AutoCAD Question - Page 1
Forum section: electronics / projects

author: bostonman
author_rank: Super Contributor
timestamp: April 16, 2020, 02:17:02 am
content: I think this is the area to post such a question regarding AutoCAD.Basically, I'm trying to draw a 2" x 4" (piece of wood) diagonally across a rectangle. The problem I have, I don't know the width (due to unknown angles) of point A and B due to unknown angles.My thought is to draw a 2 x 4, rotate it, and then pull the ends into place. The problem is that I can't keep the width as a 2 x 4 once I move one side.I can't use trig because, as the picture shows, one side of point A doesn't go to the other corner of point B.Does anyone know how I can fit a 2 x 4 in this picture?

author: IanJ
author_rank: Unknown
timestamp: April 16, 2020, 04:09:12 am
content: Group rotate the two sides together but using one side as your marker.Use the trim or extend commands to get the ends in place.Or,Draw one side exactly where you want it then use the offset command to generate the other side at the correct width for the wood and then trim or extend it for length.Don't "pull" the length into place as you will have more chance of skewing things.Ian.

author: admiralk
author_rank: Regular Contributor
timestamp: April 16, 2020, 05:16:41 am
content: Quote from: IanJ on April 16, 2020, 04:09:12 amAlso keep in mind the difference between the actual and nominal width of a 2X4. Some times it does not matter, but other times it can make a real difference.

author: bill_c
author_rank: Regular Contributor
timestamp: April 16, 2020, 01:00:38 pm
content: Draw a circle with 1.5 radius and make a tangent line from that.(edit- first time trying to add image...)

author: bostonman
author_rank: Super Contributor
timestamp: April 16, 2020, 02:08:24 pm
content: QuoteI agree and why the issue. When I built this, I held the 2 x 4 over the spot I wanted, traced underneath, and cut it. Now I'm trying to make a CAD drawing to show (roughly) the length I cut the 2 x 4. I say roughly because there are more cross pieces in the rectangle where the wood is either slightly warped due to drying (it's PT wood) or it's real life and nothing is perfect.I like the circle and radius idea... I'll try that later.Thanks

author: Gregg
author_rank: Super Contributor
timestamp: April 16, 2020, 10:06:48 pm
content: Another way just to give some CAD practice with the commands:• Draw a line longer than needed off to one side of your rectangle.• Use the ‘offset’ command to draw a parallel line 2” or whatever width you wanto As stated previously most 2x4s are 1.5” wide• ‘Select’ the 2 lines and ‘move’ the ‘endpoint’ of what will be the left line to the ‘intersection’ of the top line on the rectangle and the right hand line of the smaller square• ‘Select’ the 2 lines and ‘rotate’ them with the ‘pivot point’ as the intersection in the previous stepo For the rotation amount, use the ‘nearest’ command and select the right hand line and rotate the two lines so that the nearest of the right hand line snaps to the lower right intersection of the large rectangle.• ‘Trim’ and ‘extend’ lines as needed

author: bostonman
author_rank: Super Contributor
timestamp: April 17, 2020, 02:57:51 am
content: I must be doing something wrong.I select the two lines, right click, select rotate, select the top right corner of the two lines, type 'nearest', and it asks:Specify rotation angle or [Copy/Reference] <0>: nearest toAt that point I can still rotate the two lines without being able to select it snaps to the corner I want. If I select the corner I want, it rotates the two lines at about 8 o'clock while my rotation line is at about 4 o'clock.

author: Gregg
author_rank: Super Contributor
timestamp: April 17, 2020, 03:34:59 am
content: OK,Let’s try this again. I use Autocad 14, but others may be very similar. The below is from memory, but if I have to I’ll get out my old XP laptop and try it to see any problems.Assuming the two parallel lines are vertical and longer than needed.‘Move’ commandMove what? Select the two lines; they become dotted or dashedBase Point? Select the top end of the left hand lineMove where? Select the intersection of the small square where it intersects the top line of the larger rectangle. Boom, it should move where you told it.‘Rotate’ commandRotate what? Select the two lines; it should be easy if they hang below the rectangle‘Base Point’ will be the intersection noted above‘Rotation’ will have a bunch of possibilitiesYou should be able to select the right hand line and tell it to rotate to the desired intersectionYou may have to tell the program to use the ‘nearest’ or the ‘perpendicular’ snap on the right hand line and tell it to rotate to the desired intersection.

author: Gregg
author_rank: Super Contributor
timestamp: April 17, 2020, 03:45:23 am
content: There must be 50 ways to draw what you want in AutoCadAn alternative to the above post after you get the two lines vertically placed on the upper intersection:‘Circle’ command: ‘Center’ at the intersection; ‘Radius’ to the lower intersection where you want to place the right hand line‘Rotate’ the two lines; ‘Center’ at the trop intersectionRotate the intersection of the circle and the right hand line to the desired intersection of the lower right hand square, lower rectangle bottom line and the arc of the circle

author: bostonman
author_rank: Super Contributor
timestamp: April 19, 2020, 02:56:14 pm
content: I'm still not getting the results. Attached are two pictures. Picture 1 shows what I want my final results to be (after I went through the steps listed), but, when zoomed in (picture 2), you can see point A is not touching the vertical line.When I select the top left as my base point to rotate, and then 'nearest', it snaps (I think) to an area close, but I want it snapping the right line (although my left line is the base point) to the corner.

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 19, 2020, 03:23:05 pm
content: what happened to circle,radius and snap tangent method mentioned by bill_c?

author: bostonman
author_rank: Super Contributor
timestamp: April 20, 2020, 01:07:52 am
content: QuoteIt snapped, but when I zoomed in, I noticed the right parallel line was slightly beyond the 90 degree intersection indicating the 'nearest' feature placed it at a point slightly beyond the asymptote of the circle (see pictures below).

author: bostonman
author_rank: Super Contributor
timestamp: April 20, 2020, 01:15:56 am
content: Think I got it, I used the 'tangent' feature instead of 'nearest'.

author: Mechatrommer
author_rank: Super Contributor
timestamp: April 20, 2020, 01:32:42 am
content: congratulation. otoh sometime viewres 20000 may improve display, but not sure if it still applies in 2009, we use old R14.