Part Modeling in Pro/Engineer WildfireDeveloped by John Bellinger

Last Updated: February, 2006 for Pro/E Wildfire 3.0 by David Urban

Introduction

In this tutorial we will be creating a three-dimensional model of a wrench. Three dimensional modeling is a vital part of the CAE process; without a model there would be nothing to analyze or machine. The wrench you will be making is double ended, with jaws of 1 and 1.25 inches. It will be made from aluminum. When you are finished your model will look like below.

Setup

Step 1: Start ProE Wildfire from Start - All Programs - PTC - Pro/Engineer - proewildfire

Step 2: From the left side of the screen, right-click on your W: drive (near the bottom of the tree). Select New Folder and name it Wrench. Now select this folder as your working directory (making sure it’s highlighted like “temp” is in the figure below)

Now that ProE is loaded and using the correct directory, we will create a new part that will become the wrench.

Step 3: Select the Create New Object icon . This will bring up the New window.

Step 4: In the Name dialog box type in your name (ignore the “group xx” in the figure below).

Step 5: Unselect Use Default Template. At this point the New window should look like this

Step 6: When the New window is correct, click OK. This will bring up the New File Options window.

Step 7: Select inlbs_part_solid. Pro/Engineer lets you work in either the metric or imperial system. Also you can make sheet metal or solid parts. We will be making a solid part in the imperial system.

Step 8: Type “24-101 Wrench Project” into the DESCRIPTION box

Step 9: Type your name into the MODELED BY box. When you are finished the window should look like this.

When your window matches the window above, click OK. The screen will change to the Modeling view, which looks like this. The modeling view is used to view and edit three dimensional parts. Later we will see the Sketcher view, which lets us create two-dimensional sketches which we will then turn into solid parts.

Sketching the wrench body In this tutorial, we are creating the wrench as an extrusion. Extrusions are parts with two dimensional geometry and a uniform thickness. To create the body of the wrench, we must sketch the outline in the two-dimensional sketcher view and then give it a thickness to extrude it into three dimensions. We start by modeling the body of the wrench.

Step 1: Click the Extrude Tool icon, which is in the toolbar on the right side of the screen.

The bottom of the screen will change to the following

Step 2: Press the Placement button (in Red). A tab will pop up as shown:

Click the Define… button

A Sketch window will appear and the prompt at the bottom of the main screen will ask you to Select a plane or surface to define sketch plane. We will be sketching on the plane labeled TOP. Mouse over the label of the TOP plane and it will highlight, as in the picture below.

Step 3: Click on the TOP datum plane and click Sketch in the section window. This will bring up the References window. Click Close.

NOTE: If the reference window does NOT come up, don’t be alarmed. ProEngineer assumed your references as the other two planes, since there are no other objects to act as references.

The screen is now the Sketcher view. Sketcher is used to create or modify two dimensional geometry.

A quick explanation of the sketcher toolbar is in order next. Not all the tools are used in this tutorial.

Step 4: The wrench we will be making is symmetric about the horizontal axis. We can therefore save ourselves some time by modeling only the top half and mirroring the features to make the bottom half automatically. Because we know that we will be mirroring the wrench, we should start by making a centerline. Select the right arrow next to Create Lines and select the Create 2 point centerlines button

shown here . Click on the left side of the horizontal axis, and then the right side of the horizontal axis. This will create a red centerline coincident with the horizontal axis as shown below.

Step 5: Now we will create the end of the wrench. Click the right arrow next to the Arc tool to select the Arc fly-out and pick Create an Arc by selecting its center and endpoints as shown.

. Click once on the horizontal axis to the left of the vertical axis to set the center point, then on the horizontal axis further left to set one end point. Move the mouse cursor up and over the center, then back to the horizontal axis and click a third time to finish the arc. The size is not important right now. The finished arc should look something like below.

Step 6: We will be dimensioning the arc to be the proper size.

Select the blue arrow at the top right of the screen. When your mouse is over the dimension number you wish to change, it will turn blue as shown:

Now Double Click the number and you will be able to enter a new value for this dimension:

Step 7: Change the value of the dimension to 3.00 inches by typing in 3. This will change the distance between the center of the arc and the vertical axis to 3.00 inches.

Step 8: Change the radius dimension (shown in blue) to 1.00 inches.

Your screen should look like this:

AN ALTERNATIVE WAY OF DEFINING THE RADIUS:

As you will see in the later screenshots, the 1” dimension we just defined can be defined like the 3” dimension shown above (as a distance, not a radius).

Select the “Create Defining Dimension” tool from the right side toolbar.

Click the left end of the arc, then the centerpoint of the arc, then CLICK WITH THE MOUSE WHEEL between the two. This defines the distance between the center and endpoint of the arc (essentially the radius).

Now deselect the tool and double click the dimension value to change it to 1”.

RESUME

Step 9: You can zoom in and out of your sketch by rolling the mouse wheel back or forth respectively. Zoom out slightly so you can see an area of the screen as shown below.

Note: The position of your mouse will affect the lateral motion of the zooming while you scroll. Try it

Note Also: If the rectangle in the background, or the labels FRONT, PRT CSYS DEF are distracting, you can turn these labels off in the toolbar on the top of the screen. The one on the left turns Datum Planes ON/OFF, and the one on the right, turns the Coordinate System ON/OFF. The other two are irrelevant for now.

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Step 10: Create an identical half-circle on the right side using the same technique. The resulting display should look as follows:

Step 11: We will be creating the handle between the ends of the wrench. Select the Create 2 point lines

button from the line fly-out as shown . Click on the middle of the right side of the left arc and draw a horizontal line over to the right arc. Click on the right arc and then center click to stop drawing lines. The end result should look like this.

