How to convert a cylinder into a tube?

[Anonymous]

As a way to educate myself on 3ds Max modeling, I have assigned me some tasks. The latest one is to create an object such as the one below.

I figured out what seems to be the easiest way: A tube plus a taper modifier.

Now, I would like to learn how to do it in another way, by starting with a solid cylinder/cone and digging a hole into it (extrusion? face extrusion?).

TIA

[leeminardi · Accepted solution]

There are many ways. Here are 2 more.

1.  Use ProBoolean to subtract a smaller diameter cylinder from the original cylinder.

2.  Convert the cylinder to an editable poly and then select the top edge and use extrude to make a concentric shape then move the center polygon down.

[Anonymous]

Good. I am making progress but still have some conceptual things to grasp. Conversion to editable polys is one of them.

It seems that ProBoolean works on solids and therefore the conversion to editable poly is unnecessary.

Is there a way to know when some element is already an editable poly? The "Properties" dialog does not seem to know this attribute.

Another question: when you said "then move the center polygon down." are you referring to using the gizmo/arrow and manually pulling the concentric shape down? I was hoping to use modifiers.

Thanks,

-Ramon

[leeminardi · Accepted solution]

It seems that ProBoolean works on solids and therefore the conversion to editable poly is unnecessary.

I listed two independent approaches.   The first was to use Booleans.  It did not specify a conversion to Editable Poly.  The second method required converting to a Editable Poly.

Is there a way to know when some element is already an editable poly? The "Properties" dialog does not seem to know this attribute.

Select the object and go tho the Modify panel.  It should indicate the type of object.

Another question: when you said "then move the center polygon down." are you referring to using the gizmo/arrow and manually pulling the concentric shape down? I was hoping to use modifiers.

Yes, make the Polygon sub-object active then select the polygon that is in the center and with Move active pull that polygon down.  The adjoining polygons will stretch to stay connected.

[Anonymous]

Lee:

I found yet another, similar way to "open a hole" inside a cylinder. I created a cylinder, cloned it leaving them in exactly the same space. Next, I reduced the radius of one of them. Finally, I applied the ProBoolean technique that you showed.

Thanks so much!

[bioclone_ax45 · Accepted solution]

My favourite way use to be take the faces where both holes are going to be, then just use inset, and then use extrude on the new polygons... I try to use some amount that makes both extrusions get closer, almost in the same space... later just remove the faces selected and weld all vertices of both sides into a single one.

Later can be used tesselate/turbosmooth to check the welding is ok.

[maucorr · Accepted solution]

convert to edtable poly, then delete the top and bottom faces end add a shel modifier.