UnrollSrf Help

Hello, I am trying to draw on piece of plate steel that I then export using the unroll command. This 1 piece of steel should be 1 object however the unroll command is exporting 4 different objects. Not a problem but easily gets out of hand with 50+ objects.

How can I get this just to export 1 object instead of 4




Here you can see where it creates 4 different objects

Thanks in advance for the help

What do you mean by “export” using UnrollSrf?

Your object has 5 surfaces. UnrollSrf is unrolling each surface. That is how it is intended to work

G’day @flashc5 ,

Unless you want to make a box, you can/should only unrollsrf an open surface or open polysurface with explode = no.

Unrollsrf is not designed to unroll steel plate with the thickness modelled. Use a single face or a mid-plane (or some other representation) of the real plate as the input for unrollsrf.

Unrollsrf at your planarsrf stage is what you’re after in your example.


Thank you for the reply. Is there something that i should be using besides unrollsrf that would only extract the one plane? I export this out to dxf into another program that does the tool pathing.

Not in Rhino, unless you want to create your own plugin.

Hi -

It’s not completely clear to me what you are trying to do.
Do you need to model the objects with thickness?
If you do, you could use the ExtractSrf command to extract the surfaces that you need to export.

I need to export the flat pieces (2d) to a dxf so I can physically cut them out. I need to draw them in 3d so that I have the edges correct. A good example, lets say you have a cube that is 10x10x10 made out of 1/2" steel. It is not as easy as just cutting (6) 10x10s because of where the edges come together. Some of the inside pieces will be 9" (for the 1/2" on each side) in order to make this an actual 10x10x10

I need to take in account for this 1/2" but when I draw in 3d (because that is how it is in real life) but when I export, I only need the flat 2d (dxf) drawing. The example of a cube is quite simple but when you get into more complex shapes, it gets much more difficult to handle. Everything I do is flat work (sheet metal) that eventually turns into a 3d object (made up of cut/welded sheet metal)

Thanks for those details.

Yes, in this case you’ll need to use ExtractSrf to manually copy the surfaces that you need.