>> " you cannot understand and cannot modify and cannot analyze for potential improvements"
I suspect all of those assumptions are completely incorrect. The AI will have built a full part, from primitives, with the relations and sketches you would expect, probably named the features nicely too, so you should be able to understand it. You can analyse it using the normal FEA tools you would normally use ... and make improvements as you normally would with any other model someone provided to you. >> " But if the part is designed by an LLM, you have to start over; you can’t edit the existing files" I think you are completely misunderstanding how an AI creates the files ... it will be creating normal 3D CAD files just like a human would, except possibly better documented. You can edit them by hand just as if a colleague had produced them. On Tue, 6 Oct 2026 at 18:22, Chris Albertson <[email protected]> wrote: > So now with the LLM, you have a design for a chuck that you cannot > understand and cannot modify and cannot analyze for potential > improvements. It might even be a copy of a commercial product, and you’d > get sued if you tried to make these and sell them. You just don’t know > anything about how it was designed, and you can't justify any of the > decisions. > > The biggest problem is that you have lost control of the design of the > product. What if the part is too heavy or not strong enough or both? You > would not know until after you made the part, and then you ask the LLM to > fix it, and you are back to zero and can’t know what else is changed until > after you build the new part. > > Of course, OpenSCAD is very limited to only making one part, not a whole > machine. (Try my test where you make a battery-operated drill, let alone a > motorcycle engine.) > > Hand-written G-code is a problem too. Again, you can’t use it to > simulate a machine before you commit to manufacture. Can’t do any kind of > heat or stress calculation of G-code (or OpenSCAD). And far worse, is that > if you hand-write G-code there is an “air gap” between the design and > implementation. You can’t prove the as-built is the same as the > as-designed unless the part is very simple. A critical QC step is “air > gapped”. > > The biggest use of 3D CAD is “modeling”— the try before you build idea. > A machine or product usually has many off-the-shelf parts, screws and PCBs > and switches and LEDs and ball bearing units and washers and brass thread > inserts and 100 other kinds of hardware. All this has to go into the > model, and you have to check that all the parts mate. > > Then 6 months later, someone makes a change request, and you have to move > some internal PCB and wires by 5 mm. But if the part is designed by an > LLM, you have to start over; you can’t edit the existing files, so all your > product testing has to start from zero, again. > > > > > On Oct 6, 2026, at 1:15 AM, maurice e heskett <[email protected]> > wrote: > > > > On 9/30/26 22:34, Ryan McIntosh wrote: > >> Fusion360 runs just fine under WINE on linux. OpenSCAD will create > >> whatever level of part complexity you can mathematically describe. If > you > >> have a part with many b-splines or freeform curves, yes, you will spend > a > >> long time describing them. However, the mathematical precision with > which > >> you must think about your part can make the production of CAM files or > >> meshes much simpler and/or with less "stepping" It is worth mentioning > >> that FreeCAD exports to OpenSCAD natively. Should you want to produce a > >> part on an older Fanuc, for example, you may have difficulties with > larger > >> meshes. > >> > >> > >> *Ryan McIntosh* > >> E4F Designs > >> (204)770-3682 <(204)%20770-3682> > >> [email protected] > > Its likely good to know that fusion360 can do that. But the last time I > read the TOS and license I got a bad after-taste. Back to openscad for > printed designs, or writing my own gcode. Freecad to me has way too > vertical a learning curve, where openscad is a piece of cake. > >> On Wed, Sep 30, 2026 at 4:04 PM Chris Albertson < > [email protected]> > >> wrote: > >> > >>> My test to see if a CAD/CAM system is usable is to try to make a > Milwaukee > >>> battery-powered drill housing. Note that the drill on the outside > has > >>> no flat parallel surfaces, as it is all compound curves and freeform. > >>> Except there is bilateral symmetry and, in some places, radial > symmetry. > >>> Then, if you look on the inside, it is very geometric and has places > for > >>> mechanical gears and PCB mounting holes, threaded blind holes, and is > very > >>> “mechanical.” A good CAD system should allow you to design something > like > >>> a drill or a car that is both mechanical and a sculpted shape. > >>> > >>> FreeCAD is open source and passed the above test. Autodesk’s Fusion > 360 > >>> is free to use and has a better user interface and is faster to use. > Both > >>> have a CAM systems. FreeCAD’s CAM is really only 2.5D and basically > >>> works. Autodesk Fusion’s CAM is 100% professional quality, but the > free > >>> version is limited. You need a paid license for 5-axis support. Both > >>> work well for making 3D-printed parts with very complex part shapes up > to > >>> and including motorcycle engines and similar. > >>> > >>> About Gene’s comment: I can’t understand how someone with good > mechanical > >>> skill can not learn either of these two CAD systems. OK, Fusion 360 is > >>> easier. But anyone reading this should be able to do basic work after > a > >>> week or two of study and after 6 weeks, make complex parts like the > >>> Milwaukee drill. > >>> > >>> About OpenSCAD, I challenge anyone to make a Milwaukee battery drill in > >>> OpenSCAD. Or a car or a motorcycle engine. It is, however, good for > any > >>> shape that can be described by an algorithm; gears are a good example. > >>> > >>> Summary: if making complex parts and wanting a free CAD/CAM system, use > >>> Fusion 360. If it must also be open source, use FreeCAD. > >>> > >>> Your operating system might help you decide. Fusion 360 runs only on > >>> macOS and Windows. FreeCAD runs on these but also runs on Linux. > >>> Fusion360 can run on Linux if you run a virtual machine with Windows. > > > >>> On Sep 30, 2026, at 8:14 AM, maurice e heskett <[email protected]> > >>> wrote: > >>>> On 9/30/26 09:41, andy pugh wrote: > >>>>>> Agreed.. Off topic, is there a CAM that's both open src and free? > >>>>> FreeCAD? > >>>>> > >>>>> https://www.youtube.com/watch?v=mVz2p_ze3yc > >>>> A near vertical learning curve for my aging wet ram. I've made > probably > >>> 20 passes at it, haven't gotten past the 1st page of examples w/o > gaining > >>> any real insight as to how it works. Openscad is a piece of tasty > cake. The > >>> link above gave me a prostate commercial I had to sit thru, but got > bored > >>> after about 2 minutes and killed FF. Never saw the freecad demo. went > >>> back again, 'skip"ped about 3 commercials, then got lost in the > speakers > >>> accent. As Winston Churchill once said, 2 great countries separated > by a > >>> common language... The chances I'd get anything out of that are quite > slim. > >>>> Thanks, Gene > >>>> > >>>> > >>>> _______________________________________________ > >>>> Emc-users mailing list > >>>> [email protected] > >>>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>> ___________________________________________ > >>> Emc-users mailing list > >>> [email protected] > >>> https://lists.sourceforge.net/lists/listinfo/emc-users > >>> > >> _______________________________________________ > >> Emc-users mailing list > >> [email protected] > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
