how to offset line in Isometric

[Sengna]

hello, 

sorry if post in the wrong forum, what is the correct way to offset a line in autocad Isometric drawing,  i want to offset red line 3.25 in from mid point just like the distance in green, when i typed 3.25 in it turned out to be 3.75 in.  Is that something to do with wrong plane? i can simply just draw a line command from midpoint 3.25 in but i thought there should be easier way.  sorry  i m new to Iso.

Thanks

Edited March 4, 2019 by Sengna
clarify

[BIGAL]

Check your snaps and grid settings these will jump to a different point.

[Sengna]

hi Bigal, turn off and on snap tool and offset but it still off.  this is the issue below, when i measure the linear distance when offset it will be 3.25 in (green), but for my drawing i need the distance 3.25 in from midpoint to the yellow hidden line not the red line.

 

[steven-g]

offset doesn't work in isometrics, you have to use the copy command, are you using the isometric drafting tools (Isodraft) or just doing it manually, if you use the copy command with the correct isometric plane (F5 - Isoplane Left) and axis locked (F8 - Ortho on)  then it should work.

[Sengna]

so you are saying that use a reference point and copy lines, i am using (DSETTING) command when  changed from 2d  to iso and under SNAP AND GRID tab --I selected ISO Snap.   i also use F5 for changing isoplane. thank you Steven g

[steven-g]

So long as you have the correct Isoplane selected and Ortho on then you should be able to copy just by clicking anywhere in space and moving your mouse in the correct direction and entering the correct distance.

[lrm]

I don't think it really matters which iso plane is active as long as the iso grid is active.  As steven-g states, use copy and not offset when working on a 2D isometric drawing.

In the following figure the green line is 5 long.  If you use the offset command to create a line 5 from it you will get the red line which is parallel and 5 units away.  To get the yellow line use copy followed by 0,-5.

 

If you want to create the magenta line from the cyan line, use copy followed by 5<30.

 

[Sengna]

i don't use grid line that often, i will need to start using it more often