center points for holes ?

Good day all
I need some help with Autocad.

I have recieved a drwaing from a client with about 400 holes on a plate. I
need to create a CNC proram with this dwg. To do this I need center points
for each hole. Is there a method with which AutoCad can put a point in the
center of each hole automatically ?

Thanking all in advance


Rui

 

I don't understand why you need to put a point in the centre of each hole.
If the drawing is dimensioned, then the holes will be dimensioned to their
centres anyway.

Doesn't your CNC system use a dxf version of the drawing to obtain the CNC
data?

 

Hi

With AutoCAD you shuld check the system var. Pdmode and Pdsize.
Changing that you have a number of different types of "points" from a
single dot to a circle with a cross or an X or -- or almost whatever
symbol for a "point".

When you changed the two var's it is no problem to make an array of dots,
the Array command will ask you the distance X and Y between the dots and how
many and make exactly what you ask.

P.C.
http://home20.inet.tele.dk/h-3d/

 

Tahnks for the help.

Can't use the array command because the holes are in no fixed pattern. Holes
all over the place.

 

I can import direct to CAM but I still need the center points to create a
drilling pattern.

Thanks anyway

 

Try with Lisp code, good luck...


(defun C:centers ()
(setq circle_set (ssget))
(setq i 0)

(while (< i (sslength circle_set))
(progn

(setq crcl (entget (ssname circle_set i)))
(setq x (nth 1 (assoc 10 crcl))
y (nth 2 (assoc 10 crcl)))
(setq ctpt (list x y))
(command "_point" ctpt)
(setq i (+ i 1))
)
)
)

 

.....of course, if you mean hole=circle

 

This works fine if the holes are in regular pattern. I get the impression
that they aren't.

 

Perhaps not "automatically" but the DIMCENTER command places a small cross
at the center of a circle. Otherwise, you might consider a small LISP
program:

(defun C:CTRPT (/ ss n elist ctr)
(setq ss (ssget "X" '((0 . "CIRCLE")))
n (1- (sslength ss))
);; setq
(while (>= n 0)
(setq elist (entget (ssname ss n))
ctr (cdr (assoc 10 elist))
n (1- n)
);; setq
(entmake
(list
'(0 . "POINT")
(cons 10 ctr)
);; list
);; entmake
);; while
(princ)
);; defun

You may have to adjust PDMODE and PDSIZE to get the appearance you need.
___

 

The software wouldn't be able to read the dimensions. Just knowing where the
edges of the holes are works fine if you are milling/burning them. If you
are drilling them, you need a center point for a target.

 

That does the job very well!
Just set your 'Point' style first (dot, cross, etc.).

 

Hmm. For a laser cutting machine I only need to supply the dxf, with no
dimensions at all. Has to be accurate and full size, of course! Hole
centres are not marked, but the holes are to size also. No good changing a
hole dimension in the design without changing the actual hole size...

 

Same way for a mill. The difference is that with your laser, it is cutting
the profile of the holes. That can be done on a mill too by milling the
holes to size with an end mill but it is far more economical, for average
size round holes, to drill them. In that case, there needs to be a center
mark to locate the drill.

 

Yes, I guess that 'Point' in this case should be set according CAM
software...I dunno much about CAD/CAM software relations so I guess only...

 

You have received a number of interesting replies that involve
LISP functions.

If that doesn't work for you because you need to implement it
differently, try just setting the running OSNAP to "center" then
use the POINT command on each hole (if you prefer to do it
manually). It would, then, be simply
POINT
< mouse click>
<RETURN>
<RETURN>
<RETURN>
(etc., until you8 have established center points for all of the
holes)

 

Paul,

DIMCENTER is one circle at a time.

The lisp routine would get all at once.

Just got to love it.

W. Kirk Crawford
Rochester Hills, Michigan

 

FWIW; I have a list routine called "circnt.lsp" (I think) that outputs
the circle centers to a comma delimited text file. I use R14 and 2K2
and it works in both as best I remember. It outputs the "X," "Y," and
"Z" dimensions (based on the "0,0" point in the drawings. It also
outputs the layer and the circle size (based on the number of places
set in the precision variable). I import into Excel and sort basd on
the layer and remove unwanted holes.
Is this anything like what you want?
R. Wink

 

No.
___

 

Paul, do you always give such long winded explanations?