Need Help With Drawings

[Bluey]

Hi guys, I've figured out most of the measurements and stuff, the thing I don't understand is how you are able from this drawing and in general (what feature) you used to make the overall curve outer circle joining everything up, from the big circle to the little circle, I managed to do the line from the little one using a 175 degree angle but how do I now join the other end up with the curve by the big circle? Sorry if I don't make sense

 

Also, how am I able to make the circle to the left the correct height, since it is slightly raised from the right one, but can't see any measurements for it?

[JD Mather]

Fillet?

Don't know where you see 175° on that drawing.

The circles are tangent to horizontal line which results in offset center heights.

[Bluey]

I think I read what reMark said totally wrong, also you'll need to talk a bit simpler for me, still very basic using this and confused by what you said sorry and thanks

[ReMark]

Re: JDM's reference to circles being tangent to line.

 

You must have had a basic geometry course by now so you should know what the term "tangent" means. You have two circles, of different radii, tangent to one line. Therefore, it stands to reason that the center points of both circles, relative to each other, are not going to be in line with each other.

 

Check this out...http://www.mathopenref.com/tangentline.html

[Bill Tillman]

From a totally blank drawing to this = 1 hour 5 minutes...included one break for fresh OJ. I'm sure others could have done it faster but I was taking my time. This included all the layout, dimensioning, and notes, sans machining and finishing notes.

 

[Bluey]

Re: JDM's reference to circles being tangent to line.

 

You must have had a basic geometry course by now so you should know what the term "tangent" means. You have two circles, of different radii, tangent to one line. Therefore, it stands to reason that the center points of both circles, relative to each other, are not going to be in line with each other.

 

Check this out...http://www.mathopenref.com/tangentline.html

Yes, but the circles centre is a different height from eachother

[ReMark]

Bluey: You just repeated what I said. Your point is what?

[Bluey]

Bluey: You just repeated what I said. Your point is what?

My apologies, I don't understand how to use it correctly in CAD, I'm going to parametric --- geo cons --- Tangent

It then tells me to select the objects, this is the bit I'm confused on, I don't know how to use the feautre

[ReMark]

I can't advise you. I have no need for using the Parametric feature in AutoCAD.

 

Who suggested you use that method?

[SuperCAD]

Here is a step by step guide to get you started. This creates a tangent line the old fashioned way.

Tangent Lesson.pdf

[Bluey]

Here is a step by step guide to get you started. This creates a tangent line the old fashioned way.

Thanks for that, do I do the same for the outer circles as well then?

[Bluey]

I can't advise you. I have no need for using the Parametric feature in AutoCAD.

 

Who suggested you use that method?

I thought you suggested it along with JD Mather?

[SuperCAD]

Thanks for that, do I do the same for the outer circles as well then?

 

Personally, I would just copy the angled line using the right end as my base point, turn on my tangent snap option and past it on the bigger circle (the bigger circle on the right side, not the biggest circle on the left). Then I would extend the line up to the larger circle on the left. Then I would trim the larger circle between the angled line and the bottom line and apply a fillet at the intersection of the angled line and the arc to form the transitional radius.

[ReMark]

None of my posts contained the suggestion to go parametric.

[JD Mather]

I thought you suggested it along with JD Mather?

 

I don't think I did either - but it would probably be a good move on your part.

Tanget is a parametric constraint - or simply an osnap.

Horizontal is a parametric constraint - or simply ortho (or polar).

All of these things should have been covered in class.

[khoshravan]

Here is a step by step guide to get you started. This creates a tangent line the old fashioned way.

 

I have a simple way:

1- Draw the horizontal line to length (buttom line)

2- Draw two circles at each end of above line with relevant radius. (circle, snap end point, from, eneter radius which will give center of circle and then enter radius)

3- trim two circles with two lines as boundaries.

 

Your tutor has more extra step, especially drawing the smaller circle inside big circle (left one) which I couldn't understand the reason for drawing that circle.

 

Your tutor might be good for geometry class without using AutoCAD. But having CAD's commands in hand, why not use them?

Edited November 28, 2011 by khoshravan
add last sentence.

[Organic]

I have a simple way:

1- Draw the horizontal line to length (buttom line)

2- Draw two circles at each end of above line with relevant radius. (circle, snap end point, from, eneter radius which will give center of circle and then enter radius)

3- trim two circles with two lines as boundaries.

 

Your tutor has more extra step, especially drawing the smaller circle inside big circle (left one) which I couldn't understand the reason for drawing that circle.

 

Your tutor might be good for geometry class without using AutoCAD. But having CAD's commands in hand, why not use them?

 

This is how I would have done it also. Never really had a need to use parametric constraints in AutoCad.

[SuperCAD]

I have a simple way:

1- Draw the horizontal line to length (buttom line)

2- Draw two circles at each end of above line with relevant radius. (circle, snap end point, from, eneter radius which will give center of circle and then enter radius)

3- trim two circles with two lines as boundaries.

 

Your tutor has more extra step, especially drawing the smaller circle inside big circle (left one) which I couldn't understand the reason for drawing that circle.

 

Your tutor might be good for geometry class without using AutoCAD. But having CAD's commands in hand, why not use them?

 

How is this a simple way? You have done nothing to explain how to create the diagonal tangent line.

 

Do a Google search for "tangent two circles" and you'll see exactly why the smaller circle was necessary.

 

Better yet, I'll save you the trouble: http://jwilson.coe.uga.edu/emt669/Student.Folders/Kertscher.Jeff/Essay.3/Tangents.html

[DraftingMadeSimple]

I would use Osnap to draw the tangent line:

1. Start Line command.

2. Type 'tan' and Enter when asked to specify first point. (Or press Ctrl + right click to display snap modes, then select Tangent)

3. Place cursor near first circle and the tangent snap marker will appear. Pick on the first circle where the first tangent point is roughly at.

4. Type 'tan' and Enter again when asked to specify next point.

5. Same thing, pick on the second circle where the second tangent point is roughly at and the tangent line is done.

[khoshravan]

How is this a simple way? You have done nothing to explain how to create the diagonal tangent line.

 

Do a Google search for "tangent two circles" and you'll see exactly why the smaller circle was necessary.

 

Better yet, I'll save you the trouble: http://jwilson.coe.uga.edu/emt669/Student.Folders/Kertscher.Jeff/Essay.3/Tangents.html

 

I think there is a misunderstanding. What you are trying to explain is the theory in geometry and I am aware of that but what I do is better explained by "DraftingMadeSimple" (what a nice name!) posted after my reply.

Using AutoCad has many advantages which makes shortcuts to theory and it is notnecessary to take all steps from theory.

 

BTW thanks for the link.