the left side parts tree. Select the plus next to the wrench part name.

Select PRT_CSYS_DEF The workpiece will move to cover the wrench. The part should look as shown below:

When it does click the green checkmark on the top right.

The next thing we need to do is make sure that the engraving bit that writes your text will not impact the mounting bolts that keep the blank fastened to the mill while it is being machined.

From the top toolbar select Hidden Line view . Your wrench should change to look like the following image.

The green lines represents the workpiece while the white represent the reference model. The holes in the green part are mounting holes that hold your workpiece to the mill. These must not be touching or overlapping your text or your wrench will not machine properly, and it will break the mill's cutter. If your text does not touch the green mounting holes, proceed to the next step. If it does, contact the TA immediately or reformat your text to be smaller.

Defining the mill parameters and making the rough cut We must now create a representation of the machine shop's mill. We also need to tell the mill what speed to turn the cutter, how fast to travel, and other parameters. These rates are determined by a number of factors and have been packaged into parameter files for you. You must, however, tell the program which set of parameters to use for different operations. For example, the mill turns faster with the .125 inch bit that writes your text than it does with the half inch bit that cuts out the bulk of the material. Next we must define the machine which will be doing the cutting. From the top menu, select Steps Operation

This will bring up the Operation Setup window. The first thing we need to do is name the machining operation. Name your operation Firstname_Lastname_MFG as shown

. Next we will load machine data for the mill we will be using. Click the Open Machine Tool icon

The Machine Tool Setup window will open.

Click the Retrieve Machine button and load HAAS_Mill.Gph located in the folder of models given. Select Ok.

Next we need to give the mill a reference point from which to machine the wrench. In the Reference box of the Operation Setup window, click the arrow.

This should bring up the Menu Manager:

Now we must select a coordinate system for the mill. There are multiple coordinate systems with different orientations at the center now. The one you want is named MILL_CS. When it is highlighted, click on it.

When done correctly, it will create a new coordinate system named NC_MILL_CS which will have the Z axis pointing upwards and X to the right. If it is not, repeat the previous step.

Finally, we must select a retract, which is the position to which the cutter head moves when it is not cutting in order to completely clear the workpiece. Select the arrow in the Retract box, and the Retract Setup window opens.

Click the Along Z Axis button, then enter 1 for depth. This will make the cutter retract one inch above the workpiece when not in use. When your window looks like below, click OK

When your part looks like the image below, click OK to close the Operation Setup window.

Now that the machine is set up properly, we must create the paths which the cutter will follow while machining the wrench. We will be machining using a Profile operation, which is used to cut two dimensional parts from flat blanks by cutting along the edges. From the top menu select Steps Profile Milling

The Menu Manager window will show options for the operation. Select Name, Tool, Parameters, and Machining Surfaces as shown above and uncheck all the rest. This tells the program that you want to name the cut, select what tool to cut with, the speeds and settings and where the cut will be. The other options are not necessary as the ones we already set up are correct for all the operations we will do. When your menu looks like the following, click Done.

We now will enter the data for the operation. The first thing the program asks for is the name. When you clicked Done at the end of last step, a text box appears asking you to name the cut. Name this one RoughCut, because we will be using a large cutter to quickly cut most of the material away. When you have entered the name, click the green check box as shown below.

Next we must tell the mill what cutter to use. The mill has a table of cutters from which it can select the proper one for a particular operation. In this way, the machining time is reduced because the machine does not have to stop between cuts. The Tools Setup screen will appear. If there are already tools present, delete them by selecting them and pressing the red X.

Click the Open button and load t500.tpm from the provided parts folder. This is an end mill half an inch in diameter. When your window looks like the one below, click OK.

Next we must set the Manufacturing Parameters for this cutter. These include the cutter speed, the speed the mill travels, the coolant options and so forth. These are already saved, all you need to do is load them. Click Ok from the Tools Setup window. The following should appear:

Click File Open

Then locate the manufacturing folder provided and select rough.mil. Click Open

Select Ok from the previous window. Next we must select the model which contains the surface information. The Surfaces window should pop up. You must select your wrench model. However, it may be difficult to do that by clicking on the wrench, because the workpiece is coincident with it. Select your wrench by clicking on firstname_lastname.PRT as shown below:

Make sure to select the .PRT file and not the .ASM file.

Your wrench will turn red. When it does, click the green check mark.

Now we must select the surfaces which will be machined. All the edges will be machined in this operation, but not the faces. In the left tree click your part again.

Next we must make sure that the sequence is set up properly. We do this by displaying the cutter head on the screen. Click Play path from the Menu Manager window, as shown below.

