Creating GD&T on the Frame

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Creating GD&T on the Frame

 

Go to File arrowDCS Save Management.

Select the Lesson_5_Manual_Gear_Shifter_Asm.CATProduct and select [Save As...].

Navigate to a New folder and rename to "Lesson6" that will be easily accessible later.

Click [Propagate Directory] to save a copy of the CATPart files to the new folder.

In the Save As dialog, rename the Product to "Lesson_6_Manual_Gear_Shifter_Asm" and click [Save].

In the Save Management dialog select [OK] to save the CATIA Product under its new name. The model is not saved until you click OK.

Go to [File] arrowDCS [Save As].

In the Save a Copy dialog, enter "Lesson_6_Manual_Gear_Shifter_Asm." for the File Name, make sure the Type is set to Assembly (*.asm), then click [OK].

In the Assembly Save a Copy dialog, click [Save Copy and Open] to save the assembly under its new name, and open the newly saved assembly.

Close the 3DCS Model Navigator and Creo window for Lesson_5_Manual_Gear_Shifter_Asm.

Click DVTI_dcsUpdateModel Update Model in the new window for Lesson_5_Manual_Gear_Shifter_Asm.

Go to [File] arrowDCS [Save As].

In the Save As dialog, enter "Lesson_6_Manual_Gear_Shifter_Asm" as the new File name and make sure the type is set to Part Files (*.prt).

Click [OK] in the Save As dialog.

Click DVTI_dcsUpdateModel Update Model.

Go to [File] arrowDCS [Save As].

In the Save as dialog, enter " Lesson_6_Manual_Gear_Shifter_Asm" for the File Name, and make sure the Type is set to Assembly (*.asm).

In the Assembly Save as dialog, click [Save Copy and Open] in the bottom left of the dialog to save the assembly under its new name, and open the newly saved assembly.

Click Update Model in the new window for Lesson_6_Manual_Gear_Shifter_Asm.

Click the MC Application Button Icon Application Button then select MC 7500 Save As Icon Save As.

Change the File Name to "Lesson_6_Manual_Gear_Shifter_Asm"and make sure the Type is set to WTX DATA(*.wtx)

Click [Save] in the Save As dialog.

 

Use the following drawing to create the GD&T necessary for the Mounting Block.

 

MVM_Tutorial_frame dwg

 

First, we need to create the datums on the Frame.

From the Model Creation toolbar, click DVTI_gdtlist GD&T, then click the Frame part.

 

MVM_Tutorial_ MC GD&T List

 

The GD&T dialog will open for Frame.

Click [Add] next to Datum Feature, you'll see the dialog shown below.

 

MVM_Tutorial GD&T Frame datum empty 

 

Change the Name to "Datum A".

Click [Add] and select the bottom surface of the Frame as shown in the image below.

 

MVM_Tutorial GD&T Frame datum A Feature 

 

The completed dialog should look like the image below.

 

MVM_Tutorial GD&T Frame datum A Complete 

 

Select [OK] to save and close the Datum A GD&T dialog.

Similarly Create "Datum B" using the 4 holes on the bottom of the Frame.

 

MVM_Tutorial GD&T Frame datum B Features 

 

MVM_Tutorial GD&T Frame datum B Complete 

 

Select [OK] to save and close the Datum B GD&T dialog.

 

Create the size and position on the four Datum B holes in the Frame.

 

Select Size from the GD&T dialog and click [Add]. The dialog will look like the image below.

 

MVM_Tutorial GD&T Frame size empty 

 

Rename to "Size Datum B".

Click [Add] and select the Datum B Hole features.

Uncheck the Symmetric Lower box. For Upper type in 0.2mm and for Lower type in 0mm.

Click [+] to add a new frame for the selected features.

Rename the new frame to "Position Datum B".

In the new frame, change the type to Position Position from the drop down list.

Select Ø diametrical for the zone type.

Set the Range to 0.2mm.

Select MMC Maximum Material Condition as the material condition.

 

We haven't created a datum reference frame (DRF) yet so we will do that now.

 

Select the [Edit DRFs...] button in the lower-right of the Tolerance tab.

 

MVM Edit DRF Button

 

In the Datum Features list of the Edit DRFs dialog, click Datum_A. This will add the label "A" to the first DRF field.

Click [Add]. This will add a DRF with reference A to the Datum Reference Frames list. This can now be used in the tolerance.

We will also add a DRF of A | B(M) to the list for future use. To do this, click the label "B" while in the Secondary box.

Click [(M)] while in the Secondary box to add the material modifier to Datum B.

Click [Add]. This will add a DRF with reference A | B(M) to the Datum Reference Frames list. This can now be used in the tolerance.

 

MVM Edit DRF Dialog

 

Select the [OK] to return to the GD&T dialog.

Select A from the drop-down menu to set it as the DRF for the position tolerance. The completed dialog should look like the image below. Your CadSurf numbers may be different.

 

MVM Postion GD&T Completed

 

 

Click [OK] to close the GD&T dialog.

 

Next we have to create the size and position GD&T on the Mounting Block locating holes.

