www.5xj.com rhino_tutorial

The major steps in extruding the ring:
1. draw a ring id blank
2. postion the stone (move and rotate)
3. draw ring cross section and extrude it
4. draw shank contour, extrude and mirror it
5. boolean subtract the id and side objects from the ring

create a new layer named 'ring'
edit, layers, edit layers..., create new layer, 'ring'

set the layer color
(left-click on the square) and

set the material color
(left-click the round graphic)

the material properties box
for rendering the ring

set the color and
reflective finish

to make drawing the finger id
object easier, turn off the stone object

edit, layers, one layer on...
select the ring layer and click on ok

This ring will be a size 6

Calculate the ring id
from this foumula:

ring id = 11.6 + 0.8 * size
ring id = 16.6mm

to view circles turn
on the wireframe display:
wireframe, maximize right viewport

draw a circle for the ring id
curve, circle, (center, radius),
enter 0,0 for the origin,
enter 'D' for the diameter,
and enter 16.6

extrude the id circle:

view, viewpoet layout, 4 views

solid, extrude solid, straight,
click on the circle, enter,
12 (this is the extrude distance, both sides)

zoom extents:
ctrl + alt + e

rendered display
ctrl + alt + r
all 4 viewports

Now we need to position the stone
Turn on the Ghosted Display
ctrl + alt + g
all 4 views

the stone cullet has to be
slightly above the ring id
(or you will create a hole in the finger)

To make selecting the stone
easier, turn off the ring layer
edit,layers, one layer on

move the stone up
transform, move, select stone - enter,
click start pt, click end pt

turn on all layers
to view the ring
edit, sayers, all layers- on

if necessary move the stone again
so it is approx 0.5mm above the
ring id surface

rotate the stone to align
the stone with the finger

display 4 views
view , viewport layout, 4 views

transform, rotate, click on stone - enter,
select the first ref pt

select the second ref pt

this shows the stone in the final position

maximize the right view:
view, maximize
view, set view, right

drawing the ring section
is a bit of trial and error

draw some arcs
keep the shank thickness to
somewhere around 1-1/2 to 1-3/4mm

curve, arc, (start, end, point),
left click the mouse to select the points

draw some straight lines
from the arc end to near the stone top

allow height and thickness for the stone bezel

curve, line, single line,
left click the mouse to select the points

delete the extra lines and arcs

mirror the arc and line:
Transform, Mirror,
click on the line and arc, enter

select start of mirror plane point
select end of mirror plane point

the mirrored line and arc

note: sometimes it is easier
and more accurate to enter
points from the keyboard
rather than with the mouse
when selecting the mirror plane

ie. type 0,0, enter
and then type 0,10
(or any non zero Y axis number)
enter

draw an arc connecting the arcs
turn on the object snap display
right click on OSNAP
check the 'end' box

curve, arc, (start, end, point),
left click the mouse on the first arc
left click the mouse on the second arc
click the mouse on a point to give approx a 1-1/2mm thick shank

draw a line to connect the top two lines:
curve, line, single line,
left click the mouse on the first line end pt
left click the mouse on the second line end pt

extrude the ring section:
solid, extrude solid, straight,
select the arcs and lines of the ring section
enter,
view, viewport layout, 4 views
if BothSides=No then type B and enter
move the mouse (in the front or top view)
and left click the mouse to select the extrusion distance

the extruded ring

from the front view
draw a lines for the shank profile,
and extrude

mirror the shank profile object

subtract the shank profile objects from the ring:
Solid, Difference,
select the ring object, enter
select the shank objects, enter

subtract the ring id object from the ring object

note: the shank profile polygon (lines)
used to create the shank profile
object are still present

If you wanted a concave shank
just replace one of the lines with an arc
and then extrude, subtract as above