Not sure if this is the right area, since this a new area of exploration in CAD for me.

But current project is a round tube with holes and whatnot in it.
I'd like to 'unroll' it into a flat 2D file I can print and then wrap around the tube as a cutting template.

And I guess would be more or less same tool/procedure for unfolding a box?

Thanks

PunchCAD won't flatten trimmed cylindrical surfaces as trimmed NURB surfaces, MPSchmied's right, but you can convert them to mesh and it will flatten that into the pattern you want. Not as accurate in terms of decimal places, but as usable in most circumstances, and bear in mind that ViaCAD has polyline print output, not curve, anyway, and mesh flattening is unstoppable when NURB fanciness is fussiness. PowerPack will flatten other general ruled surfaces, it's trimmed cylindrical faces that it chokes on. TurboCAD Platinum will flatten, unfold in its terms, cylindrical and conical surfaces, and it can unroll logical cylindrical bent solids with neutral depth calculation. There's an inexpensive program called UltimateUnwrap3D that's predicated on UV mapping for game assets, and it flattens meshes as well as anything I've seen. Open-source FreeCAD has an add-on macro tool to unroll ruled surfaces, I've used it for lofted and edge-trimmed ruled surfaces but I haven't tried it with internal trims. There's a maritime program called ProSurf3 that the creator, Steve Hollister, is giving to people to use at no cost. It dates to Win 98, so it's got a dated/old-school interface, but don't be deceived by that, it flattens NURB surfaces with cutouts really well, even giving some indication of expandability, or how well a lightly compound curve surface might work. Steve's at newwavesys.com or Pilot3D.com contact details.

Does it flatten meshes made from compound-curved surfaces imported from CAD, DP?

3d-coat does not have special flattening tools. Maybe only "Relax" or "Strip to straight line".
But the quality of unwrapping of complex objects depends on the proper location of the seams. 3d-coat has enough tools for this.
I always used to unwrap rather simple objects like this paper cup above.

I did say meshes, yes, but they can be mesh representations of any surface, not only strictly developable or ruled surfaces, and it gives clear indication of where tears are needed to expand compound-curved equivalent surfaces. PowerPack/Shark Pro's unroll/unfold meshes is also good, but you have to manage keeping track of the facets that it's already flattened because copies remain in original orientation, while UUWrap moves them from their original orientation to the flattened plane, which is tidier and coherent.

Edited by user Wednesday, July 1, 2020 8:45:33 PM(UTC)  | Reason: Not specified