chopping the corners off a block

[rols]

I have a flattened cube, basically a thick rectangular block. I want to chop the top two corners off to make two right-angled 'shoulders'.

I've cut the faces so that the entire block is divided into small cubes, what I want to do is remove the top left and top right of those cubes. I've tried everything I can think of but have failed miserably.

If I take the 4 faces and 'extrude' inwards it looks like the cube has disappeared, but all that seems to have happened is the faces now overlap what's left and it's a mess. If I push the front face inwards then the rest of the side of the block tilts in, which I understand. I've tried dissolving things, collapsing things. Clearly I'm missing a piece of understanding.

If I start with the block short, divide up the top face and extrude the middle piece upwards I get the 'head and shoulders' I want, but I can't work out how to start with the full block and remove two cubes at the corners to end up with the same thing.

[micheus]

I've cut the faces so that the entire block is divided into small cubes, what I want to do is remove the top left and top right of those cubes.

If you want to produce to holes that is the command you should look for [Hole]. In this case, you will see the back faces through the hole - not internal faces. If you need that, then you may need to use Intrude which you can define a thickness for the mesh.

Wings3D works with closed meshes, so you will not be able to remove the faces with any other way.

If I take the 4 faces and 'extrude' inwards it looks like the cube has disappeared

yes, that will not work.

If I start with the block short, divide up the top face and extrude the middle piece upwards I get the 'head and shoulders' I want

Do a test with Inset [LMB]. Moving the mouse you will "scale" the new face and keeping pressed the [LMB] and dragging the mouse you will bump the face.

[rols]

I tried hole as well, indeed it gives me internal faces, ie a hollow into the box which wasn't what I wanted. Intrude does the same, gets rid of the block but leaves the remainder empty and not closed.

Either I'll continue starting small and extruding out the piece I want, which works perfectly but requires me to think backwards (start small, add on instead of start full and remove). Or else I found I can loop cut the whole object into separate objects, each of which is a long thin block. I can then shorten the ones I want to make gaps in the edge, and then join them all back up together again. That's pretty long-winded but works, I suspect it also means there's a basic concept I haven't grasped.

[micheus]

You could add an image to show us what you are looking for. Maybe, we could suggest something else.

[rols]

Have to do this in two as my compressed jpgs are still too large.

1) is a simple block, chopped up ready to have the top middle section extruded

2) I've extruded it to get a head-and-shoulders. This is the result I'm after. However it's part of a longer process so I wanted to come at this from the other way around.

hence 3) is a new starting point. It's a taller block which I've divided up, I want to get rid of the corners, one highlighted, to get back to that head-and-shoulders shape.

.. see the images in the next message .. oh dear I can't add any more images, there appears to be a per-thread or per user quota

if I use 'hole' on that highlighted section then the corner disappears, but the block is no-longer solid, you can see inside it, not good.

if I take that highlighted corner and extrude it down into the body of the block, it looks at first sight like it works, however the corner piece doesn't get shortened in the way that extruding it up lengthens it - and you end up with the faces of the corner and the faces of the rest of the body, overlapping. You can see if you go into face selection mode and hover over the pushed-in corner, selection flickers between face of the pushed-in corner and the face of the rest of the block. That artifact eventually starts to cause problems. Shame I couldn't attach that last image, it was illustrative.

So what I really want is a way to start with 3) and chop the 'shoulders' off to get an identical body to that in 2) where I started smaller and extruded the 'head' out.

[micheus]

About the attachments, we have a small room for that. It's most intended to attach small files like the dump files (log of acrash). I do recommend you to use the http://www.photobucket.com/ - then you can use the button in the post editor to access it.

About you problem, it look strange you are extruding a face to create a shape that you want to remove after.
Anyway, if I understood right what you need is to Dissolve [Back Spc] and then select the two vertex in the bottom - left of the removed faces and use Connect.
Try that.

[rols]

This was just a very distilled example, I'd actually been working on something for a while and ended up with a shape I needed to cut the corners off after previous operations, so I made this little test case.

I don't see a button in the post editor to attach URLs. I just dumped two JPGs to a domain I own.

Dissolve was one of the things I tried, this is what I get after I select the four faces of the corner I want to remove and dissolve them, it's a bit of a mess mess, it looks different from either side, from the front you can't see the inside of the back wall any more and there are bare edge lines, from the back there's an impossible face which joins 4 corners which aren't in a plane.

http://dotteddogsoft.com/AfterDissolve1.jpg
http://dotteddogsoft.com/AfterDissolve2.jpg

I couldn't find anything to connect there.

However you did give me an idea about individually dissolving vertices. I've found deleting more than one at a time has unexpected results. If I dissolve one vertex, then another, on the corner edge I get the corner chamfered off. If I then split the remaining face and, with a bit of calculation work out where that new edge needs to move to and use move absolute .. I get what I need.

http://dotteddogsoft.com/Stage1.jpg
http://dotteddogsoft.com/Stage2.jpg
http://dotteddogsoft.com/Stage3.jpg
http://dotteddogsoft.com/Stage4.jpg

That may not be the best way to do it, but at least it worked.

[micheus]

Did you see that selected vertex in AfterDissolve? If so, you were looking to the "bottom-left" vertex.
Select its respective vertex in the back side (the view you have in AfterDisdolve2) and then, in the context menu, select Connect.

That strange faces created after dissolve are a visual issue, that should disappear when you close the mesh you just opened.

[rols]

Sorry I missed your reply. Yes I finally managed to recreate the issue and connect does put the mesh back together. I'm not entirely sure I fully understand, but the more I play with wings the more I'm starting to get a picture of how the mesh works.

Thanks for all your help, a silly problem it was I know but working through it has been very instructive.