FreeCAD's mesh workbench also has analysis and repair, manual, auto and reiterative auto.by murrayd - General
Patents are good for 20 years max, stereophotolithography laser/photopolymer device patents lapsed in the early 2000s. Patents are intended to give a time-limited monopoly, not to illustrate or demonstrate. US corporate patent lawyers have been trying to manipulate extensions beyond that for fifty years, recently they'd been agitating for the extension of pharmaceutical and biotech IP under theby murrayd - General
The spool is winding onto the screw thread as the line is winding. The spool is walking, the line is stationary, the thread pitch is the thickness of the line. Video to follow.by murrayd - General
The sketch I posted showing a direct drive arrangement above has the spool winding on and off a machine screw thread with the pitch the same as the thickness of the cable, so the line doesn't "walk" as it winds on and off, remaining parallel with the guides and pulleys.by murrayd - General
QuotePawan Which is better a timing belt or a fishing line? There was a bit of conversation about what could be done with braided fishing leader cables back then: My old sketches still work, too.by murrayd - General
Punch/Encore's ViaCAD Pro and Shark FX CAD programs have a pretty neat plug-in called Power Pack Pro that's still in beta. Amongst its 3D printing-directed features is the capability to convert mesh/facet models back into NURB solids and surfaces and "analytic" shapes, planes/n-gons, cylindrical/conical surfaces and sections, and ellipsoidal surfaces. It's been done before by high-end stuff likby murrayd - 3D Design tools
Disappointing that 3DS, who feel they've got an issue with Formlabs infringing their patents, are suing Kickstarter for 'promoting' the infringement. I find it pretty amazing that people can be sued for being party to an 'infringement' without the 'infringement' having to be established first. Isn't that the actual definition of 'prejudice'?by murrayd - General
If the model's an aggregated cluster of .stls, Netfabb has the capacity to boolean them into one object, which ought to solve the problem. Freecad and other CAD programs can do the same for other formats.by murrayd - 3D Design tools
Intersect the extrusion (assuming that, when you say 'extrusion', you mean that the vectors have been thickened, shelled or offset, depending on modeling SW, so that the artwork extrusion has volume) with a sphere, then apply chamfers to model blade edges. G-code is generated from the model, as with reprap printing.by murrayd - 3D Design tools
I worked in commercial molding, and the extruders that normally extruded PVC, HDPE, or PP were purged with LDPE then left to cool. When they're heated the next day, the LDPE plugs are easily purged themselves, by fresh PVC or whatever.by murrayd - General
Zip ties? You have zip ties? I reach reflexively for tie wire that can also keep plants upright and seals freezer and garbage bags. I also keep a stock of a couple of cards of those mounts that spinster ladies use to hang their royal family commemorative dinner plates on the wall. They're just edge clips held by long tension springs (the useful bits) that can be cut down or strung together toby murrayd - General
A process with FreeCAD. Import the .stl, select it and use menu part>create shape from mesh, then select the shape and go to menu drawing>project shape. A palette will open with a bunch of options, you can experiment with them to find the result you want and press OK, a 2D projection will be on your screen. You can select it and go to menu drafting>downgrade, this will ungroup the linby murrayd - 3D Design tools
Modeling with history with a GUI is graphical scripting, progressive rather than having to declare it before anything can happen. You can copy and reorder, replace, suppress and express, define and create associations and dependencies without having to know the Hogwarts incantations. "Constructivus Solidicus Geometricus!"by murrayd - General
Pretty much any CAD system can, GUI or not. I've no nostalgic affection for command lines and syntax rules, retracing (drafting pun warning) that ground is unappealing.by murrayd - General
I capitulate! I was describing reversing an .stl back to CAD solid, but I can agree that hole clearance is a trap.by murrayd - General
That's not right. A 3mm screw won't fit through a polygon that's circumscribed by a 3mm circle. The clearance circle is circumscribed by the polygon, not the other way round.by murrayd - General
