half round spring

Hi All,

I need to draw solid Spring Ring in several sizes and a quick time.

One of it's part is a half round spring. I've been drawing one of it, but it needs one or two days only to make the half round spring.

It's because I draw it in old ways (making path manually), need a lot of patients:huh:. Is there any simple and quick ways to draw half round spring? a tutorial for spring path will help!.

Thanks for help!

HALF ROUND SPRING.pdf

I drew sililar things with Lisp programs. These days I think the fastest way is to use Excel functions to calculate coords and copy/paste the results from Excel to AutoCAD's command line.

I dag for you this old post, maybe you can get some help from...

http://www.cadtutor.net/forum/showthread.php?t=353

I read the thread now (WOW that's a fantastic lisp), and try to learn your lisp. After applying this lisp I'll let you know the result. Thanks fuccaro!

We wait to hear about your progress.

Hi fuccaro!

I load the hehe1.lsp and it works (just like magic), but what I need is only half plain spring (just like your yellow sample not the blue one).

So, I change the parameters and rename it (hehe2.lsp) but it didn't work when I load it.

r1 0.325

r2 2.09

n 15

np 90

a1 (/ pi 0.5 np)

h2 0

n2 0

Well what's wrong with it? by the way what is a1 refers to?

hehe2.LSP

Turn off OSNAP and try this:

(defun c:tet()
 (setq InA (/ PI 1.5))
 (setq turns 10)
 (setq R2 50)
 (setq r1 10)
 (setq po 30);points/turn
 (setq a 0 b 0)
 (setq a1 (/ pi 0.5 po))
 (setq b1 (/ InA turns po))
 (command "3dpoly")
 (repeat (1+ (* turns po))
   (setq p1 (list 0 0 (* r1 (cos a))))
   (setq r (+ r2 (* r1 (sin a))))
   (setq p (polar p1 b r))
   (command p)
   (setq a (+ a a1))
   (setq b (+ b b1))
   )
 (command)
 )

InA is the included angle, in RADians.

Turns speaks for itself

R2 and r1 are as in the image bellow

Points gives the smoothness

Admire Fuccaro work.

As he has suggested, I used Excel Worksheet to calculate the vertices of half round coil (148 nos) and use an autolisp to read and extrude to get this in AutoCAD 2006.

Coil? See for yourself.

CM Hew

Half Spring Coil.dwg

fuccaro wouldn't your telephone cord lisp work to make the spring?

CM Hew: If you already got the points in Excel, you can just paste the data in AutoCAD's command line. No need for Lisp.

SPARKY77: There are a lot of ways to skin this cat!

The tet.lisp works.

I change some variables then rename it (half.lsp) and I get the halfround spring now. Am I doing it right? (please see the attachment)

Mr. FUCCARO = Peri God father with the magic lisp.

sorry forgot the attachments.

half.LSP

half spring.pdf

Only you can tell if the result is good enough for you.

Yes, the first lines in the program are destinated to be changed by the user. I wrote no specially user interface, I just attached that image to explain the meanings of the parameters.