Can anyone help for the school assignment

Draw a circle diameter 1.75

Draw a concentric circle diameter 3.5

Attach the dwg of what you have completed so far (the two concentric circles).

Honestly, I would start again.

Your units are off to start with. Work in metres, not mm. Be accurate with your work. A circle with radius 174.939mm is not the same as a circle with radius 175mm. All your geometry is off like that.

Start by drawing the box at the top and the crankshaft below. Do the connecting rod/gears at the end as they are the hardest.

Here is the basic process of construction, If you were given this as an assignment, you should have enough training to fill in the rest.

Honestly, I would start again.

 

Your units are off to start with. Work in metres, not mm. Be accurate with your work. ....

Start by drawing the box at the top and the crankshaft below. Do the connecting rod/gears at the end as they are the hardest.

The units are inches, not mm, not meters.

Start with the two circles as I CLEARLY STATED in my first response. There is nothing really difficult in the entire drawing, but if you can't do the hard(er) stuff, why even begin? (and there are no gears to be drawn?)

One person who doesn't know what they are doing trying to teach another!

kushab,

I asked you to draw two concentric circles - you went beyond that without first getting that step correct.

Your first circle is wrong - so let's start over and keep it more basic.

Start a new file.

Draw a circle with the diameter 1.75" and attach the file here.

Ignore nestly as well. (I'll explain why later.)

Are you really using Mechanical 2008 version, or are you using later version?

To draw your first circle.

type C on the keyboard and hit Enter.

click anywhere on the screen to place the center point of the circle.

type D on the keyboard and hit Enter.

type 1.75 and hit Enter.

Save the file and attach it here.

We can finish the entire assignment in about 30-minutes, step-by-step.

Thanks for helping me, i am starting from the beggining I draw the two circles .

Drawing1.dwg

I draw the first circle as you said.

Drawing2.dwg

OK, now we are getting somewhere.

In your two circle drawing you used 1.75 Radius rather than Diameter which resulted in two circles twice as big as they should be.

In the second file with just one circle as instructed - you have drawn it correctly.

Go ahead and draw the second circle with Diameter 3.5 concentric (same centerpoint) as the first circle. I think you know how to do that now.

The units are inches, not mm, not meters.

Start with the two circles as I CLEARLY STATED in my first response. There is nothing really difficult in the entire drawing, but if you can't do the hard(er) stuff, why even begin? (and there are no gears to be drawn?)

 

One person who doesn't know what they are doing trying to teach another!

Who says it is inches? There are no units shown on the image as far as I can see. For all we know it could be a large piece of mining process equipment and the units are metres.

Just because in your opinion you start with the two circles does not mean that is the only way to do it. Perhaps gears was not the best term to loosely use although I meant the circles/pins/whatever joining the connecting rod to the piston and crankshaft.

Then draw a line from the centers of the circles vertically.

type L and hit Enter

click one of the circles (AutoCAD should find the center, if not post back and we'll fix that)

move your cursor vertically and click for a length on the line about like this image. (don't worry about the angled line yet)

Now -

click on the vertical line and then click on the grip at the center of the circle.

Click Right Mouse Button and select Copy.

Click Right Mouse Button again and select Rotate.

Type -65 and hit Enter.

Save and attach the file here.

I finished the second circle. thanks a lot.

Drawing3.dwg

Go ahead and draw the vertical line as instructed in post #12 & 13.

OP, the two circles are not concentric. Turn on the 'Center' osnap and recreate the second circle.

Is it good, because AUTOCAD didn't find the center of the circle

Drawing4.dwg

Oops, we need to back up, the circles are not concentric (sharing same center point) and the line is not even close to vertical.

Delete the second circle and delete the line.

whiat to do next ?

Type the command osnaps on the keyboard and hit Enter.

Set exactly as shown in image (Endpoint, Center, Intersection).