# Isometric drawing dimension

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## Isometric drawing dimension

 Let me start by praising to the developer and the community of LibreCAD for the wonderful tool and knowledge they provide for free. I am a mechanical engineer with limited experience in CAD and professional drawing and I would like to understand if there is an easy way to generate in librecad the dimensions for an isometric drawing as the example in the following image: I did some experiment with the aligned dimension, but in order to have the text and the extension lines aligned to the isometric axis I need to explode the dimension and manipulate each single object (that is at least time consuming) Is there any option that I am missing, or any plan to further develop the dimensions commands to simplify the annotations on isometric drawing?
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## Re: Isometric drawing dimension

 Digging into the documentation, I found the following which could help : https://wiki.librecad.org/index.php?title=LibreCAD_users_Manual#Isometric_Grid (old wiki for old GUI but the principles should be the same). https://librecad.readthedocs.io/en/latest/guides/dwg-edit.html?highlight=isometric#isometric-view Fabrice French hobbyist interested in 2D design.
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## Re: Isometric drawing dimension

 Fabrice, thank you for the hint, the wiki references are useful but maybe I am still missing something: this is the result I was able to get in LibreCAD As you can see from the comparison of my drawing with the reference image, the lenght of the upper piece of the plate are wrong (even if the drawing is dimensionally correct), since the lines are drown along an isometric axis The angular dimension is also wrong (150° is the value in the plane of the paper, but the actual value in the isometric view should be 135°) Finally the extension lines are not following the isometric axis, but are just orthogonal to the lines in the plane of the paper As I said, all those things could be fixed exploding the dimensions and working manually, but of course this approach is time consuming and increase the possibility to make a mistake
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## Re: Isometric drawing dimension

 What you want can not be done in LibreCAD. The screenshot of the example you show probably has been made from 3-D CAD program where you can draw the dimensions in the according views / planes and then turn the whole thing into an isometric view. The length of the upper piece of the plate probably is right, just draw a line parallel to the bending edge with a distance of 2.5 units and see where it lies. The angle also is indicated properly, as LibreCAD is a 2-D program and can't know what the angle would be in a straight side view. The isometric grid is just an aid to easily draw 30/60 degree lines, but you can't really draw these with 3-D coordinates.
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## Re: Isometric drawing dimension

 In reply to this post by Rock77 I am wondering how the bending of the metal around an angle changes the dimensions either on the outside of the bracket of on the inside of the bracket. Thus the intended hole at the top may be affected by this effect. See this photo. I agree isometric is confusing and likely not an appropriate view for this part (not needed). p.s. I am new to librecad ... I drew the part 10:1 scale and then when I added the dimensioning notes the numbers are 10 times too large.  Is there an easy way to scale the image without shrinking it 10 times?
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## Re: Isometric drawing dimension

 pt wrote I am wondering how the bending of the metal around an angle changes the dimensions either on the outside of the bracket of on the inside of the bracket. You will bend inner and outer it around a radius, with the minimum radius dependent on the material and it's thickness, so there will be no sharp angle on the inner radius.
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## Re: Isometric drawing dimension

 In reply to this post by pt Scaling: The normal procedure is to draw in 1:1 scale, real life size. Scaling the drawing up or down is then done in the print process, in Print Preview. If you insist on scaling when drawing, you can manipulate the reading in the dimensions in Options - Current Drawing Preferences - Dimensions - Length Factor. But if you check a length with Measure it will show the length as drawn. It is not a recommendable way.