Hi Max, willkommen! Da lby VDX - Schwarzes Brett
Hi Marcel, willkommen an Bord Wenn noch ein paar Leute dazustoby VDX - Schwarzes Brett
... i get stuck to reprap and fab@home in last year and had some talks with Zach and Evan from f@h. It's obvious that the f@h-system is more mature and 'user-friendly' then reprap, but i bet on reprap, as here is much more 'live-evolving' and seemly endless potential, whereas f@h seems to be 'freezed' in its actual status. But beside, there is no need to flame or blame each other - why not partby VDX - General
Hi fifo2711, ... we had some talk about measuring the tooltip-position with tactile sensors or fixed cameras and such - maybe i'll find some of the threads later ... Viktorby VDX - 3D Scanners, Book Scanners, and Optics
Hi Demented, ... straight sine wave didn't sound so good - when you step in the range from some houndred Hertz to 1 kHz it should be more square maybe with some ripples in the beginning ... Which frequency can you count? Which motors (0,9by VDX - Controllers
Hi John, i think with the "tick and forget"-method moving the stepper is much easier then the close-loop with an encoder (when you didn't stall the stepper) In my CNC-mill i have motors with 200 steps per turn and a threading with 5mm per turn, so i have a resolution of 25 microns per full-step. My controller drives with half-step, so the resolution halfs to 12,5 microns. Now i'm on assemblinby VDX - Controllers
... isn't it a bit to much publicity for the actual status of the project? Some of the reports rouse expectations, that reprap can make anything (beside himself) in no time! Then its obvious, that this expectations will collapse and give a serious backdraft. Better give the development a bit more time, so we can sometimes meet the accuracy of common 3D-printers ... Viktorby VDX - General
... yep, i'm Viktor from Germany in respect to Vik from New Zealand Viktorby VDX - Controllers
Hi Daniel, ich habe ein ganz anderes Problem: Meine CNC-Frby VDX - Altes Forum
... a Stirling engine is much more complex than a couple of fused wires and would wear off by time, so a solid-state system with no need to further support and maintenance should be better. The poor efficiency of the Seebeck-elements should be a factor of the amount of them - combine 10x2 elements (10 hot + 10 cold) per solar mini-dish, arrange 20x20 of the dish-cavities in a panel of say 1x1 meby VDX - RepLab Working Group
Hi Eric, ... for a bot-project we used single optical-mouse-chips with an Atmega-Controller programmed in C and Java: (more images here, in my gallery: ) It's nearly the same solution, but our chip has a 19x19-sensor and too was 'misused' as camera: With a normal webcam you have much more resolution and simpler interfacing, but for singlechip-microcontrollers the 'mouse-camera' with the seriby VDX - Controllers
... sometimes i was thinking of a cheap'n'dirty home-brew solar-cell, which didn't work photovoltaic, but instead with heat from concentrating solar-mirrors. Simply connect two different metall-wires in respect of the electro-negativity (e.g. konstantan with iron) to make many small Seebeck-elments (=inverse peltier-elements). Then mold-make an array of small solar-fokussing mirrors (like an egby VDX - RepLab Working Group
Hi Sebastien, ... i've looked previously, as it would be handled in the other local forums - most started with english Ansonsten lasse ich es darauf ankommen Viktorby VDX - Schwarzes Brett
Hi mimarob, ... recently i read a tech-article, where someone managed to 'clean' carbonize any organic stuff as vegetables or household-droppings. He simply used a pressure-cooker filled with the vegetables, some water and citric acid as catalysator and heated this for 12 hours or so up to 120by VDX - Plastic Extruder Working Group
Hi Marcel, actually the best soure for the reprap-parts in Germany (or Europe) is When others complete their repraps/repstraps, this could change anyway ... For the lang-issue: - it's a sort of 'diplomacy' as we're on a mainly anglophone forum and most (passive) readers in the German RRUG are too ... *** Natby VDX - Schwarzes Brett
... you can use for good quality reducing high-count 3D-data and for 'skinning' dot-clouds with a surface to produce STL-data ... Viktorby VDX - 3D Scanners, Book Scanners, and Optics
Hi Demented, ... try to get an oszilloscope and then check the signals, timing and polarity and the curve-forms at the coils. Viktorby VDX - Controllers
Hi Bitman, for macroscopic dimensions it's much to slow, but when you want to build in mesoscopic dimensions (square-micrometer-sizes and accuracies), then it's worth a try. But then you need a mechanical setup in the same accuracies - submicron resolution and such ... I'm building a second setup beside my CNC-mill with 1/256-microstep-drivers, so i think to reach an accuracy in this range, buby VDX - General
Hi Lluc, ... best target for optimizing is the extruder ... Viktorby VDX - General
Hallo Daniel, typische 'gute' Motoren haben 200 Schritte pro Umdrehung und ziehen um die 2 Ampere Strom pro Phase bei 2-3 Volt Nominalspannung, du kannst dir einen RepStrap aber auch mit Motoren Aufbauen, die 'nur' knapp 1 Ampere bei 5 Volt ziehen, oder auch 0,4A bei 12 Volt, u.s.w. Schau dich bei um, ab Flanschgrby VDX - Altes Forum
... maybe Ian with 'BitsfromBytes' can serve as european link? Viktorby VDX - Mechanics
Hi Kerstin, as now it's a bit chaotic in structure, organisation and such, but maybe this is a chance too? When a project is developed to mature, it tends to 'freeze' in an optimized stage and new ideas have to fight their way through until the're common. I think we actually are in a decreasing 'brainstorming' phase, where different concepts, solutions and options are tested for usability - loby VDX - General
Hi Ru, i already mentioned using elastic magnetic stripes made from NdFeB-powder embedded in resin (see 3-rd post). But for orienting the magnetized particles in the hardening resin you need much more magnetic field than usual, as you have to overcome the high forces between the already magnetized particles to rotate them in the right direction ... Viktorby VDX - General
Hi Gene Hacker, i followed the f@h-development the last year too, but either f@h nor reprap can do the finishing - the surface-accuracy is much to coarse The best try in the actual stage would be lost-cast-moulding with fields metall or lowtemp-wax (which didn't stick to epoxy) and mould with epoxy ... Viktorby VDX - General
... here: you can download a free finite-elements-simulator for magnetic fields (for Windows). Viktorby VDX - General
... and here some nice chess-pieces, where the fabbing would be a little more complex : It's a rendered sample-scene from Povray - next i'll search a converter from POV to STL (or anoter common format) and retour and try with some other geometries and designing too ... Viktorby VDX - General
Hi Andy, ... i tried sometimes to make a paste with laser-toner from Sharp - either the toner didn't mix with the solvent, or when, then some of the ingredients thend to stick together, so the paste won't go through the needle AFAIK the toner consists mainly of latex and graphite with some additives. So you have to mix with the graphite, but shouldn't solve the latex ... Viktorby VDX - Mechanics
Hi Alex, the mirrors shouldn't focus the sunlight to much, they should better distribute the light between the tubes, otherwise the tubes would shadow each other. Tubes because of the same reason - in a big tank only the outer algaes receive the full sunlight - with tubes you have better distributing ... For the funghi: - besides of energy you need fabbing material too, so maybe it's easier anby VDX - Plastic Extruder Working Group
... there were some recent ideas to enhance the productivity of algae-growing with many communicating water+algae-filled glass-tubes surrounded by focussing solar-mirrors (similar to focussing heat for hot-water-devices) or UV-emitting lamps. For optimal results you have to arange two separate areas - one exposed to the light, another fully darkened, as most algae needs day-night-cycles ... Mayby VDX - Plastic Extruder Working Group