Help with Drawing a 3D Solid Chair Foot Rest

[ReMark]

Oh dear no I didn't rotate it, sorry about that.

How could I find out the correct rotation angle to bring it back so its laying flat on its plane again?

 

I drew a vertical line at the open end of one leg from quadrant to quadrant. I changed the precision setting for Angle to 0.0000 then did a List of the line I drew. This told me the angle was something like 72.2827 or something to that affect so I rotated the object that number of degrees using a negative number (-72.2827). Basically that got the foot rest to be standing straight up and down with the two open ends at the top. Make sense?

[ReMark]

Foot rest rotated into position. Note the one white line at the open end (right side) of the foot rest at the top of the image. That line is flat relative to the UCS: X=0.0000, Y=0.0000 and Z=0.0000.

 

[ReMark]

In this image I have drawn the radii for the large arc. BTW...my UCS has X to the right, Y pointing towards the top of my screen and Z pointing out and to the left since I am viewing the foot rest in a SE isometric view (my favorite viewing angle).

 

[ReMark]

Now I have moved to the bottom-most arc and added its radii. Here is a close-up

 

[ReMark]

Next, I've moved to the last remaining arc and do the same thing. Note that this arc shares a common radius with the arc previously work on. To make these radii stand out I changed their color to red. The previous arc's radii remain white.

 

[ReMark]

Now construct your three arcs. Use the method that works best for you. If that means drawing three circles and trimming that's fine too. For the moment let's concentrate on the task rather than the technique. When done use the Pedit command to join the three arcs into a single entity.

 

[ATTACH]23645[/ATTACH]

[ReMark]

What your continuous arc centerline should look like.

 

[ReMark]

Time to bump it up a notch.

 

Here I have added my centerline for the bottom straight run of tube. Immediately after doing that I invoke the UCS command and type "O" for Origin. I want my origin to be the midpoint of the straight line. I use this line and its midpoint to mirror a copy of my right-hand side arc centerline to the left.

 

 

Note: I assumed that at some point you may want to have the full centerline of the foot rest. That is why I mirrored the continuous arc. It is not necessary to do this to actually complete the foot rest however as you'll see in the next step.

[ReMark]

Pictured is one arc, the straight run and two 20 unit diameter circles. The foot rest that we started with has been deleted. We will use these entities to construct our new foot rest.

 

[ReMark]

I've used the SWEEP command to sweep one of the circles along the continuous arc then I mirrored the result to the other side.

 

[ReMark]

Now we use the SWEEP command once more to sweep the remaining circle along the straight run.

 

[ReMark]

Our nearly finished foot rest as shown using the Realistic visual style.

 

[ReMark]

That's the not-so-short version.

 

I say "nearly finished" because the three pieces should be joined using the Union command.

 

I worked with the components of the foot rest just as you gave them to me. Could we have done some things differently? The simple answer is "Yes".

 

We could have joined up all the centerlines using pedit and just used one circle to Sweep along the entire centerline. I'm sure we could have eliminated or changed another step or two. But that wasn't the purpose of this exercise. Anyone who wishes to improve upon it is more than welcome to do so. My methods are not always the best or quickest and sometimes even the Terminator forgets there is a better command at his disposal. I trust this little exercise has proved helpful to you.

 

Now it is your turn. Go for it. I have every confidence in your ability to do it.

[marmo]

Hi ReMark,

 

how's the boy??

[ReMark]

Hey Marco,

 

I'm sure he's doing well. Do you think I went overboard with the instructions?

[marmo]

Your tutorial is perfect!

The boy is very insecure, but I think he will do a good job!

[ReMark]

Rather than insecure I might use the word tentative. But he'll soon get over that I'm sure.

[marmo]

Yes, I agree

[Bobzy20]

Cheers guys I will try that on Monday. Then I'm sure I will have some new objects for you as I need to re-draw the whole chair yet!

[Bobzy20]

I think the main problem was I didn't read the part where ReMark said, 'start by rotating it'.

Another school boy error!