KeithSloan Wrote: ------------------------------------------------------- > OpenSCAD is fine if you like programming. Some of > us do NOT and would prefer to use 3D cad software So true. That being said, FreeCAD can turn an .stl part into a CAD solid. Import the .stl, and select it in the file tree, go to the part menu and select "create shape from mesh". This'll bring up a tolerance dby murrayd - General
Cathy Lewis was CEO of Desktop Factory, which was a startup developing a machine that used a halogen lamp to fuse layers of polymer powder onto a transfer roller. They took $500 deposits, and it was supposed to be delivered at $5K. They ran out of venture capital and Ms. Lewis wound the company up, returned the deposits, sold the IP to 3DS and went to work with them along with a number of her Dby murrayd - General
I'm still building a repstrap with cable drives, and I posted these concept drawings a couple of years ago. With several wraps around the drive cylinder, there's no slippage and the amount of stretch means that the return pulley can be set up to accomodate the occasional adjustment, constant (spring) loading isn't needed. I started on this because the z drive only needs one screw because of tby murrayd - General
A Mendel, an Ultimaker and a Makerbot walk into a bar. The Ultimaker says to the Makerbot "Why do our kids look like him?"by murrayd - General
Six and more years ago, a guy named Justin Shumaker wrote and developed a program called Nurbana. It's a spline surface editor that used Rhino's.3dm format natively, as Moment of Inspiration does now. This was back about the time that Rhino V2 was released. Nurbana used a Blender-like interface. Justin stopped developing Nurbana when he left university and abandoned it, and I hadn't realisedby murrayd - 3D Design tools
Turbocad and Viacad both do the conversion, but of course they can't reconstruct curved surfaces from facets.. The difference between them is that Turbocad consolidates coplanar, contiguous facets into a single face. Viacad doesn't, but both perform booleans et al and give the same output once the conversion's been done.by murrayd - 3D Design tools
Not open source, but there's a fairly inexpensive convertor called Accutrans. It's a format translator that handles US geographic survey and other DEM data, builds meshes out of it, and translates to .stl or .dxf and others. Here:by murrayd - General
Happened to be working away with my own gadget and keeping an ear on Catalyst, the Australian ABC science show. The phrase "3D printing" attracted my attention, and there's Adrian demonstrating Mendel and explaining Reprap to Jonica Newby (isn't that the optimal name for a science reporter?). Adrian's daughter gives a case study of Reprap rescuing broken bits of her car (what sort of car is thaby murrayd - General
Version 5 beta just released has improvements like 2D .dwg sheet output, and correcting that unit/scale glitch. Doesn't dimension, but .dwgs can be dimensioned and edited in lots of free apps. It now imports IGES, can do a bit more with .stl imports, and has some new rendering ability.by murrayd - 3D Design tools
"the Information" is the title of James Gleick's latest book, and it's a fascinating read. It tells the story of humans (and other species) amassing and disseminating information, and arrives in the present with contributions from people like Richard Dawkins, whose conclusion is that biology is information consolidating and perpetuating itself. It has quite a bit to do with RepRap philosophy, iby murrayd - General
Viacad 2D/3D has a cheaper RRP than TurboCAD deluxe, probably costs slightly more if TurboCAD's discounted, but its modeling and exchange functionality is stronger and it uses history and associativity better. It has STEP, IGES and .stl exchange.by murrayd - 3D Design tools
There's a pretty inexpensive toolpath generator for 2.5D CAM called STLwork (www.stlwork.com) that comes bundled with another application called Accutrans. Accutrans is a format translator, but it has 3D text functions for TrueTypes built in which saves as .stl.by murrayd - General
Do you mean to extrude the lines of a sketch to make something stepped like a topographical terrain, or to convert a photo into a heightfield surface? If the latter, ZSurf4 is a program that converts a greyscale bitmap (any picture can be converted to greyscale in Paint, Zsurf's documentation explains it well) to an IGES surface. It's available here: Works very well, with the proviso that theby murrayd - 3D Design tools