help autocad 2010

[teogian]

Good evening to all: I am new to this purple dress forum and I am working at a company of mechanical processing with cnc centers.
we perform single and small series jobs, talvota I happen to use autocad 2010 to solve problems of pieces not executable on board machine, often relative to profiles in contouring.
I press that little cad 2d I know I learned it myself, and soon I plan to do an evening course.
Since it has not been for so long that we have this software, the other day I and my owner have planted in front of the need to draw a polar series of 30 holes in the diameter of 12mm distributed on a unknown circumference (which had to be found), so that the holes were tangent one with the other (not dry or detached but perfectly tangent to the thousandth of mm) to form a crown.
this because the drilling cycle on cnc flange requires the input of the series diameter and does not offer other options.
I thank those who want to spy on me how to do, using the fastest system
teogian

 

[AntonioV]

an empirical way could be this:

1] command _polygon and design a polygon 30 sides, with suboption _dge, dandogli 12 as side length

2] _circle command with center in a polygon summit, and radius 63] command _array polar (30 copies) of the newly designed circle, compared to the center of the range
n.b.without building anything, you can geometrically determine the center of the polygon with the following expression "transparent":
'cal mee (snapping on two opposite ends of the polygon).

:

 

[teogian]

thanks for the timely cadlandian intervention, the problem that I have is that being accustomed in the previous autocad versions of autodesk in which you could define a polygon with the immision of the size of the side of the polygon itself and the number of sides, now with autocad 2010 this option is no longer, you can do it only by defining the number of sides and the radius of the inscribed or circumscribed circle.
(always there are no hidden commands that do not appear in the command bar I did not notice).
I would have done it in the way you sent me, but now?
And yet it seems impossible that instead of simplifying things have complicated them, there must be an alternative way to trigonometry... .
How can I do that? thanks again teogian

 

[linch]

try to build everything with radius 57,3248
Then let us know.

 

[GP.]

follow the cadlandian procedure correctly, the command has not changed (at least not after 2006):

command: Polygontype number of sides <4>: 30specify polygon center [Spigolo]: sspecify first final point of the edge: select a point and move with the cursor specify second final point of the edge: 12

 

[teogian]

for linch thanks for the interest but with the radius of 57.3248 if the polygon is inscribed has a side of 11.9841, if circumscribed of 12.0502.
But how did you get this value?




for gp.
on autocad 2011 on the command bar appear the following requests to make a polygon:
_type n. sides
_specify polygon center
_type option[iscritto nel cerchio-circoscritto intorno al cerchio]<c>:
Hoop radius

n.b. before I had autocad 14 and it was a fool to make a circumference of holes of the same diameter and tangents among them.
Hello everyone</c>

 

[maxopus]

I can't believe it... I want to evaporate.

 

[maxopus]

the radius of the passing circle for the center of the 30 holes from 12 is 57,401

 

[AntonioV]

teogian,
As you need the f diameter of the flange, you can calculate it like that.

initial data:
l=hole diameter
Number of holes
f = l / sen(pi/n)in your case:

f = 12 / sen(180/30) = 114,80126680206751360467332735304

:

 

[maxopus]

Here's the dwg...

 

[teogian]

I thank Cadlandian and maxopus for the resolution of the problem, although I still have the bitterness of not being able to do it directly from pc with a simple polygon command.
thanks again teogian

 

[numero1]

you can do with a simple polygon command:

for gp.
on autocad 2011 on the command bar appear the following requests to make a polygon:
_type n. sides
_specify polygon center or side (edge in English)_type option[iscritto nel cerchio-circoscritto intorno al cerchio]<c>:
Hoop radius

n.b. before I had autocad 14 and it was a fool to make a circumference of holes of the same diameter and tangents among them.
Hello everyone</c>

in straight where you have to give to the length of the side.
Hi.