Hi Demented, ... it's STL too, so borrowing isn't the point ... In the Tools/Objects i placed 3 STL-files for testing dimension - it's no problem to make our own reprap-specific objects around the 'tear-drop'-shape for example If you want something more specific, then mail me a sketch and i expand it to a reprapable STL-object ... Viktorvon VDX - Administration, Announcements, Policy
Hi Andrew, ... here a first shot ... With your setup and the measuring-convention from the image below i have this conversion for every X,Y-tupel: La = SQRT(X^2+Y^2) Lb = SQRT((Db-X)^2+y^2) Lc = SQRT((Db/2-X)^2+(Dc-Y)^2) So when you start in the middle, then you have to move through converting the relative X,Y-displacement in La,Lb,Lc-displacement (look for right +/- moving) for shortening anvon VDX - Mechanics
Hi Andrew, ... i'll send you the software, when it's functional (can take a while). When you need the formulas for XY-output in the plane, then i'll think it over, should be no problem, it's much simpler then my multi-angle-mechanic ... In the meantime you can try with emc/emc2 - here you can drive tripods too. The string-tripod is a very simple and easy to setup system, so you can play with evon VDX - Mechanics
... it's the principle of SLS (SelectiveLaserSintering) but it's heavy time-consumpting, to lay down the single trays with the extruder and melt them to solid (but i'll do it too for higher accuracy in the micron-area). Mostly you lay down a complete slice of powder and draw your paths with the laser as in a pen-plotter. Another concept is to heat a spot on the surface of your object and blow mvon VDX - Reprappers
... here i have three simple test-files - maybe someone can try to import and scale/place them in the working area, as my exporter isn't normed yet ... Viktorvon VDX - Let's design something! (I've got an idea ...)
... is someone interested in STL-files from Christmas-cookies, (as Star, Heart, Moon and so on) or other simple shaped 3D-objects to extrude from eatable pastes as chocolate, couverture or so? I can make some objects and post them here - or maybe in a special space for this kind of stuff ... Viktorvon VDX - Administration, Announcements, Policy
Hi Jared, ... it's possible to apply a 'linear POT' - a selfmade with wire wound on a stick and a glider can be made too. Or connect the shaft to a 10-turn-POT or sometihing else ... But the resoultion and so the positioning accuracy of the axes is mostly poor or with highly precise parts very expensive. Viktorvon VDX - Controllers
Hallo Leute, ... wenn Englisch als Forums-Umgangssprache eine zu grovon VDX - Altes Forum
Hi Colin, ... it's my experience with some individuals, i disputed about home-brewed-3D-fabbers in the last years. They argued with 'low-cost' (actually from 15.000 to 25.000 Euros) 3D-fabbers, already present in the market - as the EZPrinter (LOM), the printers from Dimension-printing, ZCorp and so on, which output 'perfect and usable' parts. Another counter-argument was the 'ready-to-assemblvon VDX - General
... a main difference to the time, when the Wright-brothers presented their planes is the actual presence of professional, fully developed 3D-RP-printers. So the reprap isn't a really new and exciting gadget, but 'only a coarse 3D-fabber'. This lowers a bit the excitement of the people, as some would say "Why invest time and money in this garbage-assembly, when perfect/better ones already therevon VDX - General
Hi BDolge, ... i agree fully - this is my personal path in developing: First bring to work my 3Axis-CNC-Repstrap (mostly for milling the complexer parts for the next developing steps) - then make some extruders and printheads (as for the CNC too) - and play around with different materials ... - then activate/realize the Tripod (only software left to do) ... - then activate the diode-laser forvon VDX - General
... i didn't have any problem with simple setups For me it's a good point too, to give a not so skilled individual the ability to build it without expensive tools and material in his basement in two weekend-sessions ... But as good way to evolving faster, i hope to seed some regional competence-centers - for example at scools, institutes or at home by some enthusiasts as me And here the highvon VDX - General
Hi guys, ... good luck and fast progress! I think my CNC-mill-repstrap will work in january or February, as i have to buy and exchange some expensive parts and a stronger mill-head to make some complex parts ... With the Tripod-demonstrator i'm on the elecronics and software, so it should be active in some weeks too. When the software runs properly, then i'll build a second one, capable of favon VDX - Reprappers
Hi Jim, ... it'll take some time, until reprapped cyborgs or such stuff would strife through your nightmares The main idea of the reprap is to make the fabbers cheap and common enough, so every interested could start with his or her own ... Until you can receive the kit from your friend, or give him one, the main goal should be to seed some 'competence-centers' at some locations, so it can spvon VDX - Reprappers
Hi Zach, ... then it's a good one With 8 wires it's your deal to drive it as uni- or bipolar, so the 'unipolar' was a bit misleading ... Viktorvon VDX - Mechanics
