Extrude along 3D spiral

I have AutoCAD 2000. I have created a 3d spiral (or "spring") using
3dspiral.lsp.

I am trying to extrude a shape along the spiral.

The shape has one side that needs to point to the center of the spiral all
the time. I put the shape perpendicular to the end of the spiral, and
extruded. It did not point to the inside like I need it to.

Drawing at:
http://www.osbornewood.com/spiral.dwg

It has the spring (with a node showing the center) and the shape to extrude
on layer 0, and a test shape with one rough side on layer "layer2" (to make
it easier to see what is going on) in AutoCAD 2000 dwg format. Also, the
item I am will subtract the extruded object from is on a hidden layer,
"layer1".

Pictures of item I am drawing:
http://www.osbornewood.com/item.htm

I would like to get the object to extrude along the 3d spiral with the
inside edge of the shape pointing in.

Please let me know if you know of a better way to draw the item in the
pictures.

Matthew

 

Yes, I have a much better way but it does not involve AutoCAD.

 

Where can I find 3dspiral.lsp?
Thanks

 

Can you give me details?

Matthew

 

Sorry about that.

http://www.osbornewood.com/3dspiral.lsp

Matthew

 

As I said, it doesn't involve AutoCAD. I, personally, would do it in a
program that is much more suited to the task. Now, there are going to be a
lot of people jumping in here saying how this could be done in AutoCAD with
lisp routines or surfacing ect. To those I will say that you can dig tunnels
with a teaspoon too but is it worth it?

 

Hi

"CW" <> skrev i en meddelelse

To those I will say that you can dig tunnels

You are quite right, ------- every time I seen the question I wonder what
shuld be wrong ,making the spiral in 3Ds and then export it in DWG format
and open the new drawing in AutoCAD.,
---------- But even back in AutoCAD don't mean any tea-spoon, acturly you
can invoke Lisp in a compleatly different way now, when you don't need to
calculate geometric information to acturly draw a new entity, as you already
have a spiral drawn 3D and proberly made from 3D faces ; you can make that
entity into a block insert it with different XYZ scale ,guess you could find
even smarter way's to control the diameter of the actural spiral
to, --------- well why even bother extruding along a new path and
calculating the new spiral rod , when a block insert can replace 40 K. heavy
Lisp code ?

P.C.
http://groups.yahoo.com/group/structure-testbench-2/

 

As one who actually likes AutoCad, and does a lot of 3D with it, I tend to
agree with the above statement. There are a few things that seem like they
should be possible, and indeed ARE possible, but they are like teaching your
dog Greek. This example is very similar to one used by Bill Fane to
demonstrate Mechanical Desktop, back in the earlier releases (one of the
Cadalyst columns). He used this example for two reasons - 1) to show how easy
it is in a program like MDT, 2) Because his readers understand how complicated
it is in AutoCad.

Of course that answer becomes purely rhetorical if you don't have MDT or a
similar program, or if you don't want, or can't afford to switch from AutoCad.
In that case, I would try making two 3D spirals, one inside the other,
extruding two different shapes along these spirals, uniting them and then
subtracting the united entity from the base solid.

G Faris

 

Thanks to all for the responses.

The only shape I can reliably extrude along the spiral is a circle, as it
does not matter which way it turns.

This drawing is different from what I have done in the past. I don't think
a circle (or series of circles) will do it.

I would be delighted if somebody could prove me wrong, though

So, my original question is still out there. But, new questions:
What kind of cost would be involved in purchasing software that could do
this easily?

Or, would anybody be interisted in quoting drawing this "spiral" (and the
top and bottom ends, shown in "diagram 1")?
http://www.osbornewood.com/item.htm

Matthew

 

Thanks

 

Sorry Matthew, there is another Lisp program mentioned within 3dspiral.lsp,
that is SOL_SPRING.LSP, could you give me this or tell me where to find it?,
I think we could try to do some modifications to those program to get what
you need, but I do not promise anything, just a trying .

Jose Manuel

 

www.osbornewood.com/SOL_SPRING.LSP

Matthew

 

I got a response via e-mail that said the rulesurf command would help with
this.

A cool drawing was attached. Found at
www.osbornewood.com/column.dwg

It is made up of surfaces. A lisp file should convert this to a solid.

I will let you know when I get more info.

Matthew

 

Hi Matthew,
see
http://home.t-online.de/home/scj.schulz/surf_col.dwg
So you can get the idea to create "twisted columns" as surface-models.
Regards
Jochen

 

Hello Matthew,

If you wish to consider using a third party tool, read on,

Our GeoTools program has a command called GT_EXTRUDER which provides a
simple and easy way to extrude a closed 2d path profile along a path
curve. It internally uses the AutoCAD Extrude command but takes away
from the user a lot of dirty work that is onvolved in otherwise
rotating, aligning and positioning the extruding profile along the
path.

This may be something you are interested to look into. You just have
to create your 2d profile and it will be taken along your 3d spiral to
create a nice solid.

In addition, GeoTools provides over 190 other tools that may be of
interest to you.

Look here for a fully functional download:

Pick up this latest update from
http://www.4d-technologies.com/geotools


Regards
Rakesh

 

Is possible.
You must convert dwg where is the path (spline) in dxf vers 12 and re-import
dxf in to autocad and now you can use this path to extrude process.

read my tutorial - sedia thonet
http://www.cadlandia.com/showarticle.asp?ID=393

--
Alessandro Miele

staff of www.cadlandia.com
first italian cad-portal