QCad/C2/Drawing-Methods-in-QCAD/English-timed
From Script | Spoken-Tutorial
Revision as of 11:32, 29 December 2014 by PoojaMoolya (Talk | contribs)
Time | Narration |
00.00 | Hello and welcome back to another QCAD tutorial.
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00.04 | Drawing methods in QCAD and knowing coordinate system. |
00.09 | Qcad uses Cartesian co-ordinate system, which consists of two numbered scales, called as x-axis, y-axis.
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00.17 | These are perpendicular to each other. These axis do divide coordinate system into 4 quadrants.
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00.24 | Your work in QCAD will mostly be in quadrant I
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00.27 | The point where these axis meet is called as absolute origin or the origin point. |
00.34 | For this tutorial, I am using the GNU Linux operating system Ubuntu Version 10.04 LTS
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00.40 | and QCAD Community Edition Version 2.0.5.0 |
00.46 | In this tutorial we will see |
00.48 | Cartesian coordinate system |
00.51 | How to use command line to draw objects |
00.53 | and different drawing methods available in QCAD |
00.56 | Let's first see how to use command line to put in co-ordinates to draw points and draw objects of required measurements. |
01.06 | Using the Cartesian coordinate system. |
1.08 | Please have the QCAD application open in your system. |
01.11 | If you want to know how to install QCAD please refer to the earlier tutorial called as 'Introduction to QCAD'. |
01.18 | Which is available on spoken-tutorial website. |
01.22 | Once the application is open from the tool bar on left choose line tool- line with two points. |
01.28 | Now focus on the command prompt, because we are going to use command line to put in exact coordinates. |
01.35 | It is asking to 'specify first point' Let's enter 10 comma 10 |
01.41 | We always add x axis value first and then y axis value. |
01.45 | What it is going to do is, it will add a point 10 units away from x and from y axis. |
01.53 | Hit enter. See the point is entered in relation to this origin or absolute 0, 0
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02:00 | Which is 10 units away from x and 10 units away from y axis.
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02.05 | Now suppose I want to draw a horizontal line in this direction, going away from this pint. Say 10 units.
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02.13 | For the next point, I will add 20,10
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02.18 | X-axis value is 20 because, this point the new point will always be in relation to this absolute zero. |
2.27 | So to meet this distance of 10 I will have to add 10 units to the earlier point's X-value. |
02.35 | And Y value will not change so it will be 10 here.
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02.40 | Now if I want to go vertical line downwards again of 10 units |
02.46 | for the next point at the command prompt I will put then say 20,0 |
02.56 | X-axis value won't change, Y-axis will be 20 units -ve from the earlier value. So it will be 0. |
03.05 | Now again to go horizontal in 9 O'clock direction for the next point I will put (showing on application so pause for 4 sec. 3:11-3:15) 10,0 |
3.20 | Here Y-axis won't change and X-axis will be -10. |
3.26 | In relation to the previously drawn point. |
3.29 | Now to close my drawing I can always put 'c' and hit enter or
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03.35 | I can go back to my original point which was 10,10. |
03.39 | and it will close the drawing. This is how you draw using the command line input.
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03.45 | You can draw any drawing by using this coordinate system by adding, subtracting absolute co-ordinates for any point or vertex between two segments. |
03.56 | Like I did to draw this 10 units. |
04.00 | But this is going to be little complicated. |
04.03 | Rather QCAD offers three easy methods to draw objects with. |
04:09 | First is Relative co-ordinates System, |
04.12 | It uses coordinates that are relative to the last point designated, rather than a 0,0 point of the drawing area. |
04.19 | @ symbol is used to enter data using this system. |
04.26 | Lets try drawing this previously drawn square using relative coordinate method.
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04.30 | Let me clear the drawing area |
04.35 | Go to back line tool- Line with two points. |
04.38 | To specify first point at the command prompt enter 10,10- again x and y axis. |
04.46 | It is going to put point at 10,10 distance. For the next point now that we are using relative system we have to put '@' symbol.
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04.57 | Whenever we want to use relative system @ symbol is a must. |
05.01 | After that, I want to draw horizontal line in 3 O'clock direction of 10 units. |
05.08 | So X value is 10 so I put @10,0 because Y value is zero here. |
05.16 | Now for the vertical line going in downward direction, again for relative I use @ |
05.24 | Then X value is zero but Y becomes -10 because it is going in opposite direction that is why value is -ve here. |
05.36 | For the next horizontal line in 9 O'clock direction, I say @ |
05.43 | Now X axis is -ve, it is going in opposite direction in relation to the previously drawn point. -10,0 |
05.53 | Now to close the drawing I can put 'C' and enter.
