Rotate 3D

Charles Alan Butler

See DWG. I would like to rotate the 12x12 square tube around its long axis /length to align the sides with two of the angled lines that it's center intersects.
Initially, I create a short length of 12x12 tube and placed a line in the center of the tube along its length, then made it a block.
I use the Align command to place the tube in its horizontal position but then needed to rotate it.
I gave up on the block and exploded them in hopes I could do better with the solids.
In side view it was easy to rotate the tubes that align with that view but the other two plane are giving me fits.

Any help with my education would be appreciated.

Charles Alan Butler

I was able to figure it out.
By setting the UCS to the face of the 12x12 tube end and use the PLAN command to align my view.
Turn off the zOsnaps , draw a vertical line using NEAr snaps for a reference line.
Turn ZOsnaps back on.
Then use the rotate3d command using the Z reference line I had as the rotation center.
Picked 2 points vertical on the face.
Then pick the points (my routine ) for the new rotation angle

Opposite corner:

3R
Entities in set: 2
Select axis by [Entity/Last/View/Xaxis/Yaxis/Zaxis/2points] <2points>:
Specify the second rotation axis point:
Rotation angle or [Base angle/Copy]:b
Base angle <0>:
Second point:
New angle: 'pang
Pick first point for angle.
Pick second point for angle.82.7318731903173
New angle: 82.73187319031727

If you have a better way, please share.

Thanks

Richard Webb

Is this what you were trying to do? (see attached) When I first looked at the drawing, it was not entirely clear which tube was "the" tube.

I think that I used more or less the same approach. Started by setting a UCS to the face of the tube and then a few quick rotations of that UCS until I was happy with it. Helps to have the UCS icon visible and I also set the Lookfrom to respect the UCS vice WCS. After that, added a construction line along the target axis and then rotated from the existing intersection. Bada boom, bada bing!

Charles Alan Butler

Richard,
Did you use the 3 point pick to set the UCS?
Do you keep the Lookfrom set to UCS or switch back & forth?
My UCS Icon is set Lower Left but I don't see it.

Thanks for the info.

Richard Webb

No, I used the Face option, selecting the end face of the target tube and then some flips to get it oriented where I wanted it. I set Lookfrom to UCS and left it there throughout, although I'd probably switch it back to WCS (or a different UCS) to continue working on the drawing. When I open the sample drawing, the UCS icon's state is Off and I had to turn it back on via _ucsicon.

Charles Alan Butler

Thanks for that info.

Charles Alan Butler

Practicing with the FACE option of UCS I now see how useful it is.

Is there a way to set UCS to the imaginary plane shown in the attached?
If you pick as shown the Y is set in a direction straight up & not rotated to the plane of the line which is picked.
So the Z axis is perpendicular to the plane of those 2 lines. See picture 2

Roy Klein Gebbinck

I think you are misinterpreting the UCS result you get when you pick the 3 points as indicated in 'BC UCS.JPG'. Keep in mind that the plane defined by the two lines tapers. To verify the UCS is aligned properly you can _Id the end points of the two lines. They should be co-planar with the XY-plane of the UCS and therefore their Z coordinates should be zero.

Charles Alan Butler

The problem is that the face of the tube is not rotated yet to align with the lnes.
They are close, as I did it by eye, but not exact.

I figured it out:
UCS pick Origin, then X point in the picture below, then Y in the vertical.
UCS again, and now enter Y and rotate -90 deg
This results in the desired UCS with the bottom end points of the reference lines being Z and
the lines in the Y plane.
Now can rotate the Tube face to be parallel / perpendicular to the Y plane.

Charles Alan Butler

@Roy Klein Gebbinck said:
I think you are misinterpreting the UCS result you get when you pick the 3 points as indicated in 'BC UCS.JPG'. Keep in mind that the plane defined by the two lines tapers. To verify the UCS is aligned properly you can _Id the end points of the two lines. They should be co-planar with the XY-plane of the UCS and therefore their Z coordinates should be zero.

Yes the two lines have Zero Z in the first picture.
I was able to align the two tubes in that plane.
But I still can not align the diagonal tube in that plane because the center axis is, well, diagonal.
See new picture and file attached

Charles Alan Butler

OK I guess I was picking the wrong line for Y in the last tube alignment because I just got it to work.
Is there a "Make Parallel / Perpendicular" command in BricsCAD?
Where you can grab an edge and another object & the routine would make Parallel in the current UCS.

Charles Alan Butler

Got all three tubes & flanges aligned to the blue lines.
It is a bit tricky picking in 3D & also managing the Zosnaps.

I'm finding Pipe (Round Tube) easier to work with because it has a center snap at the ends.
The square tube with rounded corners is tricky. I seemed to do better if I build them with a center line & make them blocks.
Still have to figure out how to extrude or extend face while in the block.

Roy Klein Gebbinck

@Charles Alan Butler said:
The problem is that the face of the tube is not rotated yet to align with the lnes.
They are close, as I did it by eye, but not exact.

Aha... Now your OP finally makes sense to me. The fact that the dwg you posted seemed to already contain the result you were after confused me.

The easiest method I can think of is to use the 'normal' 2D _Rotate command:

1. Align the UCS with an end face of the profile.
2. Switch off the DUCS.
3. Use the _Rotate command (see command history and image). The fact that the points you pick have different Z coordinates in the current UCS is irrelevant for the command.