Step 12: Create a dimension from the handle to the horizontal centerline by selecting the “Create

Defining Dimension tool” , clicking on the line you had just created (left click), clicking on the horizontal axis (again, left click), and then clicking the middle button (scroll wheel) between the two. Change the dimension to .60 inches. The result is shown below.

Step 13: Next we will trim off the arc where the wrench end meets the handle. Select the Trim button

and click on the arc segment between the handle and the horizontal axis. It will disappear. Repeat on the other side. The trimmed sketch will look like the following.

Sketching the wrench jaws Now we will create the jaws. The left jaw will have a one inch opening and the other will be 1 and 1/4th inches. We will do this by removing material from the sketch you have just created,

Step 1: Begin by creating a horizontal line from the leftmost arc to almost the center of the arc. Zoom in so the display shows only the left end of the wrench. After creating the first line the view should look like the image below.

Step 2: Dimension the new line so that it is .577 inches long and .5 inches from the horizontal axis. Properly dimensioned it looks like the following.

Step 3: Next we will create an arc that will form the base of the jaw. Select Create an arc by three

points or tangent to an entity at its endpoint from the arc fly-out . Click once on the horizontal centerline to the right of the center point of the jaw, then once on the right end of the line you created in Step 1. At this point an arc will follow your cursor. Move the cursor to the right , and the arc will follow the cursor. When the center point of the arc you are creating (the yellow crosshairs) is on the horizontal centerline, there will be a red dot in the middle of the crosshairs. Also make sure that the center of the arc is not coincident with the center point of the jaw, and there is no letter T appearing at the left end of the arc.

INCORRECT PLACEMENT OF THE ARC:

The red lower case T means that the arc is Tangent to the line. It is not supposed to be.

When all these criteria are met, left click again to finish the arc. When properly completed, the arc will look like below.

Step 4: Create a horizontal dimension between the ends of the arc. Select Dimension , then click the two endpoints. Center click in the space high above and between the two endpoints to create a horizontal measurement. Modify this dimension to be .288 inches. It will look like the following when you are completed.

Step 5: Trim the excess arc from the end of the jaws. The completed jaw will look like the following.

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Step 6: Repeat steps 1 through 5, using the other end of the wrench. Dimension the right end so that it matches the following image.

Finishing the sketch At this point we have a sketch of half the wrench. Fortunately, you do not need to model the other half of the wrench. Because the wrench is symmetrical about the horizontal axis, we can mirror all the geometry from top to bottom. Mirror is a great time-saver. After we mirror, we will extrude the sketch into three dimensions.

Step 9: When you are certain your sketch matches the sketch above, click the Select Items button , Drag a rectangle (shown in white) around ALL of the sketch components. When you let go, all the entities will be highlighted in RED

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Step 10: With all the geometry selected, we can mirror the wrench to obtain the complete geometry.

Select the Mirror button and click on the horizontal centerline. The result will be as follows. At this point, take a screenshot of your view to include with your lab write-up. Here is a procedure for taking a screenshot.

i. Make sure that the main pro/Engineer window is in the foreground by clicking on the window.

ii. Hold down the Alt key and press the Print Screen key on the keyboard, then release both. This copies the foreground image to the windows clipboard.

iii. Start Microsoft Paint from the Start menu: Start- All programs -Accessories - Paint.

iv. Paste the image into paint by holding down the Control key and pressing V, then releasing both.

v. Save the image to c:\temp and close Paint

Step 11: The mirror completes the sketch, so click the Continue with Current Selection button . The view will change to look like the following.

Step 12: Change the extrude depth to .25 inches by typing .25 in the dialog box shown below, then click the GREEN check mark in the lower right.

Filleting the 3d wrenchFillets are gradual curves that connect geometry replacing sharp corners. They are used because sharp corners cause stress concentrations, which are areas of higher stress than the area away from the corner is experiencing.

Step 32: Select Hidden Line view style from the top toolbar and then rotate the part to the angle shown below by holding down the mouse wheel and dragging the part.

Step 1: Create fillets on the corners connecting the handle to the jaws. Select the Round Tool button

from the right toolbar .

Enter 0.5 for the Fillet Radius in the bottom left:

Click on the four corners shown to create the four fillets. The first one is highlighted in Blue in this picture:

Once you’ve clicked all the corners, your screen should look like this:

Click the GREEN check in the bottom right of the screen.

Wrap-upFinally, you must capture a copy of your completed wrench to include with your write-up. Make sure to save your wrench.

Step 1: Switch to Shading display mode and verify that your final wrench looks like the following picture.

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Step 2: Rotate your wrench to an interesting angle and take a screenshot to include with your write-up.

Your Lab Write-up

Each team should prepare and hand in one write-up. Your write-up should include the following:

1. A cover sheet that has the title "CAE Lab1 Write-up", names of the team members, and date of the lab.

2. Include the two-dimensional, dimensioned line drawing of the wrench.

3. Include the three-dimensional, shaded drawing of the wrench.

4. Consider the case in which the wrench is used to tighten a nut and bolt to a torque of 50 ft-lbs. Use the actual dimensions of your wrench for the length of the handle and the size of the jaw. Using methods of statics, calculate (i) the force that must be applied to the handle, and (ii) the magnitude of the two forces produced at opposite corners of the hexagonal bolt head. Include all calculations, and follow the same guidelines as you do in completing your homework.

The write-up should be handed in at the beginning of the recitation two weeks from the lab date.