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5.57 | Or to go back to that original point. This case I say @ 0- X-axis is zero and Y is going in +ve direction so +10. |
6.11 | This is how you draw using relative coordinate method. |
06:16 | Next is Relative Polar co-ordinate system |
06.20 | It relies on distance and angle relative to the last specified point.
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06.24 | Always it is +ve and represents distance away from the first point. |
06.30 | Let's try and draw the Previously drawn square using this relative polar coordinate system.
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06.36 | In polar coordinate, right towards towards 3 O'clock is always default zero angle. |
06.42 | All other angles are calculated in anti-clockwise direction related to default zero. |
06.48 | So let's go to line tool – again line with two points |
06.52 | at the command prompt specify first point as 10,10 -Enter. Point is drawn. |
07.00 | Now to draw horizontal line of 10 units using relative polar coordinates. I first put @ symbol because it is relative method. |
07.10 | Then I say distance, I know which is 10
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7.14 | I use this symbol (<)less than symbol “<”for angle
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7.23 | I know angle is in 3 O'clock direction, which is zero. (@10<0) |
7.28 | so my horizontal line of 10 units is drawn. |
7.30 | For the vertical line in downward direction I again put @10<270 |
7.37 | and 270 as angle this time because anti-clockwise downward is 270 |
7.50 | for the next point horizontal line in 9 O'clock direction |
07.54 | I say @10<180, angle will be 180, as it is exactly opposite to the default zero position. |
08.05 | Lastly I can always put 'c' to close or else enter the point as @10<90, because it is going in upward direction. |
08.16 | This completes our drawing in Polar coordinate method. |
08:19 | Third is the Direct distance method |
08.22 | Which can be used to draw lines by specifying first point in relation to already drawn object using snapping tools.
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8.30 | By placing a cursor at that point and entering a distance value. |
8.35 | Let's say in this drawing, if I want to put a horizontal line going in 3 O'clock direction exactly from this point. |
8.43 | I can do so by using this direct method. |
8.50 | I choose line- line with two points. Now I know exactly at what point I want line ahead |
8.57 | so from snapping options on the left tool bar I choose 'snap to endpoint' and then go on that point and left click to select the first point. |
9.09 | Now in relation to this I want to draw horizontal line of 20 units. |
9.15 | So I use command line to specify my next point. |
9.20 | I can use relative polar coordinate system here.
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9.24 | Since it is relative I say @ now distance is 20 and in 3O'clock direction, which is default zero angle so I say @20<0 |
9.36 | and Enter. The line is drawn. |
9.39 | Now say I want vertical line of say 7 units going in 90 degrees direction. |
9.46 | I can use now relative coordinate method here. |
9.52 | and say @ (I know 7 is Y direction and X is zero)so 0,7 |
10.01 | and I can use relative coordinate method to draw this vertical line. |
10.07 | Again if I want horizontal line going in 9 O'clock direction say 5 units away.
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10.12 | I can again use relative coordinate method. |
10.12 | At the command prompt I say @ -5 now because X value will be -ve comma 0, Y is zero. |
10.18 | Now I can close down this line, because I know the distance is 7 |
10.33 | I can draw vertical line going towards 6 O'clock directions |
10.39 | Once I know all the different methods I can draw objects with. I can use combination of any to draw objects. |
10.46 | Now to draw that vertical line, I can use relative polar coordinate. |
10.51 | So I say @I know distance is 7, I use '<' symbol, since it is 6 O'clock direction it is going to be 270
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11.00 | This completes our drawing. |
11.06 | This is how you use different methods in QCAD. |
11.10 | Now that you are familiar with drawing methods and the coordinates system in QCAD. |
11.15 | Lets come to the to the ASSIGNMENT. |
11.17 | i would like you to draw diagram as shown in the figure. |
11.20 | You can either use relative coordinate, relative polar, direct method or combination of any method to draw this. |
11.29 | I would like to acknowledge the spoken tutorial project which is part of the talk to a teacher project. |
11.33 | It is supported by the National Mission on Education through ICT, MHRD government of India. |
11.40 | For more information on this please visit following website. |
11:46 | Thank you.
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11.47 | Hope you are enjoying exploring QCAD |
11.50 | This is Leena signing off. |
Contributors and Content Editors
Minal, Nancyvarkey, PoojaMoolya, Pratik kamble, Sandhya.np14