Welded coffee table
In this tutorial we will look at how to use the 'WarehouseProfiles' function in the MetalWB workbench to create a simple welded structure. We will also see how to insert a cutting list into the drawing using the FCTreeView macro and Techdraw.
Step 1: Presentation of the exercise
We want to design a coffee table from a sketch using 30x20 tubes. Table structure measures 425 x 400 x 800 mm.
We will use MetalWB and Part Design for the modelling. We will also see how to produce all the files needed to manufacture the welded structure.
The MetalWB workbench was introduced in a previous tutorial. If you have not already done so, you should install it from the 'FreeCAD_MetalWB' repository accessible at this URL. This is a workbench in development so feel free to comment on its use.
Step 2: Creating a cube primitive
- In the toolbar click on the 'MyCube' function - a cube primitive appears on the screen;
- Select the cube in the 3D view or in the tree view to view the object's parameters, in the 'View Properties' window;
⚙ Set the parameters of the object according to the sketch: 400 width, 800 length and 425 height.
Step 3: Application of profiles
- In the toolbar click on the 'WarehouseProfiles' function - a dialogue box appears on the screen;
⚙ In the drop down list labelled 'Family' select 'Rectangular Hollow' ;
⚙ In the drop-down list designated by the label 'Size', check that the selection shows '30x10x1.5'.
NB: The size 30x10x1.5 has already been added to the profile library. This can be done by adding a line to the 'Profiles.txt' file
⚙ The remaining parameters are set automatically from the drop-down lists.
- In the 3D view, select all edges of the cube ;
- In the 'Profile Warehouse' dialog box, press 'OK' ;
- A set of bodies is created from the selected lines. Each body corresponds to a tube cutting.
Step 4: Adjusting the angles
- Locate the profiles that are not tilted in the correct direction. In our case, this means the top and bottom profiles, which must be rotated by 90° in relation to the line axis.
- Select the 8 profiles that need to be tilted,
⚙ In the properties view, change the 'Angle' value to add 90°.
Step 5: Bevels
- Locate the profiles that need to be bevelled. In our case, 45° bevels should be configured.
⚙ In the properties view, change the values 'Bevel End Cut2' and 'Bevel Start Cut2' to get the result as below,
NB: The 8 profiles do not have exactly the same values, some should be cut at a positive angle and some at a negative angle.
Step 6: Length adjustment
- Identify the profiles that need to be reduced in length,
⚙ In the properties view, change the 'Offset A' and 'Offset B' values so that the profiles do not overlap.
Note: As with Step 4, it is possible to configure all the profiles in one operation, by selecting them all before changing the parameter.
NB: There is a second method of adjusting the length: using the Trim/Extend function, which we will see later.
Step 7: Profile offset
- At this point you should have the following result:
- Tilt the vertical tubes to achieve this:
- Find out in the parameters of the properties view how to shift the vertical tubes to bring them closer to the outside of the structure:
Step 8: Modelling the table top
- Well done, you have just finished modelling the welded structure of the coffee table.
- To model the table top, create a new body in the Part Design workbench,
⚙ Move the body so that it is positioned at the top of the table (+ 430mm in Z),
- Model the tray in the usual way: sketch creation, extrusion and then filleting.
Step 9: Cutting list
- Install the 'FCTreeView' macro via the Addon Manager.
- In "Macro ..." select 'FCTreeView.FCMacro' then 'Run'. A configuration window appears on the right hand side of the screen,
⚙ In the drop down menu at the bottom, select 'FeaturePython' so that only profiles are displayed.
- Click on the 'S Sheet' button to generate a spreadsheet,
- Do not change the settings and save
- A Spreadsheet is created with the cutting length for each profile.
- You can modify the spreadsheet to remove redundancy and improve the presentation from the Spreadsheet workbench.
Step 10: Drawing
- With the Techdraw workbench, insert a page,
- Project the faces of the table,
- Insert the spreadsheet with the 'Techdraw_Spreadsheetview' function.
- Be sure to set up the cells that the spreadsheet view will consider.
- You still have to refine your drawing in the classic way: by adding the dimensions, the title block, the annotations, etc.
Thank you for following this tutorial, as mentioned above, feel free to comment on the MetalWB workbench.