Specifying the length of a line

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Specifying the length of a line

Bluescreen
Sorry for the newbie question but I am a newbie.

How do I specify the length of a line drawn in Librecad? I'm aware I can set a point and drag the line with my mouse, but how do I accurately set the length of a line, in my case, in mm.

Cheers.
Glenn.
"It's a basic truth of the human condition that everybody lies. The only variable is about what." - House M.D
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Re: Specifying the length of a line

dxli
Hi Glenn,

You may use snap toolbar or command line to specify precise coordinates.

for example, to draw a line 1.25mm in length at angle 25 degree:

0, main menu: Edit->Current Drawing Preferences->Units, set main drawing units to mm ;
1, main menu: Draw->Lines->2 points , to start line drawing;
2, choose the start point; Please notice the relative zero is moved to the start point
3, when prompted to choose the next point, use spacebar or mouse clicking to activate the command line;
4, type in @1.25<25 in the command line, press enter to accept and draw the line; @ means coordinates is relative (the the current relative zero). You can use cartesan coordinate such as "@1.25*cos(25*pi/180), 1.25*sin(25*pi/180)"
5, right click to stop the line drawing action.

dxli

Bluescreen wrote
Sorry for the newbie question but I am a newbie.

How do I specify the length of a line drawn in Librecad? I'm aware I can set a point and drag the line with my mouse, but how do I accurately set the length of a line, in my case, in mm.

Cheers.
Glenn.
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Re: Specifying the length of a line

Bluescreen
In reply to this post by Bluescreen
Thanks Dxli that was great.

How do I draw a line a specific distance from another line, such as would be the case when drawing a thread on a bolt. Is there a way to specify the distance from the original line and draw a line from that.

I'm thinking that I would need some sort of reference point to measure distances from, so in the case of a bolt I can get the thread depth correct. Would it be advisable to use construction lines to help (going back to my drafting days at school) get the proportions right. And if so, how would you remove them afterwards? Sorry for the wordiness of my reply, I'm not good at thinking onto a screen.

Glenn.
"It's a basic truth of the human condition that everybody lies. The only variable is about what." - House M.D
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Re: Specifying the length of a line

dxli
Hi Glenn,

if you want to specify the distance manually, you may choose "draw parallel" for lines, and and "draw concentric" for arc/circles.

If you want to use construction lines instead, I suggest you to add a layer "construction", change to construction layer to draw those construction lines, and change back to your layer to for other drawings. When you are done, you can hide/show the construction layer by one click.

dxli

Bluescreen wrote
Thanks Dxli that was great.

How do I draw a line a specific distance from another line, such as would be the case when drawing a thread on a bolt. Is there a way to specify the distance from the original line and draw a line from that.

I'm thinking that I would need some sort of reference point to measure distances from, so in the case of a bolt I can get the thread depth correct. Would it be advisable to use construction lines to help (going back to my drafting days at school) get the proportions right. And if so, how would you remove them afterwards? Sorry for the wordiness of my reply, I'm not good at thinking onto a screen.

Glenn.
Jay
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Re: Specifying the length of a line

Jay
In reply to this post by Bluescreen
I have a related question, how do you specify the direction of a line in DMS mode?  I can draw by using the format @15<45 but not @15<45˚15'15”, what I've been doing is importing from AutoCAD (which uses the format @15<45d15'15”) succesfully but when trying to draw I always get a "Expression Syntax Error”.  I've set the units in DMS, the drawing displays info in that format but won't allow me to use it.  Thanks for the help!
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Re: Specifying the length of a line

LordOfBikes
Administrator
Hi,

after a first look into the sources, this format isn't supported by the LC command line.
But you can enter a double precision decimal number. Thus 45°15'15" is equal to 45.2541667.

If there isn't already a feature request, I will create one.

Armin
Jay
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Re: Specifying the length of a line

Jay
Thanks for the tip and I appreciate the help with the fix!