Hi Mark, actually the Trim command is cutting the surfaces of the object but it is having some difficulty figuring out how to group the different surfaces together into different pickable fragments.

So for example in the model you posted, if you select this plane here:



And then just delete it to get rid of it, you'll see that the slanted block has actually a cut mark on it from some previous run of Trim on that block, it looks like this:



So now you can select some of the faces that you don't want. You can select a face sub-object similar to how you select an edge, by clicking a second time on a solid to "drill in" - but for selecting faces you may need to zoom in a bit so that you can find a good spot that is not nearby an edge to click on because edges get priority. So selecting those faces would look like this:



Then delete those:




There is a bug in Trim but at least it did actually put in dividing edges so that you can remove stuff manually.

I'll investigate to see if I can figure out why Trim is not able to figure out the different groupings of the cut up pieces properly. Thanks for posting the geometry so I can examine it.

- Michael

Hi ...

I did not experience any problem with 'trim' for this block. I did the same thing as Michael did ... created a plane surface through the block and then 'trimmed' and deleted the portion I did not want.

cheers,
eric

Hi Mark, also you could use Boolean difference in this case to slice up the block.

To do that, select the slanted part, run Boolean difference, and select the plane as the cutting object.

That will cut the slanted box into 2 solids, it's slightly different than Trim since there will be pieces of the cutting plane included as part of the result, but you can delete those.

- Michael

Hi eric, yeah the part of Trim that actually intersects the block with the plane is working.

It's the next step where in Trim you can select just a particular portion of the block to throw away that is not working properly.

- Michael

Thanks again, Michael. How you manage to write and debug the software, write the documentation, and still have time to answer all these questions is beyond me. I'm just glad that you can because I love this software.
MoI comes closer than any other drawing package that I've seen, to not impeding or getting in the way of the creative process. It just lets you work and get your thoughts on (digital) paper.
I'm anxiously awaiting the release of V2, while I've still got the money to pay for it!
Mark

Hi Mark, I've investigated this Trim problem that you posted, and I found that there is a bug in Trim when the cutting object produces an intersection curve that is exactly overlapping an existing edge in the model.

I've been able to fix it up for the v2 final release, thanks for reporting it and for posting the model file so that I could see the problem!

- Michael