Sunday, 7 June 2015

Surface Modeling Boxer Backrest bar

Bend It – Prologue

This tutorial shows you how to make a Backrest using the cross curve tool.
Top View Curve

Begin by creating a curve in the x-y plane.

Top View Curve - Top View

When viewed in the sketcher, the curve would look something like as shown in figure.
Apply tangent relationship to all connected curves.
Here, the dimensions or even the form of the backrest bar is not important.
This tutorial shows you the approach to create the backrest bar.
You may go out into the parking and take actual measurements.

Side View Curve

Create another curve in a plane parallel to the y-z plane.
See figure.

Side View Curve - Normal View

The side view curve may extend beyond the limits of the top view curve drawn earlier.
But in no case should the new curve fall short of the extents of the earlier curve.
Here too, apply tangent relationship to all connected curves.

Cross Curve

Select the Cross Curve command from the Surfacing toolbar as shown.

First Curve

Select the Side view curve as the first curve.
Click accept   accept   on the ribbon bar.

Second Curve

Select the top view curve as the second curve.
Click accept   accept[4]   on the ribbon bar.

Cross Curve

Click Finish on the ribbon bar.
Soon the cross curve is formed.
The cross curve is neither in the top plane nor in the side plane.
It travels in 3D space, giving us the desired path to create the backrest bar.
In other words, the top view curve is effectively bent by the side curve.

Normal Plane

Hide all sketches.
Create a plane normal to the new cross curve at one of its end.
Use the Plane Normal to Curve command from the Features toolbar.

Plane Created

The new plane appears smaller in size than parallel created planes.
Your figure should now look as shown.

Sketch the profile

Create a sketch (a circle) on the new plane and at the end of the cross curve.
See figure.

Swept Surface

Click the Swept Surface   swepsurf   tool on the Surfacing toolbar.
Complete the extrusion of the circle along the cross curve

Close Ends

In the Swept Surface, click the Close Ends option on the ribbon bar.
This ensures that the ends of the protrusion are capped or closed.

Surface to Solid

Click the Thicken   thicken   tool on the Features toolbar.
The thicken command is on the same fly out as Thin Wall and Thin Region tool.
Select the swept surface and thicken it by a value not more than the radius of the circle..
Finally, round the end faces of the solid handlebar. (see figure)


The figure on right shows the summary and sequence of all commands.

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