Raised surfaces

Raised Text and Logos from a SURFACE
I recently had to create a raised shape (logo) and some text on a curved surface. What I learned about manipulating surfaces was mainly achieved through
asking questions and lots of trial and error. I decided to write it all down for reference at a later date because I know quite well that several weeks ( or even hours) from now, I won't have a clue how to repeat it. What I went through covered several complex techniques and so I thought that my experiences might be of interest to others. I got most of this knowledge from several people on this site, with special thanks to David Janes. I have used some of his quotes directly in this text.
-----------------------------------------------------------------------------------------------
The Project
To keep this simple I will say that the original surface was half of a sphere (5" dia) created on the FRONT plane using the revolve tool with a rotation of 180 degrees. Make the convex surface face the screen. Create a datum plane that is offset from the FRONT plane by about 3" (so that it clears the sphere) and is positioned towards the screen. Name this PROJECTION_PLANE.
The raised shape is a rectangle that is 1.0" high and 2" long. It is created as a sketch on the PROJECTION_PLANE. It is placed a little above center and somewhat to the left.
There will be text placed below the rectangle.
-----------------------------------------------------------------------------------------------
To create the raised (or sunken) shape:
Select the surfaces to raise the shape from; they'll turn salmon colored (click on the sphere). Click 'Edit>Offset' Get the Icon for 'Expand', not 'Standard Offset Feature' (in Dashboard). Set the expand distance and direction. Open the Options menu and click the Sketched Region radio button for the 'Expand Area' Define your sketch (rectangle) Make your "SIDE SURFACE NORMAL TO SURFACE" (last radio button). Depending on the complexity of your raised shape and the surface that it is raised from (and the amount that it is raised), it may fail when you click the spectacles at the bottom right. You may have to choose "SIDE SURFACE NORMAL TO SKETCH" instead.
You don't even need to project the curves onto the surface and you should get raised shapes based on your sketch.
----------------------------------------------------------------------------------------------
To STEP the raised surface:
I also needed to STEP the curved rectangle surface to end up with different heights. To do this make the original offset(expand) as high as the total height (with step). Then offset another surface from the sphere to the distance that the bottom of the step will be. You can now extrude a cut of the required step shape, from the PROJECTION_PLANE down to the new surface. The sketch for the cut can overlap the edges of the rectangle. The extrusion will have to be created as a surface (not a solid) to be able to CUT the raised rectangle surface. This will leave a hole that can be covered by using points, curves and another surface (STYLE or BOUNDARY BLEND).
-----------------------------------------------------------------------------------------------
In my case, I had to SPLIT the front, curved, raised rectangle surfaces into more than one surface to have a finished surface with more than one color. If you want to do this, first decide on "NORMAL TO SURFACE" or "NORMAL TO SKETCH" and do not change it later or your sketched lines used to break the surface will probably fail.
I only wanted to SPLIT the raised, curved rectangle surface but I found out that it doesn't work unless the shape that was to be the new, split surface is completely contained inside the raised rectangle surface. The projection must not touch the edge of the raised surface. To have the new surface touch or extend past the raised surface, I had to included the raised sides and at least part of the original surface that it was raised from.
To SPLIT a curved rectangle surface into two (or more):
SKETCH a curve on the PROJECTION_DATUM plane using the rectangle in the background as a guide. Draw the required shape in the correct position, making sure the ends of the sketch are connected. It becomes a little awkward as the rectangle is shown as a raised object and its edges are visible. You can extend the lines off the rectangle and either join both ends together or run each line past the edge of the original surface (sphere). Joining both ends is usually neater and can help eliminate other problems with split surfaces that extend too far. Just keep the lines that extend off the edges of the rectangle close to the edge (but not too close).
Highlight the sketch and use EDIT>PROJECT. Click on the surface collector and then using CONTROL KEY, select all the surfaces that the sketch will project on to. As well as the curved surface of the rectangle, include the sides of the rectangle that should show the projection and the sphere surface. As you choose the surfaces, the projected portion of the sketch will appear on the surface. The projection should show as an unbroken loop on the chosen surfaces. If any section is not visible, then probably the sketch need to be tweaked to clear the edges of the rectangle.
Before the TRIM is allowed the surface must be chosen first. Click the sphere surface. It should highlight red around all its borders, including the rectangle (not the sides). Click EDIT>TRIM. Make sure that your quilt is listed in REFERENCES under TRIMMED QUILT. Click the TRIMMING OBJECT SELECTOR and pick the projected curve. When you click on the projected curve, the complete loop must highlight. If one leg fails, go back and find out why (probably the sketch). When you get the HATCHED surface and yellow direction arrow, click the direction selector until both sides of the curve have direction arrows AND ARE HATCHED. This means that it's splitting the surface and keeping both sides. If you get the arrows but no hatching, there is something wrong with the projection (usually the SKETCH).
-------------------------------------------------------------------------------------------------
Raised TEXT:
You can't create text when you go to define your sketch inside of EXPAND (icon is greyed out). So you have to first create the text with the SKETCH tool before you enter OFFSET (EXPAND). The font must be a vector font. FONT3D worked good and so do TTF types. Save the sketch.
Then when offsetting (expanding) the surface, select OPTIONS and define the sketch. Choose the PROJECTION_PLANE. Use SKETCH>DATA FROM FILE and choose the text sketch and position scale and rotate it. Then click SKETCH>EDGE>USE (to use the edge of the existing text). Choose one letter at a time and LOOP. Accept and repeat with remaining text. When you click the check mark, the text should be raised. Set the distance and direction etc.
If the original surface is made from curves, then crossing a curve with a shape or a text letter, could cause problems. Keep the text or shapes to either side of the surface curve.
If you split the surfaces as explained above, you can't expand text (or anything else) across two (or more) separate surfaces. Some of the text will be missing. This is a good reason for keeping the lines for the sketch (for surface splitting) close to the rectangles.
------------------------------------------------------------------------------------------------
Text or logos produced this way will create a shape that protrudes from the surface in one direction and is hollow on the other side. Choose which side you want (raised or sunken) by FLIPPING. If you don't want the other side of the original surface to show the sunken or raised shape, first OFFSET the original surface by enough to cover the shape inside. This creates a second surface inside of the original. You can choose to cap the open edges between the offset and the original. I preferred to leave the inside exposed while I was working as I could see the other side while developing the shape. This was another reason for making the original curved surface just a half sphere.
The actual logo and text that I used are more complicated than the sphere and rectangle in this example and I found that after splitting the raised surface, I had a hard time ROUNDING the edges. Some worked and some didn't and some looked positively ragged and were unusable.
---------------------------------------------------------------------------------------------
I hope that someone gets some use out of this. Thanks again to all who helped. Peter
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nice summary and the closest we've had to an actual tutorial posted orginally here. BTW, some of the issues with surface quality, inability to round or merge could have to do with accuracy issues. Try absolute accuracy, especially if this will be used down stream in molding, for merges, inheritance features, core/cavity cutouts. One proof that it can enhance geometry quality is the fact that I've eliminated many geom checks by bumping up the accuracy value.
David Janes
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.