# Homework Help: Visualizing an engineering drawing

1. Jan 26, 2016

### theone

1. The problem statement, all variables and given/known data
I am trying to make a model of the attached drawing but am having trouble visualising the middle part of the drawings. I was wondering if someone could describe it to me

2. Relevant equations
-

3. The attempt at a solution
I think it involves two of something like this http://www.jbprince.com/images/K555_zoom.jpg with a hole through them?

#### Attached Files:

• ###### drawing.png
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112
2. Jan 26, 2016

### insightful

That's what it looks like to me, too.

3. Jan 26, 2016

### theone

i also don't understand what this part is:
http://postimg.org/image/ph22yhslp/

4. Jan 26, 2016

### insightful

That's simply the hole. The "bulges" shown are where the hole goes through the beginning of the curved parts of the indentations.

5. Jan 26, 2016

### theone

alight, thanks.
also, do you have any idea what it is a picture of?

6. Jan 27, 2016

### insightful

It's roughly the shape of an "A" arm for an automobile independent suspension, but it could be a mechanical link for many machines.

7. Jan 27, 2016

### theone

im still unsure : are the triangular things solid or just a shape cut into the part?

8. Jan 27, 2016

### SteamKing

Staff Emeritus
The triangular shapes are cut into the part, top and bottom.

You must look at the section view (with the cross-hatching) and compare that to the top view which is on the left.

9. Jan 27, 2016

### insightful

This may, or may not, help (sorry, I'm no sculptor).

10. Jan 27, 2016

### billy_joule

If the drawing is dimensioned correctly you shouldn't have to visualise it at all, just model it as the dimensions state and the correct form will appear.
Of course, being able to interpret the drawing first will make the modelling easier and is obviously an important skill for an engineer.
Your drawing does not have enough information to recreate it exactly, this is a two minute sketch showing the rough form (I've ignored the taper and some fillets):

#### Attached Files:

• ###### A arm.jpg
File size:
29.5 KB
Views:
87
11. Jan 28, 2016

### theone

how did you make that in two minutes; what did you sketch first?

12. Jan 28, 2016

### billy_joule

The whole process:
sketched the top view outline with random dimensions, I then extruded it half the total thickness.
sketched a triangle on the top face and extruded cut ~90% depth of the previous extrusion.
filleted the inner edges of the triangle cut and the tips of the arms (radius of length set equal to the first extrusion)
>this is where I would've added the taper had I done so.
sketched two circles on the side view then extruded cut, this formed semicircular holes with centerlines on the bottom face.
Sketched & extruded cut the large centre hole on the top view
I then mirrored the part abouts its bottom face.

There's many other, probably better ways to do it but it's what came to my mind. I've had no formal CAD training, just practice, learning the hotkeys is important if you want to be fast.

13. Jan 28, 2016