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Re: Arduino as simplified comm/controller board - 14 years ago

Hi Zach, ... it's the same for me, with the conversion from cartesian coordinates to tripod- moving. When my electronic works, i have to focus on the conversion, so your library could help me a lot ... Viktor

by VDX - Controllers

Re: Reprapping Engines - 14 years ago

Hi Ian, ... excuse me, i didn't want to offend you - english isn't so easy for me, so maybe i was a bit of ignorant? What pushed the thread-size was your declining of my setups as 'engines' and my explaining, that it's one indeed and that's good for 'powering' of pneumatic- and hydromechanics or 'artificial muscles'. So it was for me a legal 'engine'-definition - i think when i can perform mov

by VDX - General

Re: Reprapping Engines - 14 years ago

Hi Ian, ... if every 'ferrofluid-tooth' can withstand 0,3 bar, then with a sequence of 10 'ff-teeth' in a row i can pump 3 bar difference! If i need 10 bar pressure, then my pump must have 31 free 'teeth-cavities' and 30 'blocking-teeth' (also nearly 60 tooth-magnets in the wheel) for defining the pressure-difference in the radial pump, what's a bit scary ... For this reason i evaluated the He

by VDX - General

Re: Beware this variation on the Spanish Prisoner con... - 14 years ago

Hi Forrest, ... dropped in my Private Messages too ... Viktor

by VDX - General

Re: Hi german reprappers, where are you? - 14 years ago

Hi Sebastien, ... wait, until some more members comes together, actually it's not essentiell, germany isn't such a big country Viktor

by VDX - Schwarzes Brett

Re: Introduction: Hello, I - 14 years ago

Hi Matt, ... maybe in your next essay you should write a SF-story about sending an 'omni-reprap' to the stars instead of embryos I think, in some future there should be 'seeds' or probes sent to other planets in our or foreign solar-systems, where the probe starts with reprapping a fabbing plant, which builds exploration-scouts and other sophisticated stuff to scan the areal and maybe start a

by VDX - General

Re: Easy to build linear stages - 14 years ago

Hi Demented, ... i'll post the next steps of progress in the builders blog - when the software/drivers will work, then some videos too ... Viktor

by VDX - Mechanics

Re: Hi german reprappers, where are you? - 14 years ago

Hi Alex, ... you're welcome! How is your status? Are you on the straight reprap or on a repstrap? Until an europe-localized shop is working, the ordering from USA is a bit to troubling for me, so i'm actually on repstrapping .. With my experiments in solved powders instead of FDM it's another branch, but i think with a wider (practically unlimited) variety of materials an shore-values we coul

by VDX - Schwarzes Brett

Re: Turkey Roaster RepRap, almost tempting - 14 years ago

... i think, for supporting FDM-extruding, an intermediate temperature of 50

by VDX - General

Re: Reprapping Engines - 14 years ago

... the ferrofluid-pump works from low- to high-pressure as good as in the opposite - the red arrows didn't show the active pressure, but the flowing direction, when i turn the weel. The magnets are surrounded with so much ferrofluid, that it fills the gap between the magnets, and the stator-walls completely and acts as sealing. Between the magnets are cavities, which wanders with turning the w

by VDX - General

Re: Parallel-kinematics versus string-pod - 14 years ago

Hi Zach, ... access would be fine, then i can post some images and videos of progress and some experiments in the blog Viktor

by VDX - Mechanics

Re: Easy to build linear stages - 14 years ago

... i'm nearly ready with the mechanics of my vertically aligned Tripod: (from here: ) Viktor

by VDX - Mechanics

Re: Parallel-kinematics versus string-pod - 14 years ago

... here is an image of my vertically aligned Tripod-repstrap-demonstrator - i only have to mill the fittings for the ball-magnets, so next week the mechanic is ready, and i can search my driver-boards ... The height is 21 cm, footprint nearly 17x17cm and the working area is a cylinder of 6cm diameter and nearly 8 cm height with an estimated accuracy of 10 microns or better (not in every zone th

by VDX - Mechanics

Re: Live CD - 14 years ago

Hi Zach, ... look at LinuxCNC or EMC2 ( ) - it's for free ... They have Ubuntu as Live-basis, some CNC-programs and tools for controlling different setups and you can install the whole on your harddrive, if it's ok ... Viktor

by VDX - RepRap Host

Hi german reprappers, where are you? - 14 years ago

Hi all, ... i'm located in Grosskrotzenburg, near Frankfut/M, Germany. Wo's reprapping nearby too? Viktor

by VDX - Schwarzes Brett

Re: Reprapping Engines - 14 years ago

Hi Ian, ... the spinner is a pump, you need a motor to activate it ... Here is a sketch of the previous mentioned MRF-Engine: If you activate the solenoids in the sequence 1,2,3,4,1,2,3... then the MRF (brown) in the elastic hose (yellow) would travel slow from right to left ... Viktor

by VDX - General

Re: Reprapping Engines - 14 years ago

... here i have a sketch of a spinning magnet-ferrofluid air-pump ... Viktor

by VDX - General

Re: Reprapping Engines - 14 years ago

Hi Ian, ... i tested some MRF-pumping methods with moving and spinning magnets (see the image for two rotating setups), but for best pumping of MRF i had the sequencial switching solenoids - it seems, that the traveling effect in the elastic hose needs sharper activating and releasing edges, than the moving magnets can perform ... The spinning magnets works good with ferrofluid - when you close

