Extrude or Sweep?

[Oxygen454]

Looks nice, what is UCS anyways?

 

Oh and when I exploded, filleted and extruded the HSS tube, it said:

Select extrusion path or [Taper angle]:

Unable to extrude 16 selected objects.

 

**never mind I did the region command and it worked... up made it one object again

[shift1313]

edit, fillet will work on a closed 2d polyline, but the catch is all corners of the closed object will have the same radius. this works fine for this part but with something like your Ibeam which has a larger fillet in the center of the beam and a smaller one on the edge(if we are talking about steel and not aluminum). In that case i would draw your profile and before using the Pedit i would fillet the edges.

 

 

also to answer your question about region.

 

REGION will convert your lines to a closed polyline. If you drew the rectangle with 4 lines you could use region to join them or pedit. it will achieve the same thing. Region is easier to use and more times than not you will use it, but pedit comes in handy for a lot which is why i told you to use it.

[shift1313]

under the fillet command it will prompt you for [polyline, radius, trim, multiple]

 

if you press P for poly line it will let you select the entire rectangle and fillet all the corners.

 

UCS is user coordinate system. There is a World coordinate system as well. UCS i move around to different places on my work piece. Later versions of cad offer dynamic ucs which moves with the mouse click to selection points on your object.

[Oxygen454]

ah okay that makes sense on the poly and the fillet as well as the UCS. I finally got my tubing with radius's to extract, then I went subtract outside, enter, subtract inside enter and the whole thing disappeared haha

[Oxygen454]

That's messed, I repeated the subtract commands after undoing it the first time and it worked this time...

 

K got a question that was been buggin me... I have a drawing of this gocart, but lets say its any drawing... and its all in 2D normal layout. How hard is it to turn this drawing into 3D? Does it all have to be redrawn?

[shift1313]

DOH, what probably happened was you selected the whole thing and it subtracted itself from itself:)

 

 

just another note that may save you time if doing this to more intricate parts, if you draw the large rectangle first, fillet, then offset, your offset poly will already have rounded edges.

 

Another thing you can do to make 3d solids is REVOLVE.

 

If you draw the cross section of a round part(say a car rim), close it using region or pedit, REVOLVE, it will prompt you for your polyline sketch, and the rotation axis as well as the degrees you want to revolve. Even if you need to add other features to an object this method works great and is a lot faster than trying to build the features up.

 

ill draw up something quick to show you.

[shift1313]

so here is the 2d sketch converted to a closed polyline

edit: not sure why its missing a line but its there in the drawing, if you left that line off it wouldnt work:)

 

 

then using the revolve command

 

 

its really simple and is/can be the basis for a lot of intricate parts.

 

have fun

[Oxygen454]

there we go, square tubing...

 

The lengths and angles, Im not sure how I made them but I think it has something to do with the poly lines for the path...

SquareTube 3D.dwg

[Oxygen454]

Wow dude I just tried that revolve and that was sweet!!

[shift1313]

it had to do with your coordinate system

 

Its important that for square tube the beginning of your path is perpendicular to the sketch.

 

you can tell when you go to the TOP view that your part is at a 45degree angle, and then each part goes off at 22.5degrees.

 

before you start sketching just go to your top view. if you dont have the VIEW toolbar on your screen i would put it there, it makes it easy to switch between views, or you can draw in multi view, seeing 1-4 different views on the same screen.

 

on the top go to your View menu and Viewports, you can go to named viewports and setup your screens.

 

i personally dont like drawing most things that way but if you are working in 3d sometimes its beneficial(to me)

[Oxygen454]

Ya I noticed it turned out kind of weird. I have never used those view ports, that is cool.

 

What I did in that last drawing was, I picked a random point on the screen like I was working on a drawing and wanted to start at that random point. Then I did the coordinates you gave me and I think that is where it ran me into trouble. I think those coordinates too me back to the 0 flipping my object over. I think for tonight, I will work on trying to figure out how to use coordinates to draw a 4 foot by 5 foot square framing out of tubing.

[Oxygen454]

I-beam looks good in 3D. Now that I can draw things from 0,0,0 whats involved to draw in the middle of the screen like that tubing idea i was working on... 4x5

I-Beam2.dwg

[ReMark]

Being able to relocate one's UCS helps to draw in different locations and orientations.

[skipsophrenic]

the other suggestion, is get hold of the CADBible for AutoCAD 2004 and follow the excercises in that - helped me 2yrs ago (and is again 'cos having to re-learn 3d modeling)

[shift1313]

I-beam looks good in 3D. Now that I can draw things from 0,0,0 whats involved to draw in the middle of the screen like that tubing idea i was working on... 4x5

 

 

you can use the orbit, pan, zoom buttons. If you have a mouse with a wheel inbetween your buttons that should zoom in/out rolling it forward/back. The model screen will always start with 0,0,0 in the bottom left corner default but you are free to just move the screen around without redoing your coordinate system.

[Oxygen454]

Its funny that you mentioned the CAD bible, my friend actually just lent it to me so I am going to have a look at it.

 

I find UCS is quite interesting, the different viewports can be a big help if you dont need the whole screen to view a object.

 

 

I have the orbit, pan, zoom buttons working well. What I am wondering is, does all of my drawings have to start off at 0,0,0 and then have to move them to fit up to the rest of the project on the drawing or, can I draw them in I place where I want them to be. For example, if I had a square beam drawn on my page, then wanted to add a channel on top of my beam later on, can i draw it right where the beam is or do I have to draw it back at 0,0,0.

 

What I found was unless I drew at 0,0,0 my object was facing the wrong direction like you said (swift) earlier on.

[shift1313]

no you can draw your object wherever you like. you can start at 6.325,8.003,-20. If you are having issues with your objects extruding the wrong direction its a problem with sign conventions. when you open a new drawing space your Coordinate system will be located at the bottom left with +X point to the right, +Y pointing up, and +Z pointing at you coming out of the screen.

[Oxygen454]

Okay great, so I will just have to figure out how to enter proper coordinates and I will be set.. for a while haha. I do have a print off of the axis symbol that appears on drawings (ucs?). That may help due to the fact that I dont know 100% when to use minus in the coordinates. As far as I remember in trades school, minus is left or down on the x,y axis.

[shift1313]

on your menus up top under view go to Display>UCS Icon and make sure On and Origin are checked. The ON will put a ucs icon in the bottom left hand corner of the screen so you always know what your looking at. The Origin will put it on your screen in the location of 0,0.

 

also in your shademode, when you are in 2d your icon will be a 2d wire, when you switch to 3d it will become a 3d object, x will be red, Y will be green and z will be blue.

 

I would open a blank file, type BOX, and for your coordinates put in 0,0,0 and 3,3,3.

 

type BOX again and for your coordinates type 1,1,3 and 2,2,4.

 

this will create two cubes, one of a 3x3x3 and one sitting on top thats a 1x1x1. use this to play around with your views and rotating. I would switch to hidden shademode so it doesnt get confusing. also if you turned your UCS Origin on like above, the 3d ucs icon will be attached to the bottom corner of your boxes while you rotate.

 

good luck.

[Oxygen454]

Yep everything is set correctly as you said which is good. I will try those boxes and playing with the coordinates and then will write back. Thanks!