Continuing Study of the Modeling “Add-ins” IE 1225 – Introduction to Design and Manufacturing R. Lindeke & J. Voss

Shafting – adding a closed rotation feature  Always consider designing to the Axis of Rotation  These profiles can be open or closed  If Closed, the shape (line) of closure must not intersect the axis of rotation or the shape will fail!  If the profile is open, it must terminate at the axis of rotation or the operation will also fail!

Grooving – subtracting a profile by revolving about an axis  Same issues as in shafts  Consider 3-D elements – and their projection (we’ve used them before and always will!) 3-D Edges 3-D Silhouettes Projections to the drawing plans  Always remember the “tools of the trade” as we sketch and model! But be careful and don’t “overdo” it either!

Draw and Constrain the PROFILE: Be sure to use the profile data entry set for lines – its easy because the lines are essentially straight Vertical or Horizontal

Leads to This:

We build a “Thick” (thin!) half (180) Reversed Shaft

I found that to get the Rectangle Positioned, Constraining the Bottom to the Top of Shaft worked better!

180 and Reverse Direction!

Right Click to Find Axes options!

Note: Circle is on Center Axis!

Final Product:

Creating “Lofted Parts”  Lofts (from the aircraft design background of CATIA’s designers!) are SWEPT surfaces that join 2 or more planer surfaces ALONG a SPINE  Ribs are additive profiles also swept along a CENTER Curve to create Features  Slots are subtractive profiles also swept along a CENTER Curve to remove material from a body

Again Right-Click to Find options (for Planes here)!

Over and Over … Before Projecting the 3-D Elements – Choose both Arc and Line – then indicate 3-D elements Select Both Projected Elements before “SCALING” Change the Projections into Construction Elements after Scaling

Eventually we get to here:

After the 1 st “Multi-sections Solid” (Loft) is performed

Pick the Top Face of the Lofted Halves The SHELL Icon:

Sketch 3-D Elements on Rt End of Boat – use this face to offset a plane …

Desired End Shape: It will MOST LIKELY require you to zoom and click on Close Point 2’s Arrow (as the author suggests)

Double Check – when projecting edges that all Points are Construction Elements! – and don’t be afraid to Zoom … Zoom … Zoom!

Adding Rib – We isolated the 3-D projection of “Sketch 2” to get the center curve

Be Sure to Select Arc & Upper Curve to set Tangency!

Adding Stiffener “From Top” On plane 4 toward stern

To build Seat – I used a Pad and Then a Mirrored Pad for the Stiffener!

Draft – A tool for Making “Patterns and Dies”  Drafted surfaces allow objects to be “withdrawn from a certain direction”  They are needed if we are designing tooling for forging and casting  We often use filleted edges to guarantee that metal from parts or sand will not stick in sharp corners – in forging and casting  Chamfers also help to release too!

Use the Profile tool – build using data entry as much as possible!

Select Rt. Face of Part – Select Draft – Fill as suggested!

Hold Down Control Key when selecting the Faces to Draft & the “Top Faces” as Neutral Elements

Which Becomes this when only the Lowest “Top Face” is Specified as a Neutral Element!

In Casting when we produce Patterns, we need a parting Plane to allow easy withdrawal – We would likely Draft in Opposite Directions: both above and below this plane if we are building a real Matchplate

Notice the Effected of Limited Draft on Front Face – and the Pre-pocketed Rectangle

When Creating Extra Planes – Rt. Click on “Points Selection” box! When added notice it is 40 along the walls but only 10 across the center!

The sizes in the Tutorial were High – I found from Left/6.426 from Top Edges to be a better centering! When considering the Filleted edges!

Make Sure the Rectangle are Coincident with the construction edges! Retain the Upper edge of the top step

Making Edge-Kept Fillets – Do it in 2 steps!

When Limiting the Fillet by a plane – you will likely need to “Reverse the Arrow” direction

After Deleting Inside Draft and Then Pocket – Sketch and Constrain the 2 Circles:

Step 1: Draft the Cyl. Pads; Step 2: Face-to-Face Fillet the two “Cones”

Finally a Variable Radius Fillet on the 2 Edges – From 10 to 30 mm; And a Chamfered edge on the lower step!