Using shapebender for a curved apron

mrossk · 28 Oct 2010, 01:29

Hi- I've got a question regarding a curved apron that I want to shape. I can create a curved apron that fits precisely between two legs, and I can shape a straight apron, but how can I curve precisely a shaped part? I thought I would lay out the apron as a straight part, shape it, then perhaps use the "shapebender" plugin that Dave R showed on the FWW blog a while back. But I don't know how to get precise endpoints for shoulders. Does anyone know if that plugin can be used to get parts of a specific, precise size to meet two legs? Or have other suggestions? I imagine the "push/pull on a curve" plugin could work, or perhaps some complicated "intersect", but it seems like there should be an easier way. Thank you in advance,
Michael

Dave R · 28 Oct 2010, 01:49

Michael, you can use Shapebender that way. Drop me an e-mail and I'll be happy to help you out.

dermotcoll · 28 Oct 2010, 22:07

Dave I would love to see how this is achieved also. I have a project for a students union TV studio desk and they want a curved apron at the front with lights behind the apron shining down on their logo. The desk has to be a specific size so just would like to see your approach to this.

Dave R · 29 Oct 2010, 01:02

Dermot, I'll do something up to show you what Michael and I did.

brandy20 · 29 Oct 2010, 10:22

So, I suppose that most of us could be interested in this approach

Dave R · 30 Oct 2010, 02:05

Well, here's a quick tutorial for using Shape Bender. Let's see if it helps. I'm not saying anything about the design of the table. I just pulled the design out of my hat which I was sitting on. This isn't about the design though so I didn't agonize over that. If you click on the images you can see larger versions of them. Or maybe you'll want to see smaller ones instead.

SO after getting most of the undercarriage drawn, I started working on the geometry for running Shape Bender I drew a 48-sided circle centered on the table and on the ground plane. For the radius I chose the inside radius of the curved apron pieces. I rotated the circle 3.25° so that I have sides on the circle that are perpendicular to the faces on the legs. Depending on the thickness of the legs you might find that you need to use some other number of sides so that there are sides of the circle intersecting the legs at right angles. If the sides don't cross the faces of the legs at right angles, the ends of the bent apron won't meet the legs squarely.

Then I drew lines parallel to the sides of the legs to break the edge of the circle. Just to make them easier to see I drew them so they intersect but that's certainly not required. With Entity Info open, I selected the arc between the legs and noted its length. (To reduce the number of screen shots I left the circle but I would normally delete all but the arc I want to keep before bothering to look for the arc length.

Next I drew a line the same length as the arc. I put that line on the red axis although to make it easy to see for the screen shot, I've turned off the axes.

I drew a straight version of the apron so its length matches the length of the arc and the line. I made it a component and located the at the height above the ground plane where I want the bent one to end up. Also notice from the vertical guidelines, the apron component is positioned so its back face is directly above the straight line.

Now we're ready for the plugin. Select the component.

Get the tool and click the straight line as directed on screen.

Note that one end of the line is labeled 'Start" and the other, 'End'. the tool changes to indicate that you need to select the curve.

Normally the plugin draws a sort of skeleton of the component over the curve at this stage and the ends are labeled with Start and End. sometimes it doesn't draw the skeleton as in this case. I'm not sure why it doesn't but the plugin works anyway. The key thing at this stage is to make sure that the Start and End labels on both the line and curve are at the corresponding ends. If they aren't, hit the up arrow key to swap the labels on the curve.

Hit Enter and the curved component will be drawn. With the set up as I've done it, the bent component ends up in place so I don't have to move it into place. Fewer chances for error this way. Check the bent component for holes in the surfaces and fix those if they occur. The straight version of the component can be deleted unless you want it for dimensioning or for a pattern for a template or something.

And since this is an apron for a round table, Rotate/Copy the component and make the radial array.

See what you can make of that.

Anyone want a butt-ugly table design? I don't think I'll even keep that SKP file.

mrossk · 30 Oct 2010, 04:15

awesome Dave. very ninja. Thanks!
Michael

brandy20 · 30 Oct 2010, 12:01

Thank you very much Dave! The table isn't so bad but it could be "some kind of uncomfortable" to sit on there...especially on the borders, if you know what I mean...

dermotcoll · 1 Nov 2010, 17:49

Dave

Sorry for the late reply. As usual my friend you have come up trumps again!! Many Thanks.

utiler · 2 Nov 2010, 02:58

Hey thats cool Dave!!!