See below On Sat, Oct 1, 2022 at 10:15 AM Andy Little via Discuss < discuss@lists.openscad.org> wrote: > > > > ---------- Forwarded message ---------- > From: Andy Little <kwikius@yahoo.com> > To: OpenSCAD general discussion <discuss@lists.openscad.org> > Cc: > Bcc: > Date: Sat, 1 Oct 2022 14:14:20 +0000 (UTC) > Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? > Basically translate and rotate your sheet so that the fold line lies > along the x axis. > Subtract one side of the sheet and then rotate what is left around the x > axis > Now put the bit you subtracted back and rotate and translate your sheet > back to where it was. > Bassically it's a sheet bending machine :) > This is the same technique that I used. But I was hoping there was a better way then what I did. My solution won't work if a part of the work arches over the fold line. Imagine a situation like the figure below (in 2D). I am using a "^" to show the fold line, and imagine I want to fold at the arrow by 45 degrees, which would make the left side bend in, and C could be closer to segment AD B+--------+C | | | | A+-----------------------D ^ | Fold point The problem is that if I subtract the right side, then fold the left side, and then restore the right, segment BC would be disconnected. Ideally, segment ABC would all belong to the "left" side and be folded together. But how to do that? Kevin > > > On Saturday, 1 October 2022 at 14:51:56 BST, Kevin Toppenberg < > kdtop3@gmail.com> wrote: > > > This is interesting. Thanks for the link > > I'll have to study it more > > Kevin > > On Thu, Sep 29, 2022 at 7:01 AM Andy Little via Discuss < > discuss@lists.openscad.org> wrote: > > > > > ---------- Forwarded message ---------- > From: Andy Little <kwikius@yahoo.com> > To: OpenSCAD general discussion <discuss@lists.openscad.org> > Cc: > Bcc: > Date: Thu, 29 Sep 2022 11:01:05 +0000 (UTC) > Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? > Here is an alternative way, recursive fold... > > Folding a sheet material in OpenSCAD > <https://gist.github.com/kwikius/4bdd28fd10dccc54ac6c5cc597aed6d9> > > Folding a sheet material in OpenSCAD > > Folding a sheet material in OpenSCAD. GitHub Gist: instantly share code, > notes, and snippets. > <https://gist.github.com/kwikius/4bdd28fd10dccc54ac6c5cc597aed6d9> > > > > On Thursday, 22 September 2022 at 03:58:43 BST, Kevin Toppenberg < > kdtop3@gmail.com> wrote: > > > Joe, thank you for the offer. Let's see if I can do it in OpenSCAD. > :-) > Kevin > > On Wed, Sep 21, 2022 at 8:15 PM Joe Greene <volgclawtooth@gmail.com> > wrote: > > Bah silly phone.. I meant to add I am no Montroll, but have been doing > origami since the mid 1980's and have designed a few such patterns > > On Wed, Sep 21, 2022, 19:09 Joe Greene <volgclawtooth@gmail.com> wrote: > > I don't know about an app that'd do the unwrap but if you sent me a model > I can manially unwrap it in say Blender and send you back a pattern > > On Wed, Sep 21, 2022, 06:36 Kevin Toppenberg <kdtop3@gmail.com> wrote: > > Hey all, > > I often use OpenSCAD to generate models as patterns for real-life objects > I plan to make. I am currently needing to make something out of sheet > metal, and the shape will be mildly complicated: It will be a > chip-catching pan to attach to a metal-cutting lathe. I can't find any > sample pictures, but imagine a wall about 3 feet tall behind the lathe and > then folding around under the lathe in a sort of half-shell manner. > > I am certain that OpenSCAD can be used to make such models and to then > "unfold" them to get a flat pattern which would then be copied to the real > piece of sheet metal. But I am wondering if anyone has done this before? > Has anyone made a library and figured out the best way to generalize this > problem? > > This YoutTube video (https://www.youtube.com/watch?v=fWG-FPWj8JU) shows > how Fusion360 provides this feature. I just skimmed the video so I didn't > get too deep into its details. > > Any thoughts? > > Thanks > Kevin > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > > > ---------- Forwarded