 

In the GD&T dialog, select Size for the type and click [Add].

Rename to "Size Block Locating Holes".

Click [Add] and select the highlighted features.

 

MVM_Tutorial GD&T block holes features 

 

Click [Close] in the Select dialog.

Uncheck the Symmetric Lower box and set the Upper to be 0.1mm and the Lower as 0mm.

Click [+] to add a new frame for the selected features.

Rename the new frame to "Position Block Locating Holes".

In the new frame, change the type to Position Position from the drop down list.

Select Ø diametrical for the zone type.

Set the Range to 0.5mm.

Select MMC Maximum Material Condition as the material condition.

Set the DRF to A | B(M).

The completed dialog should look like the image below.

 

MVM_Tutorial GD&T Mounting Block size pos complete 

 

Now, we will add the rest of the GD&T from the Frame drawing to the 3DCS model.

 

 

In the GD&T dialog, select Surface Profile for the type then click [Add].

Change the Name to "Profile Frame to Stick Gap Surface".

In the Tolerance tab, click [Add] then select the surface on Frame used for the measure "Stick and Frame Plate Min Gap" .

Click [Close] in the Select dialog.

Set the Range to 1mm.

Set the DRF to A | B(M).

The completed dialog should look like the image below.

 

MVM Frame Profile GD&T Complete

 

Click the [Options] tab in the GD&T dialog.

 

MVM Auto Refine Checkbox

 

You will notice that the Auto Refine check box is checked on by default. Per the ASME standard, Surface Profile varies Location, Orientation and Form. In 3DCS, we use the Auto Refine setting to help vary all of these. With Auto Refine turned off, Surface Profile only varies Location. With it checked on, by default, Surface Profile will vary Orientation at 25% of the overall tolerance, and Form at 0%. These settings can be changed in the Preferences dialog as seen in the image below.

 

MVM Auto Refine Preferences

 

Click [OK] in the GD&T dialog.

 

Next, create the GD&T for the Lever Assy mating hole and surface.

 

In the GD&T dialog, select Surface Profile from the drop down then click [Add].

Change the Name to "Profile Lever Assy Mating Surface".

In the Tolerance tab, click [Add] then select the surface on Frame used to locate the Lever Assy.

Click [Close] in the Select dialog.

Set the Range to 1mm.

Set the DRF to A | B(M).

The completed dialog should look like the image below.

 

MVM Lever Assy Profile GD&T

 

Click [OK] in the GD&T dialog.

In the GD&T dialog, select Size from the drop down then click [Add].

Change the Name to "Size Lever Assy Mating Hole".

In the Tolerance tab, click [Add] then select the hole in Frame used to locate the Lever Assy.

Click [Close] in the Select dialog.

Set the Upper to 0.2mm.

Uncheck the box for Symmetric Lower and set Lower to 0mm.

Click [+] to add a new frame.

Change the name to "Position Lever Assy Mating Hole".

Change the type to Position Position.

Set the zone type to Ø.

Set the Range to 0.5mm.

Select MMC Maximum Material Condition as the material condition.

Select A | B(M) as the DRF.

The completed dialog should look like the image below.

 

MVM Lever Assy Size and Position GD&T

 

Click [OK] in the GD&T dialog.

 

Next, we need to create the Profile and Parallelism on the mating surface between Frame and Mounting Block.

 

In the GD&T dialog, select Surface Profile from the drop down then click [Add].

Change the Name to "Profile Mounting Block Mating Surface".

In the Tolerance tab, click [Add] then select the surface on Frame used to locate the Mounting Block.

Click [Close] in the Select dialog.

Set the Range to 1mm.

Set the DRF to A.

Click [+] to add a new frame.

Change the name to "Parallelism Mounting Block Mating Surface".

Change the type to DVTI_parallelism Parallelism.

Set the zone type to blank.

Set the Range to 0.5mm.

Create and then select A as the DRF.

The completed dialog should look like the image below.

 

MVM Frame Parallelism GD&T

 

Click [OK] in the GD&T dialog.

 

Lastly, we need to create the Profile for the remaining two floating surfaces on the Frame.

 

In the GD&T dialog, select Surface Profile from the drop down then click [Add].

Change the Name to "Profile Stick and L Lever Surfaces".

In the Tolerance tab, click [Add] then select the surfaces on Frame highlighted below.

 

MVM Frame Remaining Surfs

 

Click [Close] in the Select dialog.

Set the Range to 1mm.

Set the DRF to A | B(M).

The completed dialog should look like the image below.

 

MVM Profile Remaining Surfs

 

The fully completed GD&T should look like the image below.

 

MVM Frame Completed GD&T

 

Review the GD&T

If the mesh is off, click DVTI_dcsShowMesh Show Mesh to turn the mesh on.

Click DVTI_dcsDeviate Deviate to show the variation of the tolerances just created.

Click DVTI_dcsNominalBuild Nominal Build.

Again DVTI_dcsDeviate Deviate to see the model deviating for the applied tolerances and moves.

Save the model.