# 20 Days of 2D AutoCAD exercises #8

Welcome to today's AutoCAD 2D exercise.

We have the image below to replicate, and luckily we are given all dimensions, which will make the task simpler. Today's difficulty is simply to learn how to draw a circle with specified radius tangent to two objects. As you can see from the figure below, we need to be able to create the R180 circle and R75 circle.

The line AB forms an angle of 30 degrees with the horizontal. To draw this line, follow these steps:

1. Activate the LINE command
2. Click on point A
3. Write @210<30
4. Hit the ENTER key

To obtain the two large circles, you will have to make sure the OBJECT SNAP mode is set in a way to let AutoCAD detect Tangent points, and use the CIRCLE command shown below.

Find this command and use it to draw the two large circles. I hope this exercise was simple and you were able to complete it. If you had trouble, please check the previous exercises. Otherwise, I look forward to having you here for Day 9's exercise.

The whole series
AutoCAD Exercises #1Drawing your first piece of 2D using AutoCAD. Using LINE command and fixing your settings for a better user experience. Learning how to use coordinates and Using exclusively the command window to draw.
AutoCAD Exercises #2Learning how to draw straight lines with definite dimensions. Basic concept for daily use while working with AutoCAD
AutoCAD Exercises #3Learning the use of OSNAP and using skills you gained to design a more complex 2D.
AutoCAD Exercises #4Using some math and drawing lines with specific angles and dimensions. Learning the basic concept of angles in AutoCAD, and actually using the trick main while.
AutoCAD Exercises #5FILLET command and the use of OSNAP. Learning how to place object. Learning how to use center points.
AutoCAD Exercises #6CHAMFER command. Using the CHAMFER command and leaning more about the command window.
AutoCAD Exercises #7how to use HATCH in AutoCAD. You will need skills from Day #4 to have the exercise done, and you will learn how to actually use the HATCH command.
AutoCAD Exercises #8Playing with the TANGENT feature of the OSNAP. You will have a complex figure to replicate, and you will have to learn how the TANGENT feature of the OSNAP works. You will also have to learn a new trick on how to draw a circle using this very technique.
AutoCAD Exercises #9Clear description on how the ARC command works and a complex exercise to try the technique out. All instructions are given for you to easily assimilate the tutorial.
AutoCAD Exercises #10Tricky exercise. You will have to use all technique you have learned in previous exercises to accomplish this one. Hints are given. And an opportunity to ask questions is as well given
AutoCAD Exercises #11Concrete exercise where you will have to see advantages of learning the ARRAY command. A Polar Array is designed and some old techniques you must have learned from the beginning will be helpful.
AutoCAD Exercises #12We have more than an exercise, The aim is to force you to use the ARRAY command. A rectangular Array is to be created.
AutoCAD Exercises #13MIRROR command. The mirror command has not been used since the beginning. This exercise makes it impossible for you if you don't use the MIRROR command. Learning the concept of symmetry in AutoCAD
AutoCAD Exercises #14Create a layers and changing line type. Using the ROTATE command and the OFFSET command. Learning how to combine a set of techniques toward something definite.
AutoCAD Exercises #15Using the combination of all techniques learned so far to come to achieve a complex 2D AutoCAD exercise. Previous learned techniques will be needed in this session and a little bit of math too.
AutoCAD Exercises #16This is a nice AutoCAD exercise that will make you test what you have learned so far. It is testing you ability to combine all you know to get a quite tough exercise done. Of course, hints have been provided to help you get it done.
AutoCAD Exercises #17Revision exercise. Be ready to use your calculator. You will need a bit more of precision in this session. An emphasis has been made on the ROTATE command, OFFSET command and FILLET command in this exercise.
AutoCAD Exercises #18Learning how to draw a polygon in AutoCAD. Here is shown how you can easily construct perfect star in AutoCAD, you may want to convert it into a block for future use. A complex figure is provided as well to help you practice.
AutoCAD Exercises #19Learning how to construct a complex drawing using technique provided to you in previous sessions. This serves as a test, to see how far you have gone since the beginning of this series of exercises.
AutoCAD Exercises #20Exam Day. Grab your Exam eBook for free and come back to me with questions and suggestions on how to make this course easier to understand if possible.
• Chase Caudill

These exercises has been a really helpful way to get me started in the CAD system. Thank you so much for that. I do have a suggestion. You should give instructions on how to trim the circles. I had to look it up on you tube in order to finish it.

• Chase, I am glad the exercises are working for you. Thanks for the suggestion.

If you would like a challenge and also a chance to give back to the community, you are welcome to try the trimming yourself, then send us the results of that with a brief writeup and we will append to this tutorial. We will of course give credit to you. If this interests you, please email info@12cad.com.

• Chase, I am glad you like the exercises. Thanks for the suggestion. We will consider it.

If you want a challenge and give back to the community, you are free to add on to this tutorial and send us the results. We will put it into the article and all credit will go to you.

• Rohan Anushan

@210<30 how to find angle 30

• Paulo Gomes

yes, that is right

• Randy Walker

This helps but it seems it’s greatly lacking information. Maybe add some more steps next time? This is very difficult for beginners, and it even gets difficult to tell which is the measurement line and what the actual drawing is supposed to be.

• Greg Bruell

i can’t find any instruction online how to use the tan tan radius function and i can’t seem to work it on my Cad 2016 for mac