message ---------- > From: Andy Little via Discuss <discuss@lists.openscad.org> > To: OpenSCAD general discussion <discuss@lists.openscad.org> > Cc: Andy Little <kwikius@yahoo.com> > Bcc: > Date: Thu, 29 Sep 2022 11:01:05 +0000 (UTC) > Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org > > > > ---------- Forwarded message ---------- > From: Andy Little via Discuss <discuss@lists.openscad.org> > To: OpenSCAD general discussion <discuss@lists.openscad.org> > Cc: Andy Little <kwikius@yahoo.com> > Bcc: > Date: Sat, 1 Oct 2022 14:14:20 +0000 (UTC) > Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

I'm not quite sure what you are trying to do in your example. Do you want to fold segment AD while leaving the rest of the model alone? Or do you want to fold somehow the whole model at the marked point on AD? I don't understand how to do that. If it's the former thing you want to do, you could conceivably subtract the halfspace starting epsilon above AD and subtract the halfspace starting epsilon below AD, fold AD, and then union the subtracted portions back in. That would let you fold even if part of the model is both above and below the fold line. You could also require the fold specification list to specify bounds that could be used, or the need for 1-sided or 2-sided bounding, so this extra complexity is only used when needed. On Sat, Oct 1, 2022 at 1:18 PM Kevin Toppenberg <kdtop3@gmail.com> wrote: > See below > > On Sat, Oct 1, 2022 at 10:15 AM Andy Little via Discuss < > discuss@lists.openscad.org> wrote: > >> >> >> >> ---------- Forwarded message ---------- >> From: Andy Little <kwikius@yahoo.com> >> To: OpenSCAD general discussion <discuss@lists.openscad.org> >> Cc: >> Bcc: >> Date: Sat, 1 Oct 2022 14:14:20 +0000 (UTC) >> Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? >> Basically translate and rotate your sheet so that the fold line lies >> along the x axis. >> Subtract one side of the sheet and then rotate what is left around the x >> axis >> Now put the bit you subtracted back and rotate and translate your sheet >> back to where it was. >> Bassically it's a sheet bending machine :) >> > > This is the same technique that I used. But I was hoping there was a > better way then what I did. My solution won't work if a part of the work > arches over the fold line. > Imagine a situation like the figure below (in 2D). I am using a "^" to > show the fold line, and imagine I want to fold at the arrow by 45 degrees, > which would make the left side bend in, and C could be closer to segment AD > > B+--------+C > | | > | > | > A+-----------------------D > ^ > | Fold point > > The problem is that if I subtract the right side, then fold the left side, > and then restore the right, segment BC would be disconnected. > > Ideally, segment ABC would all belong to the "left" side and be folded > together. But how to do that? > > Kevin > > > > > >> >> >> On Saturday, 1 October 2022 at 14:51:56 BST, Kevin Toppenberg < >> kdtop3@gmail.com> wrote: >> >> >> This is interesting. Thanks for the link >> >> I'll have to study it more >> >> Kevin >> >> On Thu, Sep 29, 2022 at 7:01 AM Andy Little via Discuss < >> discuss@lists.openscad.org> wrote: >> >> >> >> >> ---------- Forwarded message ---------- >> From: Andy Little <kwikius@yahoo.com> >> To: OpenSCAD general discussion <discuss@lists.openscad.org> >> Cc: >> Bcc: >> Date: Thu, 29 Sep 2022 11:01:05 +0000 (UTC) >> Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? >> Here is an alternative way, recursive fold... >> >> Folding a sheet material in OpenSCAD >> <https://gist.github.com/kwikius/4bdd28fd10dccc54ac6c5cc597aed6d9> >> >> Folding a sheet material in OpenSCAD >> >> Folding a sheet material in OpenSCAD. GitHub Gist: instantly share code, >> notes, and snippets. >> <https://gist.github.com/kwikius/4bdd28fd10dccc54ac6c5cc597aed6d9> >> >> >> >> On Thursday, 22 September 2022 at 03:58:43 BST, Kevin Toppenberg < >> kdtop3@gmail.com> wrote: >> >> >> Joe, thank you for the offer. Let's see if I can do it in OpenSCAD. >> :-) >> Kevin >> >> On Wed, Sep 