Hi Blerik, ... microstepping does add presision! If you drive your 200-steps-motor with half-steps, you receive 400 (nearly) accurate steps with positions inbetween the 'normal' 200-step-matrix - with 1/4 and 1/8 then ever more (Some companies sell 1/128-drivers too), so an 1/8-microstep-driver turns your stepper with 1600 discrete steps per turn! The absolute position isn't so absolutelly navon VDX - Mechanics
Hi BDolge, ... i already milled in plastic, aluminium and brass with a 0,3mm-diameter milling head, so for milling freefrom-holes in thin plates or aluminium/brass-heads it should be no problem too ... For the orientation: - think on 'tangential'-cutter-plotters, here the cutting knife is turned with a motor in the driving direction, so you have a clean cut exactly in the moving line, not a bitvon VDX - General
... first experiments with waterglass showed, that it's a perfect soluble/fixing for glass- and ceramic-dust, as it dries on air in minutes to a solid matrix, stiff enough to support aditional layers and could act as ready-to-use moulding-form without further curing or heating ... Baking in an oven cure the body to maximal stability - i didn't try with melting of soldering glass at higher tempervon VDX - Polymer Working Group
Hi Sebastien, ... look on the figures 4 and 5 in the paper Here is shown, how much preciser a parallelised scara-robot is, in respect to the serial setup ... Viktorvon VDX - Reprappers
Hi Demented, ... ah, clear - this is main the background of my faible for parallel-kinematics and 'bionic' or flexible/morphing actuators - here it's hard to bring the simulation to proper action, but relatively easy to build moving setups with bending and expanding arms activated by syringes or pressurised/expanded elastic hoses and bellows ... Viktorvon VDX - Reprappers
Hi Zach, ... there are two types of unipolar motors: the simpler ones have only 5-wires, where the coils are in the middle connected - here you can't wire as bipolar. The better ones have 6 wires (coil-middles separated) or even 8 wires (every coil separate) - here you can wire as uni- or bipolar. So when you have 6 wires, its OK; with 5 wires it shouldn't work really as bipolar setup, or youvon VDX - Mechanics
... you must think of the fabbing-time too ... If a decimeter-cubicle needs half'n hour (or even longer with better accuracy) to build, then a very big object with the same precision can eat weeks or months of time fabbing! And look on the material-amount and possible malfuctions in the support. For seriously speeding up the fabbing proces without losses in accuracy i hope to manage foil-lathevon VDX - Reprappers
Hi Demented, ... why? It's the way, i received most of my RP-models: - i constructed the parts in Lightwave or 3D-Studio and posted the STL-files to a comercial RP-company. Some days later i received the parts and send the bill to my boss I think it's a good idea to install some local reprap-copy-shops in towns, as many peoples, interested in the reprap-idea, aren't skilled or motivated enougvon VDX - Reprappers
Hi Zach, ... an unipolar motor isn't so easy used for microstepping, as most discrete drivers are designed for bipolar ones. So if you want to rise the accuracy in future designs, a bipolar motor should be better - look, if you can get the kelig motor in bipolar too ... Viktorvon VDX - Mechanics
Hi Jared, ... obviously the servo can do the same (and faster too!), but the driving of two steppers is simply clocking with a constant waiting time between steps or output single step-pulses until you reach the target-position, when a timer counts down. Servos needs much more software, as you have to control the moving-speed very accurate in respect to the actual position and the way the specivon VDX - Mechanics
... hmmm, sound like waste of energy and potential ... Maybe some of you remember the Golem-project, where your computer was embedded in a internet-grid to evolve robots, build from sticks, joints and rod-actuators. There was the possibility too to RP your favorite bot and apply some linear actuators, so he could act in real as in the simulation. Maybe this is a more fascinating way: you buildvon VDX - Reprappers
Hi Zach, ... it seems, that i have to work a bit harder to bring my PC in the status to run the host-software The fab@home-software is running and shows simulated building too, but the reprap-host didn't start ... Viktorvon VDX - Reprappers
Hi Fernando, ... i actually 'played' a bit with Natronwaterglass (water-soluble Alkali-silicate) and glass-dust. It seems to work as hoped - in the bottle/syringe it stays stable, on air it will dry in some minutes to nearly solid and with a H2O2-microflame i melted it without problems to solid glass - and there will only water fume out. At home i'll try with some other dusts and powders if itvon VDX - Polymer Working Group
Hi Demented, ... it's more a pressure-chamber, then an oven - i call it in german "Dampf-Kochtopf" or pressure-cooker, which is heated on an oven-plate ... With the right chemistry behind you can make all sorts of polymers from the right fractions. I think, with a more sophisticated physical infrastructure there would be simple carbon as building-material in future - think carbon-nanotubes, grvon VDX - General
... i have a ceramic-paste called "Karger keramische Vegussmasse", which dries at room-temp to a hard to remove but brittle solid and can be cured in the oven to behold a bit better, but stays brittle too. I think, it's simply ceramic-dust wuth waterglass too! We used this paste for embedding and covering high-temp-sensors for 500von VDX - Paste Extrusion Working Group