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Blammer
13-05-2008, 03:04 AM
Hi, I'm fairly new to autocad and have a "How To" question.

http://i54.photobucket.com/albums/g81/blammer8mm/Cast%20boolits/JTL.jpg

In this pic I am trying to get the lines centered vertically.

Imagine this is round like a pin.

the "diameter" of .273 needs to be made to .330 keeping the width .077 the same and have this centered in the pin.

Another way to look at it is, these are two rectangles that need to be centered on a common horizontal line.

any suggestions would be helpful. I am very new to autocad so detailed directions would be GREAT!

thanks!

NukeCad
13-05-2008, 08:41 AM
I assume that you are not bothered about the angle of the chamfers?

You need to use the STRETCH command to stretch both the top and bottom lines of the diameter by the same amount.

0.330 - 0.273 = 0.057 / 2 = 0.0285

So

STRETCH enter
select the top line of the diameter, including both endpoints, using a crossing rectangle (bottom right to top left)

type in- 0,0.0285 enter enter (that should stretch the top line)

STRETCH enter
select the bottom line of the diameter, including both endpoints, using a crossing rectangle (bottom right to top left)

type in- 0,-0.0285 enter enter (that should stretch the bottom line)

the dimension for the diameter should now read 0.330

Blammer
14-05-2008, 02:08 AM
thanks, now how do you make sure it is in the "Center" of the pin.

meaning that the .330 dia box is equa distance to the .360 dia band.

NukeCad
14-05-2008, 08:07 AM
Type in the following set of commands

Xline
Enter
H
snap to the centre of the left hand vertical line
Enter
(this gives a horizontal line which is your centre line; usually you would overlay a chain-dot line over this for the length of the component)

Xline
Enter
O
Enter
0.18 (this is 0.36/2)
pick the centre line you have just created
click any point above the centre line
pick the centre line
click any point below the centre line

Xline
Enter
O
Enter
0.165 (this is 0.33/2)
pick the centre line
click any point above the centre line
pick the centre line
click any point below the centre line

Xline
Enter
O
Enter
0.16 (this is 0.32/2)
pick the centre line
click any point above the centre line
pick the centre line
click any point below the centre line

You now have a horizontal centreline with three lines equispaced on either side of it.
These lines are where your diameters should be moved to; then delete the Xlines.

Xline (stands for construction line) is a command that suprisingly a lot of people don't seem to know about; it can be very useful especialy in mechanical draughting. Check it out in the autocad help.

NukeCad
14-05-2008, 12:06 PM
oops
There should be another ENTER after you put in the numbers. But I'm sure you worked that out.

Blammer
14-05-2008, 07:20 PM
thanks! I also put the construction line on another layer.