21, 2022 at 8:15 PM Joe Greene <volgclawtooth@gmail.com> >> wrote: >> >> Bah silly phone.. I meant to add I am no Montroll, but have been doing >> origami since the mid 1980's and have designed a few such patterns >> >> On Wed, Sep 21, 2022, 19:09 Joe Greene <volgclawtooth@gmail.com> wrote: >> >> I don't know about an app that'd do the unwrap but if you sent me a model >> I can manially unwrap it in say Blender and send you back a pattern >> >> On Wed, Sep 21, 2022, 06:36 Kevin Toppenberg <kdtop3@gmail.com> wrote: >> >> Hey all, >> >> I often use OpenSCAD to generate models as patterns for real-life objects >> I plan to make. I am currently needing to make something out of sheet >> metal, and the shape will be mildly complicated: It will be a >> chip-catching pan to attach to a metal-cutting lathe. I can't find any >> sample pictures, but imagine a wall about 3 feet tall behind the lathe and >> then folding around under the lathe in a sort of half-shell manner. >> >> I am certain that OpenSCAD can be used to make such models and to then >> "unfold" them to get a flat pattern which would then be copied to the real >> piece of sheet metal. But I am wondering if anyone has done this before? >> Has anyone made a library and figured out the best way to generalize this >> problem? >> >> This YoutTube video (https://www.youtube.com/watch?v=fWG-FPWj8JU) shows >> how Fusion360 provides this feature. I just skimmed the video so I didn't >> get too deep into its details. >> >> Any thoughts? >> >> Thanks >> Kevin >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> >> >> ---------- Forwarded message ---------- >> From: Andy Little via Discuss <discuss@lists.openscad.org> >> To: OpenSCAD general discussion <discuss@lists.openscad.org> >> Cc: Andy Little <kwikius@yahoo.com> >> Bcc: >> Date: Thu, 29 Sep 2022 11:01:05 +0000 (UTC) >> Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> >> >> >> ---------- Forwarded message ---------- >> From: Andy Little via Discuss <discuss@lists.openscad.org> >> To: OpenSCAD general discussion <discuss@lists.openscad.org> >> Cc: Andy Little <kwikius@yahoo.com> >> Bcc: >> Date: Sat, 1 Oct 2022 14:14:20 +0000 (UTC) >> Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

On Saturday, 1 October 2022 at 18:17:28 BST, Kevin Toppenberg <kdtop3@gmail.com> wrote:  

On Saturday, 1 October 2022 at 18:17:28 BST, Kevin Toppenberg <kdtop3@gmail.com> wrote: See below On Sat, Oct 1, 2022 at 10:15 AM Andy Little via Discuss <discuss@lists.openscad.org> wrote: ---------- Forwarded message ---------- From: Andy Little <kwikius@yahoo.com> To: OpenSCAD general discussion <discuss@lists.openscad.org> Cc:  Bcc:  Date: Sat, 1 Oct 2022 14:14:20 +0000 (UTC) Subject: [OpenSCAD] Re: OpenSCAD sheet metal origami? Basically  translate and rotate your sheet so that the fold line lies along the x axis.Subtract one side of the sheet and then rotate what is left around the x axis Now put the bit you subtracted back and rotate and translate your sheet back to where it was. Bassically it's a sheet bending machine :) This is the same technique that I used.  But I was hoping there was a better way then what I did.  My solution won't work if a part of the work arches over the fold line.Imagine a situation like the figure below (in 2D).  I am using a "^" to show the fold line, and imagine I want to fold at the arrow by 45 degrees, which would make the left side bend in, and C could be closer to segment AD B+--------+C  |        |  |         |A+-----------------------D       ^      | Fold point The problem is that if I subtract the right side, then fold the left side, and then restore the right,  segment BC would be disconnected. Ideally, segment ABC would all belong to the "left" side and be folded together.  But how to do that? Kevin Hi again, (Apologies for not pruning previous messages! Hopefully this one will be better)  I haven't thought it through but maybe as the mask you could use a very slightly scaled up version of the part you previously folded. But as I say... not really thought it through that well !