Hi Brian, I don't think there is any great thread on these specific subjects, so this thread here will be it!

Extend is included primarily so there would be a fairly complete set of standard CAD drafting tools. It's a common part of a CAD toolset to have a function to extend a line to match up with another object - in MoI that's extend.

So for example if you have these 2 lines, if you select the first one and run extend, and pick the second one as a boundary, you will get this:



Of course you can get the same thing by drawing a new line and erasing the old one, but if you have to edit complex blueprints with a whole bunch of lines in them, it can save time to have tools like this that save a few steps and also can work on batches of objects.

But unless you're doing drafting you'll probably not need to use it.


> Curve

Do you mean Construct / Curve here ? Right now this includes project which can project a curve on to a surface, and intersect which will calculate the curves of intersection between all the selected objects. Like for instance if you have 2 spheres that punch through each other, you can use Construct / Curve / Isect to create the circle curve where the 2 spheres intersect one another. Sometimes these curves are useful as one step in constructing a complex object.

Network - this is one of the powerful surface creation tools. You know how loft creates a surface through a series of cross sections? Network is kind of like a loft between 2 sets of cross sections simultaneously. It can give you additional control over the surface that is created. Here is one quick example - here is a network of curves:



It's kind of hard to tell from that angle, so here is another angle from the top that shows more of the "network" nature of that arrangement:



So there you can see that these curve are arranged in a kind of 2 directional grid. I've highlighted the curves in one direction there. For network surface, the curves should be arranged in this kind of a 2-directional grid style (although it is ok if they are arranged radially and come together at a point too). Like I mentioned, it's kind of like loft in 2 directions at once, the highlighted curves there are like one loft, and the other set of curves is the other direction loft. But in Network these are combined together into a single surface. So for example in this case that creates this object:



Anyway, that's a very simple example. You basically might use Network when you want more control over the created surface than just a loft gives.


Offset - offset works on either curves or surfaces, you might use it on curves to create a curve setup that has equidistant properties, like here for example is one curve and its offset forming an outline for a thick wall. There are different ways to create thickness, like you can use shell if you want to, but sometimes it is useful to do the more low-level offset approach to make individual parts:




Blend - blend is about creating a smooth pieces in the empty space between the ends of 2 existing parts. You can use it on curves or surfaces. Here's a curve example:



Starting with those 2 curves that have a space between them, selecting them near those ends and running blend created a new 3rd curve that connects between them smoothly.

Here's blend on surfaces - 2 surfaces with some space in between them, select the 2 edges and blend calculates a new 3rd surface that is smooth between them:



Hope this helps, let me know if you need any more info on any of these.

- Michael