by VDX - General

Re: Building Low Pressure Solenoid Valves - 14 years ago

Hi Sean, ... the magnets arent so expensive (maybe 10 cents or so) so that's not the problem - with my oszillating-pressure-setup there would be the real chance, that the ball drifts away from the holes, so the magnets on both sides are essential for switching the solenoids off after changing position ... Viktor

by VDX - Mechanics

Re: Reprapping Engines - 14 years ago

Hi Sean, ... there are many possibilities and methods, for working with potential-differences, when you can switch and direct forces to the right 'muscles' ... My simplest approach is an oszillating piston, which changes the pressure in the main-tube periodically between max and min (~vacuum?). Through phase-right switching valves i can selectively output pressure (valve open short before and

by VDX - General

Re: New plastic is strong as steel, transparent - 14 years ago

... actually most nano-work is spin-coating, film-drying or even dipping, as in this article ... Some months ago i found some clever guys aligning nanowires through solving them in soap-liquid, blow soap-bubbles and wet with one side of the bubble a silizium-plate, so the solved nanowires in the liquid-film could be separated, aligned and transferred to the surface of a SI-sensor For 'real' n

by VDX - Polymer Working Group

Re: Reprapping Engines - 14 years ago

Hi Ian, ... ok, boiling water can be used too Another point - i can build a pure current/magnetic-driven MRF-engine without heating and steaming, when i dont need much displacement. I described it already in another thread, but here is a short scetch: When i surround a MRF-filled elastic silicone-hose with three or more solenoids and switch the solenoids in a sequence, then the MRF acts as b

by VDX - General

Re: New plastic is strong as steel, transparent - 14 years ago

... it's mostly a composite from very hard and strong nano-particles (or ceramic-flakes) embedded in a polymer ... It's nearly the same principle, as in glass-filled epoxy-sheets (GFK) or 'virtual stone', where you fill an epoxy with sand - only the particles are much smaller and have a rough surface or some molecular structures on the surface, where the polymer-molecules can dock, so the struct

by VDX - Polymer Working Group

Re: Reprapping Engines - 14 years ago

Hi Ian, ... obviously right I'm maybe half'n step ahead - when there's an reprapped 'engine', then there can be reprapped 'muscles' too ... Back to reprapping 'hardcore engines'. With MRF-hose-valves and reprapped bellows- or membrane-chambers i have all together, what makes a low-temp stirling-motor. I need a low-temp boiling fluid in the chamber (maybe aether - but what's with dissolving

by VDX - General

Re: Reprapping Engines - 14 years ago

Hi Ian, ... what i describe, is a hydraulic machine, powered by a moving magnetic 'virtual piston', which articulates varying pressure, that is phase-senitive switched to the appropriate hydraulic 'muscles', and then bend or move the corresponding mechanical structures ... It's the same principle, as in an hydraulic motivated excavator, powered by a combustion-engine ... Or better a bionic-samp

by VDX - General

Re: Artifical Muscles - 14 years ago

... i found a new basis for my pastes: 'Lanolineum'or 'Cera Lanae' - it's pure wool-wax and smells strongly like sheeps, but it's soluble with water/glycerine or oil too and is only quarter the cost of dexpanthenol. For big amounts it would be much cheaper then dexpanthenol (e.g. 8 Euros per 100 gramm, instead of nearly 30 Euros!) and it seems to do the job as well as the other mixtures, so i'll

by VDX - General

Re: Reprapping Engines - 14 years ago

... i mustn't have heat or air-pressure to move pistons - as in the 'Artificial Muscles'-thread mentioned, i can build solid-state pumps and valves only from hoses and solenoids, if i have MRF or ferrofluid as active and transporting medium ... With MRF i already designed peristaltic pumps, which move the fluid only through serial switching of solenoids, without any moving parts ... With a diff

by VDX - General

Re: Artifical Muscles - 14 years ago

Hi Samuel, ... this is a mixture from carbonyl-iron-spheres (grade CC, that means nearly 50 microns diameter), vaseline and some vegetable-oil (from the kitchen) to reduce viscosity - no surfactant, because it's a MRF, not a ferrofluid ... It stays stable over months (i have some fluid mixtures which are 5 years old and working), when i have to much oil and/or there would be sedimentation, i ca

by VDX - General

Re: Artifical Muscles - 14 years ago

... here's my first experience with uploading a video to youtube: As you can see, i pour some MRF (Magneto-Rheological-Fluid) in the field of a neodymium-magnet, where it stiffens. With removing the magnets it went fluid again, and with applying the magnets it got stiff again, and so on, and so on ... Viktor

by VDX - General

Re: Furfuryl Alcohol and blocked catalyzers (formerly delivery woes...) - 14 years ago

Hi Fernando, ... sounds really good! Actually i'm bound with other tasks, but that's a way, i want to go - keep us informed and be carefull, not to rocket your house in the sky To the diode-lasers: you should salvage lasers only from newer Drives, so 40x or faster - in older drives the diodes haven't enough power, in pointers it's the same - with a 5mW-Diode there isn't a sensable heat in the

by VDX - Paste Extrusion Working Group