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Re: Better self-replicating through 'flexonics' - 16 years ago
... i emailed John Canny (the Prof. behind flexonics) if he have some more actual infos or is interested in participating ... 'Soft' mechanical systems in comparison to 'rigid' ones are more interesting when you go down in the micro- and nano-scale, as you can't reduce the sizes and accuracies of bearings and other mechanic and electromechanic elements under a specific limit - either the costs rby VDX - General
Re: Questions about the stepper motors - 16 years ago
... ah, got the point ... When it's possible to perform single steps, then you can measure the voltage of every output-pin (or the coil-polarity) per step and draw a stepping-matrix. So you can check whether the coil-driving works in the right mode or if two coils are bridged ... Viktorby VDX - Controllers
3D fabric - 16 years ago
Hi all, ... what's about string-fabbing-methodes like weaving, knitting or crochetting 3D-objects with strings and FDM- or glue-dots? As you can get thin and thick strings on big coils, it should be possible to design a weaving toolhead, which connect the string not only in a plain sheet, but in 3D and complex arrangements. With a bit optimizing with a glue-dispenser for fixing dots or integraby VDX - Plastic Extruder Working Group
Re: Better self-replicating through 'flexonics' - 16 years ago
Hi Sebastien, ... this is the main point in my interest in parallelkinematic systems and the discussions in the threads "Artificial Muscles" and other related too ... I already developed and built some flexure-structures for micro-grippers and nanopositioners with piezo-actuators and hydraulic or magnetic driving. With some other micro- and nano-mechanic setups i can drive and move makroscopicby VDX - General
Re: Questions about the stepper motors - 16 years ago
Hi Reece, ... best way for adjusting driving direction should be an inverter and an jumper for selecting 'normal' or 'inverted' direction ... And for your Z-motor: - look if the DIR-signal changes polarity in CW or CCW mode. If not, then trace the conections - if yes, then it's something wrong with the adressing of motor-coils ... Viktorby VDX - Controllers
Re: Reprap on CRN - 16 years ago
... hm ... the 'Omega-Point' until 2020 ... This time-scala would outrun most 'optimistic' visions of the 'pure nano'-thinktanks by three decades, so the possible acceleration by including the reprap-comunity in the evolutionary path seems to bring very much speedup Viktorby VDX - General
Re: metal laminates fabrication - 16 years ago
Hi Bob, ... if you want to rotate with 30.000 rpm and have a diameter of the unit of 1,5m then casted objects may be much to 'brittle', so they shurely would rip apart when rotated at this speeds! With laminating you have to select the right materials too, AFAIK in the beginning of electrification aera most heavy problems in powerplants were malfunctions when vibration breaks the bearings and tby VDX - Plastic Extruder Working Group
Re: What about the use of UV glues and UV light - 17 years ago
Hi Robert, ... we use a DELO-UV-lamp and Glass-Bond-glue (sometimes other UV-cured glue-types and pastes too) for prefixing thin wires on aluminium or glueing glass-parts and mirrors on glass- or metall-plates. It works very good and fast, the curing lasts 5 to 20 seconds until the glue is complete hardened ... But it's very expensive - the UV-Lamp is nearly 3000 Euros with an estimated lifetiby VDX - Polymer Working Group
Re: Beads Instead of Teeth? - 17 years ago
... look here, maybe some more ideas and hints for fabbing and connecting: Viktorby VDX - General
Re: Need advice please - 17 years ago
Hi Anthony, ... the actual extruder is capable of nearly 0,5mm (eventually 0,3mm) thick trays from melted plastic, so it's the actual detail-size. As comercial FDM-printers are capable of 0,2mm to 0,1mm thick traces and other types can output until 0,03 mm wide and 0,02 mm high droplets, this would be the goal to go with the reprap too ... One major limitation of the present system is the lackby VDX - General
Re: Inkjet-based 3D printing resources - 17 years ago
... here you can find some nice hacks for salvaged ink-jets: And for the basics and building on my own i got the book "Inkjet Applications" by Matt Gilliland: - here i have the complete specs, needed electronics and programming samples for the HP51604A/5R/5B ink-jet-cartridges ... I think using this infos to make some experiments with SIS-fabbing (=Selective Inhibition Sintering), where i simby VDX - Powder Printing and Selective Laser Sintering
Re: Furfuryl Alcohol resins (and Waterglass stuff too it seems 
) - 17 years ago
Hi Sebastien, ... yes, it was a sort plaster of paris with some additives for better volume-control ... Ink-head-forum sounds good, i have the schematics, background and some code to control an HP-ink-head - with time i'll go in ILS-fabbing or so ... Viktorby VDX - Polymer Working Group
Re: Self-fluxing Enameled Wire? - 17 years ago
Hi mimarob, ... i soldered my wire-wraps sometimes too, so it's not so a big difference for me. When home, i'll look around if i can find some examples of wire-wrap without and with soldering ... Why not trying to reprap some test-boards with integrated combs and for wire-separation and better organizing again rats-nests? This could be a sort of revival for the wire-wraps Viktorby VDX - General
Re: Servo motor VS Stepper motor - 17 years ago
Hi Andy, ... for another project (the "c't-bot") i manufactured index-plates for position-encoding of the bot which is driven by high-quality DC-gearbox-motors per PWM. Here some images: Milling and lasercutting the index-plate: Attached to the wheel: Assembled with the sensor-PCB's: With the same principle you can measure/control your motors too (either servos or steppers) The c't-bot hby VDX - Mechanics
Re: Servo motor VS Stepper motor - 17 years ago
