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Cadastrophic
8th Dec 2003, 06:50 am
I want to extrude a shape along a line that contorts and twists through all planes. Until now, I've been extruding it in pieces, and then trying to join them up, because when I try to join the polylines, I'm informed the lines are not all in the same......
Is there a way of drawing complicated 3D polylines that can be extruded? What have I missed?
hendie
8th Dec 2003, 09:55 am
why don't you join the polylines before extruding along the path ?
Flores
8th Dec 2003, 03:34 pm
You can extrude along a "3dpoly" also.

Flores
Mr T
8th Dec 2003, 08:16 pm
Think about either

typing in coordinates

or

drawing a box/crate containing enough points to snap onto

Nick
flrrb
9th Dec 2003, 05:22 pm
I wrote a small LISP that creates a TUBING command. It will take a cylinder and keep asking you to extrude one of the ends along a path.

I use this to make pneumatic tubing runs that bend all over the place through 3 dimensions. You can modify it to suit your needs. Instead of creating a cylinder, you could just have it select any entity to extrude, I suppose.

Here it is:

(defun c:tube(/ ssz pt1 pt2 szr linepath)
&#40;setq ssz &#40;getdist "\nSize of Tubing &#40;Dia.&#41; <3/8>&#58; "&#41;&#41;
&#40;if
&#40;or
&#40;= ssz null&#41;
&#40;= ssz 0&#41;
&#40;< ssz 0&#41;
&#41;;End OR
&#40;setq ssz 0.375&#41;
&#41;;End IF
&#40;setq pt1 &#40;getpoint "\nStart Tubing at&#58; "&#41;&#41;
&#40;setq pt2 &#40;getpoint "\nEnd of First Straight&#58; "&#41;&#41;
;Now make the first Cylinder
&#40;setvar "cmdecho" 0&#41;;echo off
&#40;setq szr &#40;/ ssz 2 &#41;&#41; ;&#40;szr = ssz/2&#41; get the radius from the diameter
&#40;command "_cylinder" pt1 szr "C" pt2&#41;

;now extrude it until there is no face selection
&#40;while &#40;setq linepath &#40;entsel "\nSelect next path segment or &#91;Enter&#93; if done&#58; "&#41;&#41;
&#40;command "_solidedit"&#41;
&#40;command "_face"&#41;
&#40;princ "\nSelect face to extrude&#58; "&#41;
&#40;command "_extrude" pause ""&#41; ;select one face
&#40;command "p" linepath &#41; ;path, 0 taper
&#40;command "_exit" ""&#41; ;ends the solids editing
&#41; ;end while
&#40;princ&#41;;adds that clear line
&#41;
Cadastrophic
9th Dec 2003, 09:14 pm
Thanks flrrb, that sounds exactly like what I want! Does it cope wit fillets od radii?
Another problem; I haven't a clue about lisp routines. Can you please explain, in novice terms, what I do with your code.
Thanks very much.
flrrb
9th Dec 2003, 10:05 pm
As long as the paths that you select are valid (lines arcs and plines, etc.) it will extrude along them.

(setq ssz (getdist "\nSize of Tubing (Dia.) <3/8>: ")) will ask the size of the tubing to create (ie the cylinder)

(setq pt1 (getpoint "\nStart Tubing at: "))
(setq pt2 (getpoint "\nEnd of First Straight: ")) Makes the two endpoints of the cylinder

(setq szr (/ ssz 2 )) ;(szr = ssz/2) get the radius from the diameter
(command "_cylinder" pt1 szr "C" pt2) makes the cylinder pt1, pt2 and the radius szr

(while (setq linepath (entsel "\nSelect next path segment or [Enter] if done: ")) asks for the path and the WHILE keeps asking until there is nothing selected.

(command "_solidedit")
(command "_face") begins the soledit command

(princ "\nSelect face to extrude: ")
(command "_extrude" pause "") ;select one face to extrude

(command "p" linepath ) ;path, 0 taper extrueds along the path previously selected


You must have the lines and arcs already set up. The easiest way is to make connecting lines, then fillet them as needed. THEN run the tubing command.

Here is a finished pic of my 3D tubes:
http://www.bbcc.ca/hosted/gallery/albums/userpics/normal_CP-0038%20Piping%20Detail.jpg
http://www.bbcc.ca/hosted/gallery/albums/userpics/normal_Direct%20Gas%201.JPG
Cadastrophic
9th Dec 2003, 11:13 pm
Thanks for your time, but I still haven't the foggiest clue what you're talking about. Ah well.
I really like your work....hmmmmm shaddows, that's something else I want to learn.
Mr T
9th Dec 2003, 11:35 pm
Thanks for your time, but I still haven't the foggiest clue what you're talking about. Ah well.
I really like your work....hmmmmm shaddows, that's something else I want to learn.

Shadows. Within the RENDER command and then LIGHT command. Low ambient light then tweak point and spotlights.

Nick