Command History:
: RO Select entities to rotate: Entities in set: 1 Select entities to rotate: Rotation point: end Snap to endpoint of: <-- P1 Rotation angle or [Base angle/Copy] <58.4730>:b Base angle <180.0000>: end Snap to endpoint of: <-- P1 Second point: mid Snap to midpoint of: <-- P2 New angle <58.4730>: end Snap to endpoint of: <-- P3

Finally two things:

1. I find it helpful if the UCS icon is diplayed at the origin: _UcsIcon > _ORigin.
2. There is a relatively new entity snap called _gcenter.

Charles Alan Butler

Thanks Roy, I see now that the Z is of no concern in the 2D roatate.
Your method is easier.
The -gcenter is new to me as I was stuck in ACAD 2006 until I purchased BC 16 when it first arrived.

Patrik Sparrman

A nice little rule of thumb for 3d-rotation is that the rotation axis starts at pt1 and goes to pt2, then take your right hand and aim your thumb along the axis and the rotation goes the way you fold your hand. Always works nicely when you get lost in space.

Charles Alan Butler

Thanks Patrik, I'm sure that will come in handy.

Hans De Backer

The new Manipulator control, introduced in V18, makes this kind of operations a lot easier, to give you some idea I attached a short movie.
In the movie, I first rotate the flange block back to a known rotation angle.
Then I select the pipe solid and bring up the Manipulator control: this can be done either by using the Manipulate command, or by keeping the left mouse button slightly longer (250 ms) down than usual when selecting the pipe.
The Geometric Center snap is used to move and align the Manipulator with the center of the top face.
Next, the pipe is rotated back to a known angle by snapping to one of the main axes.
Next, the flange block is clicked to extend the selection to hold not only the pipe but also the flanges.
Finally, the Manipulator is used to rotate the selection to the desired inclination by snapping to the endpoint of the reference line.
As you will notice, reading the textual explanation takes far longer than doing it for real...

Charles Alan Butler

Wow, way cool.
I have 18 so I'll practice that.
Thanks

Charles Alan Butler

Darn, did not realize that the upgrade broke the QUAD again.
Off to Tech support to get that fixed again.
There really should be a SIMPLE way to upgrade BC without trashing all the toolbar & palette settings & locations.

later

Charles Alan Butler

I have found that if the end of the square tube is not perpendicular to the axis the MANIPULATE method does not work.

Hans De Backer

To discuss 3D manipulations of a model, and provide an unambiguous description of the initial model and the desired modifications to it, using words is not the shortest way to go, by far... one would need many thousands of words to provide the information that is expressed and contained in a 'before' and 'after' model.

So, to avoid time waste and misunderstandings for everyone interested in this topic: could you attach a model that illustrates a case when 'the manipulate method' does not work?

By the way: I wonder what you mean by 'the manipulate method'? The 'method' I described here is universally applicable and used in many disciplines, it involves no magic of any kind: tweak the input into a known form for which an easy solution exists, then apply that solution.

Charles Alan Butler

Hans,
Please forgive my clumsy explanation, I meant using the Manipulator control.
It could very well be that I was misusing that. I was able to rotate the tubes using your method when the face was unmodified but when I revised the structure I extruded the face to contour into the 30" pipe. I agree, at least a thousand words.
DWG at link, picture below. https://www.dropbox.com/s/kj31yikurldu8tz/S02-111917.dwg?dl=0
The angled brace was copied from the other side after I extruded it. I was trying to place the copied tube into place & it became an impossible job for my limited skills.

Let me say I have a new appreciation for 3d cad.
Thank you so much for the help you have already given me,
I'm going to get this but it's taking more effort than I expected.

What totally throws me off is the main legs taper together and there are 3 legs. So for me only the front face of the tower is even close to a plane I could work with.
Then the angle brace is, well angled off the horizontal plane. Looks like I jumped into a project way over my head.

Charles Alan Butler

This is the tube end that I was trying to align with the Manipulator control.
It worked well with a square cut end.

Roy Klein Gebbinck

If the end face is not perpendicular to the axis, you can still use the 2D rotate method if you first align the UCS to a side face of the tube and then rotate the UCS +90/-90 degrees around the X or Y axis.

Charles Alan Butler

Thanks Roy, that is how I got it done. I am finally getting used to moving the UCS & rotating axis so the object is easier to manipulate.

The 3D environment is coming into focus a bit more.

Ian Johnson

Charles, looking at your model I see you have profiled the square sections around the tubes. I understand this can be achieved by subtracting one solid from another (and losing the cutting solid). Is this the method you use or is there a better way and not see one solid disappear?
Thx

Charles Alan Butler

Put the square tube into the correct position with ends short of contact with the pipe.

Make sure the tube face is perpendicular to the tube axis. I made a mistake & tried to use a tube after I sliced it & the face was not perpendicular.

The result was a bent tube. You don't want that.

Set dmextrudemode to 2

_dmExtrude
Select entities/subentities to extrude or set [MOde]:_MO
Choose type of created entity [SOlid/SUrface] :_SO
Select entities/subentities to extrude or set [MOde]: select the FACE of the end of the tube
Entities in set: 1
Select entities/subentities to extrude or set [MOde]: ENTER
Specify height of extrusion or set [Auto/Create/Subtract/Unite/Taper angle/set Direction/set Limit] :
Enter L
Select the pipe to extrude to.

The tube is lengthened to mate with the face of the tube.