Isometric Drawing help

[DJ Hands3]

Hello everyone, been practising a mock for a city & guilds exam and I'm having trouble with the attached practice mock.

What I'm struggling with is the fact in Isometric your not suppose to use the offset command but copy and offset the distance instead, this is the part where I'm getting stuck as the isometric ellipses are not easy to do this with, lines are fine if anyone can explain the process to do this would be of great help

all attached in needed to answer the question, thanks

[iskalipsi]

Did you try to draw the isometric in 3D?

[rkent]

Hello everyone, been practising a mock for a city & guilds exam and I'm having trouble with the attached practice mock.

What I'm struggling with is the fact in Isometric your not suppose to use the offset command but copy and offset the distance instead, this is the part where I'm getting stuck as the isometric ellipses are not easy to do this with, lines are fine if anyone can explain the process to do this would be of great help

all attached in needed to answer the question, thanks

I am not certain of your exact needs. Once in iso mode (snap, style, iso) the ellipses are made with the ellipse, isocircle option. You are correct in that you don't use offset with iso drawings, simply copy with ortho on and the iso plane set to the correct one (ctrl+e or F5).

For the object shown you want to draw an iso rectangle the size of the object and then start locating points needed along x and y axis. Copying the lines in each direction to locate the center of arcs, circles, non-iso lines, etc.

[Tankman]

Read up on iso's. http://www.andrew.cmu.edu/course/48-...iles/frame.htm

Chapter 40.

Or, is cheating a bit OK? I sometimes play with stuff I don't need.

Place the image in the drawing and draw over (trace) it?

[Bill Tillman]

Why trace it. I started at 7:34 PM and was finished with the model at least at 8:00 PM. Took a small break in there too. 3D is still some fun stuff with AutoCAD. I drew this all in 2D then made solids. A simple offset got me the insides then I did a little, extruding, slicing and subtracting.

[iskalipsi]

I drew this all in 2D then made solids.

how to do that?

[Bill Tillman]

Some folks will call me a simpleton, but I draw all of my 3D stuff in 2D. I'm not really comfortable with the ISOmetric screens. I should be as my original exposure to isometric drawing was with a 60/30 triangle on a drafting table.

It's not that difficult to create this drawing but you will need the to understand a few things about creating shapes and solids in AutoCAD. In a nutshell I basically took these steps:

1. Layout the center points of the circles which formed the radiused corners.
2. Establish the edge lines of the outside surface using the dimensions shown along with the circles created above.
3. Cleaned up the outline of the outer surface using TRIM and drew a few lines using the TANGENT function.
4. Once I had the outside shape defined I used PEDIT to group all the lines together in a polyline.
5. Then I offset this shape by 3 units towards the inside to get the inner surface.
6. Converted both of these into REGIONS.
7. I then EXTruded the outside surface to the desired thickness.
8. Switch your view to either left or right so you can see the drawing from one of the sides. Either one will work just adjust the next steps accordingly.
9. I drew two lines to establish the points of a plane on which the chamfer towards the front of the part will be.
10. Then I sliced the newly created extrusion along this line to get the final shape of the outer surface.
11. Next, offset this slicing line by 3 units towards the top of the shape to establish the slicing plane for the inner surface.
12. Now move the inner surface outline created earlier up by three units and EXTrude it to the proper depth to match the outer surface.
13. Then SLICE it along the line you offset and erase the splicing lines as you won't need them anymore.
14. Now set your view from the top and SUBTRACT the inner surface from the outer surface.
15. Then draw a circle for the 15R hole at the location shown.
16. Turn this into a REGION and EXTRUDE it to 3 units. Make sure you EXTRUDE this in the right direction otherwise you may have to move it to its final location.
17. Then SUBTRACT the hole from the now hollowed out shape.

There you have it.

I'm sure there are other creative methods. That's the best part about AutoCAD and especially this forum. You can find out how others would create this drawing. And remember, as Merlin said to King Arthur in "Excalibur":

"There's always someone out there cleverer than yourself."

...and he was talking about a fish!

[excuffNof]

hi i m beginnig in realbasic and i would like to know ,how can i draw a cube for exemple but in space2d not in 3d ,i will be use isometric 3d vue but i dont know how can i do this ,do i use vector or bitmap graphics ?thks fr your helpregards Thierry

[DJ Hands3]

Bill thats some good stuff man, I'v had another go here's my latest attempt almost there but some angles are messed up, cant understand how to get the 57 degrees.

Emailed my teacher to see what's wrong but no reply..
Well i suppose its half term.

Can any one recommend any good CAD DVD's to learn from? Our teacher shows the task once with a hand out and then its up to us I work as an electrician so out side the class no pratical hands on - at least I got the student autocad 2010!

[Bill Tillman]

Looks like your getting the hang of it. I'm not sure what you're meaning by the term 57°. I used a much different method, staying in the plan view of the World UCS all the time. I changed the view a few times to get the results needed. But for me, drawings along an isometric axis is not something I do unless there is no other way.

Keep practicing. You'll get there.