DraftSight - Free 2D CAD

[oddcarout]

This is a great post and I was hoping that someone might be able to help me, in DraftSight. I have a shape like the following:

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I would like to draw a curved line from the top point to the bottom point that touches the three horizontal lines. I would like it to follow the horizontal lines. An arc does not work because it uses a radius.

Thank you so much for your help already.

 

[Mainer]

I think you want a spline. Look up spline in the help and see if that will do what you want.

 

[Tin Falcon]

I have a copy of the program but have not used it. But most drawing programs allow you to draw circles and arcs in three ways one option is intersecting three points. so check for that option.
Tin

 

[Tin Falcon]

oddcarout:
first of all please post an introduction in the welcome sub fora. We love helping people but it really helps us help you if we know a little about you.
so please tell us about you, your home shop, and your interest in model engines.

Ok back to the question .
I opened the program and tried a ARC i clicked on points put three points on the screen went to arc clicked on each point and like magic it made an arc connecting all three points . took about 30 seconds. hope this helps.
Tin

 

[kvom]

Use can use a circle if all the points fall on the circle. Click the circle tool icon, type "3P", and then select 3 points with the mouse.

If that doesn't work, choose the spline tool under Draw and click all the points to connect in order.

 

[Mainer]

I thought the OP said an arc was not what he was looking for. Or did he just not know how to draw an arc through 3 arbitrary points?

 

[Jopo]

thanks for your help, i can draw a rectangle but im not grasping how to draw 1 to my precise requirements! i can draw a circle to the exact radius i require but am struggling with the rectangle. can someone give me step by step instructions please

I find the rectangle command very simple and fast to use in Draftsight - exactly the same as autocad. Click the bottom left start point (anywhere you wish - use 'snap' to if you need) enter @xx.xx,xx.xx Y first X second and hey presto. Enter negative (@ -xx.xx,-xx.xx if required
If your rectangle exceeds your screen size go fit to screen.

Jopo

 

[pkastagehand]

I down loaded v3.2 this summer and my cross hairs are gone. Doesn't seem to matter what colors I use for background and for cross hairs. I have a mouse cursor everywhere else on the screen but when I mouse into the graphics area in either model space or on the sheets I loose all cursor indications. Anyone else have this happen?

I've sent a note to tech support email address at Dassault but so far no response.

Paul

 

[RichD]

Hi,
I use a real old DOS version of AutoCad (version 11), but I think other programs have similar features.

To draw a curve intersecting all of the horizontal "endpoints" in your example, use the 'pline' (polyline) command and have your endpoint "osnap" (that's an object snap feature) on. When finished, issue the 'pedit' (edit polyline) command. Select the polyline and choose "fit" to produce a curve that uses the line segments "endpoints" to change the straight line sections into a fitted curve. The 'spline' option produces a similar result but the curve may not be exactly on the points you specified.

By the way. That's a method you can use to manually draw an involute gear tooth curve. In the picture below I think you can see the basic idea behind the tooth curve.

Old timers used to hammer nails into a wooden gear pattern, then attach a string and pencil to "unwind" off the circumference of the nail pattern. The pencil would draw the correct involute curve for that pitch diameter.

Good luck,
Rich

 

[jimmeyer]

when the second entity is selected the first one gets deselected?

 

[ddmckee54]

jimmeyer:

Not sure what you're referring to by the entity getting deselected, I'm guessing that you are fairly new to CAD?

Like RichD suggested, use the "pline" command and select the 5 points that are shown, this will initially give you a poly-line consisting of 4 straight line segments. You're not really selecting or deselecting anything, you're telling Draftsight where the endpoints of each of the line segments that make up the poly-line are located. Be sure that you select the points in the order that you want the line drawn. When you have specified all 5 points, exit out of the "pline" command. Then use the "pedit" command and select the poly-line that you want to edit. You'll either have to use the command line and type in the option you want to select or you might get a drop-down menu, I don't have Draftsight in front of me right now so I'm not sure. If you use the command line, one letter of each of these options will be capitalized - type in this leter and hit the ENTER key to select that option. If you get a drop-down menu, just select the option you want. When you select the "Fit" option of the "pedit" command, you are telling Draftsight to draw the smoothest curve that it can that touchs all the endpoints in the poly-line.

If you want to experiment, try selecting the points in different orders and see if you get the results that you expect.

Don

 

[nel2lar]

Pat
Thank you for your explanation of Draft Sight. I installed it years ago and tried to learn it but for someone that has no idea of CAD operation and getting no where fast. I use your info and give it another try. I would like to have a 3D but if I can not use 2D why pay out all the bucks.
Thank you again
Nelson Collar