... in my Tripod i have small sized stepper-motors with a magnet atached to the backside-shaft and some extra coils for tachometer-sensing ( ) but i didn't actually use them - so you can easily control your actual position in coarse ... Viktorby VDX - Mechanics
Re: Furfuryl Alcohol resins (and Waterglass stuff too it seems ) - 17 years ago
... update: I tried with solving and melting gelatine befor mixing with waterglass - it's more gelatine (elastic) then silicate and stays a bit brittle, but i used some gelatine with citric acid inside, so the reaction was at sudden (yes, acidic additives force the silicate to fall out). Then i tried with mixing plaster and other powders with sometimes interesting effects - some powders (pure cby VDX - Polymer Working Group
Re: Self-fluxing Enameled Wire? - 17 years ago
Hi Steve, ... it's the 'stone-old' principle of Wire-Wrap - long before you could by bread-boards and PCB-prototyping and -making was really easy there was this kind of prototyping (and sometimes for small series too). You could then buy isolated wire-coils, IC's with special longer pin-legs, pin-grids, plastic-combs for organizing the wires and other stuff for this job. The main tool was a soby VDX - General
Re: metal laminates fabrication - 17 years ago
Hi Bob, ... for cutting steel you need powerfull lasers - common used are Nd:YAG-lasers with some hundreds until some thousand watts. The 0,1mm-foil we cutted with a marking-laser with 60Watts max. power with a min. spotsize of 50 microns. When cutting thicker material you need more power and then you mostly have lasers with poorer optical resonanz and so a bigger spot-size too - for this mostby VDX - Plastic Extruder Working Group
Re: Extruder Rate (request for crackpot ideas) - 17 years ago
Hi Forrest, ... i remember a thread with a copy-mill - someone tried to run two extruders in parallel already? It's maybe an idea to build a longer bed and 8 extruders in parallel (or even more), so you can fab 8 (or less with malfunctions) equal objects in the same time, as a single extruder needs for one ... Viktorby VDX - General
Re: Other heatresistant materials - 17 years ago
Hi Fernando, ... i'm on CNC-milling because i need accuracies down to 50 microns with parts in sizes of some centimeters, what isn't practicable with molding or sintering. But for coarser parts molding is much cheaper and you can make series, so it's a nice to have method when rethinking/redesigning the extruder-head ... Viktorby VDX - General
Re: Furfuryl Alcohol resins - 17 years ago
Hi Fernando, ... i'll land here with the next posts The basic-structure of the waterglass-mixtures is dependant of the powder - with glass-powder i have a white paste, which dries to solid with the finish of the powder-granulity. When heating the paste with H2O2-flame to melt the glass, it behaves as normal - went black, then brown, then yellow and at over 800by VDX - Polymer Working Group
Re: Live CD - 17 years ago
Hi Reece, ... when it's to big for a single CD, then why not create 3 of them? 1. RepRap-demo-live-CD - all programs for running the reprap from boot, able of reprapping STL's from USB ... 2. Designer-live-CD - all programs for creating 3D-data and STL-files, able of writing to USB ... 3. Tools-and-PCB-creating-live-CD - all programs for designing PCB's and lots of usefull stuff ... So everyby VDX - RepRap Host
Re: Ultimate Rep Strap - 17 years ago
... good idea and faster to engrave then solid aluminium. I have some bigger sized 3mm thick sheets in my stock, so i'll try when the stronger millhead is there (in January or February) ... Viktorby VDX - Mechanics
Re: metal laminates fabrication - 17 years ago
Hi Bob, ... i made this with laser-cutted 0,1mm-steel-foil: I previous made some tests with milling the foil, what went fine too, but laser-cutting was much faster and with sharper/filigraner contour-details (and in this episode for free ), so i'll prefer lasercutting ... Viktorby VDX - Plastic Extruder Working Group
Re: Other heatresistant materials - 17 years ago
Hi Jay, ... this is the job to do in 'new types of extruder-heads' Actually i point on the PTFE-barrel, which could be replaced, so some 'low-temp'-alloys or -glasses, that melts between 300by VDX - General
Re: Extruder Rate (request for crackpot ideas) - 17 years ago
... and one for sugar and another for milk too ... Viktorby VDX - General
Other heatresistant materials - 17 years ago
Hi all, ... for housing and embedding high-temp-sensors i searched methods and materials, that can be milled and withstand temperatures over 500by VDX - General
Re: Extruder Rate (request for crackpot ideas) - 17 years ago
Hi Bob, ... for 3D-fabbing "Tea, Earl Gray, hot" you mustn't wait 300 years: Imagine a Darwin-two-head-extruder in a refrigerator-housing - one head extrudes a cooled ceramic-paste for the cup-slices and the other extrudes frozen Earl-Grey to form the 'Tea'-slices ... When ready after some hours put it in a microwave-oven, heat it until the ceramic sinters and the tea boils - voilby VDX - General
Re: Furfuryl Alcohol resins - 17 years ago
Hi Fernando, ... i experimented with Natron-waterglass for ceramic-like solids - it's a longer way then planned, as i didn't get the wished materials in time ... Today i experimented with materials i found in my basement and found some, that can work as support for extruding overhangs - all products stay brittle with a not so strong contact to the surface, so easy to remove ... 1. waterglass wby VDX - Polymer Working Group
Re: Servo motor VS Stepper motor - 17 years ago
Hi Joe, ... i worked over a long time with steppers in my different CNC-mills and in some homebrewed and a 'professional' laser-plotter i developed some years ago - with the right 'overdesigning' of the steppers (as made in most systems on the market) there is a fair range of possible speeds and loads, until the system begins loosing steps. With my actual CNC-mill-repstrap i run in halfstep (iby VDX - Mechanics