Now, check the Compute CL checkbox to have the computer calculate the position of the cutter head and click Screen Play as shown below.

The Play Path window will appear. Click the Play Forward button and you will see an on-screen representation of the cutter path. Your cut should look like the example shown in red below:

Make sure the mill goes all the way through the piece. You can verify this by changing the view by holding down the middle click button and dragging to rotate.

When your screen play is finished and you have verified the path, click Close on the Play Path window and then click Done Seq in the Menu Manager window as shown below to finish the Rough cut.

Creating the finish cut Next we will be making a finish cut on the same surfaces. Because the cutter does not have to remove much material, we can run the mill at a high speed with a small cutter. This will give a very clean appearance to the finished wrench. Again from the top menu, select Steps Profile Milling. Our second operation is exactly like the first, except with a different tool and manufacturing parameters. From the Seq Setup portion of Menu Manager, check Name, Tool, Parameters and Machining Surfaces. When you have selected these four as shown below, click Done.

Again at the top of the screen we must enter a naming operation. Name this FinishCut and select the green checkmark when done.

Now we must load the tool we will be using. The Tools Setup menu should appear and show the previous tool loaded. Using the same technique with which you loaded the half inch end mill, load the quarter inch end mill named t250.tpm. When your Tools Setup window looks like below, click OK to close it.

As with the first one, click File Open when the Edit Parameters window pops up. Locate the manufacturing files folder given, and load finish.mil.

Select Open once finish.mil is located. Say Ok in the previous window. When the Surfaces window appears. Select your model named firstname_lastname.PRT from the left model tree view, and then click the green checkmark.

Click Done/Return to finish the sequence. Next we must play the path to make sure it is correct. Click Play Path in the Menu Manager window, check Compute CL and click Screen Play. Play the tool path like you did for RoughCut. It should look like the image below.

The red line corresponds to the path of the center of the mill and does not trace directly on the outside of the wrench to account for the diameter of the mill.

When you are certain that your FinishCut operation is correct, Close the Play Path window and click Done Seq.

Engraving the text Our last operation is the writing on the face of the wrench. This is not a Profile operation but uses the Engraving type instead. Engraving is used to make shallow passes on a flat face. Engraving follows cosmetic groove features, instead of model geometry. From the top menu, select Steps Engraving

In the Seq Setup portion of the Menu Manager window, check Name, Tool, Parameters and Groove Feat. When you have those four selected, click Done.

The sequence name box will show up again at the top. Type WritingCut. Select the green checkmark.

Next load t125.tpm from the Tools Setup window. t125.tpm is an eighth inch cutter with a rounded end. This creates a wide, readable groove which makes attractive lettering. When your Tools Setup window looks like below, click OK

This will open up the Edit Parameters window. Load writing.mil the same way the other parameters files were open.

Once loaded, select Ok from the previous window. This should bring up a select window to select groove features. You want to select the writing on your wrench by left clicking it as shown below. When highlighting your text, it should turn from yellow to blue. When clicked it should turn red. Click OK in the Select window.

Click Play Path to show the tool path in the same way you did for the last two operations. Again select Compute Cl and click Screen Play.

The animation should show each letter being machined, and the end result should look as follows.

If it does, Close the Play Path window and click Done Seq in the Menu Manager window.

Post-processing the wrench Now we have to tell the program to create code that the CNC mill in the machine shop can read. Select in the left hand tree firstname_lastname_MFG. The process that contains all three cuts you created. Go to Tools CL Data Play Path from the top menu.

This should pop up the Menu Manager. Check mark Compute CL and click Done. This should bring up the simulation setup and PLAY PATH window. Click the play button and verify the path follows the three cuts specified. Verify the final result is as shown:

When you are certain that all three operations are correct, it is time to create a file that the mill can read. Click File Save As on the PLAY PATH window. This should open up the Save a copy window.

Type in a relevant name or just leave the default name in and click OK as shown.

Now we must translate the data from an .ncl file, which is a generic computer control language, to a file that the mill can read directly. Click Close on the PLAY PATH window. Go to Tools CL Data Post Process.

The program will prompt you for a file to post process. Select the file you just created as shown below and click Open.

Next click Done in the Menu Manager window. Select UNCX01.P02 from the list shown in Menu Manager. A black DOS window will appear and prompt you to select a program number. Enter and press the Enter key. A status window showing the results of the post processing operation will appear. Close it. Check the folder your assembly is saved in to see if a .tap file was created. You have completed the manufacturing section of the wrench project. Save your work by selecting File from the top menu and choosing Save. Say Ok when the window pops up.

Find your .tap file and rename it to your corresponding number .tap. Upload it to the correct location.