## Turbo Talk => General Discussion => Topic started by: Chris on August 15, 2018, 09:03:14 AM

Title: Introduction to 3D
Post by: Chris on August 15, 2018, 09:03:14 AM
Hi Folks,

I need to design a building. Eventually, I expect that I will produce my drawing the way I build it, meaning with two-bys and sheet goods, but since I've never done this, I'm open to suggestions. For my initial conceptual drawings, though, I think I'll use solid geometric forms. So, for example, to produce a shed, I need a rectangular solid, a prism, and a couple of sheets for the roof. I expect that there are a lot of ways to do this.

One building is a "Tank House", which is a square frustum, with a shed perched on top. The base of the frustum is 18'x18' and the plateau is 16'x16', at an altitude of, say 16'. I think I could easily produce this shape as a wire frame, but that seems primitive to me and probably not the way someone with experience would go about it. Is it possible to produce a rectangular solid and then re-shape one end to make the frustum?

Thanks for the help,

Chris.
Title: Re: Introduction to 3D
Post by: Jeffin90620 on August 15, 2018, 03:56:19 PM
Create two Rectangle objects with the required sizes for the base and the plateau.  Select the base and use the <Tab> key to enter the Inspector Bar (will be the horizontal list of numbers at the lower left of the TurboCAD window).  Adjust the X, Y and Z Position entries to (0,0,0).

Then select the plateau Rectangle.  Repeat the Inspector Bar procedure, except the Z value should be 16 feet (you can enter "16 ft" if you are working in inches).

Under 3D Object (the location for this will vary depending on the User Interface you are using, so it will take some effort to find it), select the Loft command, then click on each of the Rectangles (in order, if you have more than two) and finalize by clicking on the Checkered Flag icon in the Inspector Bar (which, as you may have noticed, changed when you invoked the Loft command).

You will now have either a Loft object or an ACIS Solid, depending on whether you activated Editing History (aka the Part Tree) when you installed TurboCAD.  You can activate Selection Info (<Ctrl><Shift>I) and click on the object to see what you have.

Jeff
Title: Re: Introduction to 3D
Post by: Chris on August 16, 2018, 08:58:38 AM
Hi Jeff,

Thanks very much. I was unable to follow your instructions exactly, but you have been a tremendous help. I did much of what you suggested, but I used the "prism" mechanism. I think this is probably what you were advising and is apparently the same as a "loft", since context menus label the "extruded" parts of my frustum as "loft" for purposes of selection. The two original 2D squares remained, which I deleted thinking them superfluous.

So, now I have my frustum and I also have a cube, which I want to assemble on top of the frustum -- center face to center face. I'm apparently confused by 2D/3D aspects. In 3D, I can't reference the center of a face; I get the centroid of the object. In 2D, I can't move the 3D objects around. How do I assemble two 3D objects center point of one face to center point of the other?

Thanks for the help,

Chris.
Title: Re: Introduction to 3D
Post by: Henry Hubich on August 16, 2018, 11:48:31 AM
Hi Jeff,

Thanks very much. I was unable to follow your instructions exactly, but you have been a tremendous help. I did much of what you suggested, but I used the "prism" mechanism. I think this is probably what you were advising and is apparently the same as a "loft", since context menus label the "extruded" parts of my frustum as "loft" for purposes of selection. The two original 2D squares remained, which I deleted thinking them superfluous.

So, now I have my frustum and I also have a cube, which I want to assemble on top of the frustum -- center face to center face. I'm apparently confused by 2D/3D aspects. In 3D, I can't reference the center of a face; I get the centroid of the object. In 2D, I can't move the 3D objects around. How do I assemble two 3D objects center point of one face to center point of the other?

Thanks for the help,

Chris.

One way: Working in a  isometric view, select the cube, place the cursor in the yellow Reference Point, left-click and release, drag the cube until the cursor lies on one edge of the frustum, press E on the keyboard. The center of the cube now coincides with the center of the frustum. While the cube is still selected, TAB to the Delta Z field of the Inspector Bar and type a number which is half the height of the frustum plus half the height of the cube, then press Enter.

...You should have placed the original rectangles on an invisible layer instead of deleting them. If they were still in existence, you could simply have Extruded the upper one to the required height of the cube.

Henry H
Title: Re: Introduction to 3D
Post by: nikkipollard on August 16, 2018, 09:45:20 PM
I wouldn't delete the "superfluous" lines. Put them on a layer and toggle the layer on and off.

When you need to change things - you wont want to start from scratch. Especially with the deluxe version which has fewer 3d editing tools
Title: Re: Introduction to 3D
Post by: Chris on August 17, 2018, 09:48:45 AM
Hi Folks,

I was seeing things that didn't seem right, so I dropped down to "simple" to see how things should work. The question is TurboCAD's ability vs. my understanding.

I drew a 2D rectangle, and then I tried to extrude it into a brick. No luck. Am I trying to do something that can't be done, or am I simply doing it wrong?  Obviously, I can draw a brick,when I start with a 3D object...

Thanks for the help,

Chris.
Title: Re: Introduction to 3D
Post by: Kevin Taylor on August 17, 2018, 11:13:19 AM
You should take a look at this tutorial:
http://textualcreations.ca/News/?p=1051

I think you may find it very useful.
Title: Re: Introduction to 3D
Post by: Henry Hubich on August 17, 2018, 02:11:23 PM
Hi Folks,

I was seeing things that didn't seem right, so I dropped down to "simple" to see how things should work. The question is TurboCAD's ability vs. my understanding.

I drew a 2D rectangle, and then I tried to extrude it into a brick. No luck. Am I trying to do something that can't be done, or am I simply doing it wrong?  Obviously, I can draw a brick,when I start with a 3D object...

Thanks for the help,

Chris.

First, be sure to create the rectangle as a "Rectangle" and not as four individual lines. Second, work in an Isometric view so you can see what's happening.

Third is a bit more complicated, since we don't know what toolbars are on your personal TCad desktop. If you can find the Simple Extrude tool, click on it and follow the instructions at the bottom left of your screen. If you can't find the Simple Extrude tool, maybe you can get at it via the Draw menu: Draw>3D Object>3D Profile Based>Simple Extrude.

Henry H