... the mechanics define the maximum speed of the motors, so for some specifics you can drive faster with half- than with fillstep. My CNC-mill-controller is capable of 10kHz max. clocking speed - with fullstep an ramping i'll get max. 2kHz safe ... with half-stepping i'll get max. 6khz. So when calculating: - with fullstep at 2kHz and 25microns stepping over 200steps or 5mm per turn i'll receiby VDX - Controllers
... have a look at the forces when warping, mostly applying when the plastic is already solid and cools down - i don't think with electrostatics you will measure any usable effects ... it's simply not strong enough Viktorby VDX - General
... i learned that with microstepping i can get much higher clock-frequencies at smaller steps. With my 1/256-microstepping drivers and max 10kHz clock frequency i have an 'optimum' around 1/16 microstepping at 10kHz versus max. fequency below 2kHz at fullstep (depending of resonancy and mass-loads) or 6kHz at half-stepping with my Isel-drivers. Recently i've got four motors/drivers with 1/50-mby VDX - Mechanics
... we had a sticker with this text on the computerroom at Frankfurt university some thirty years ago Viktorby VDX - General
... schau mal bei Mädler ( ) oder Misumi ( ) rein ... Viktorby VDX - Altes Forum
annodomini2 Wrote: > For trials, little bottles of CO2 or CO2/Argon > used by small welders as a suggestion ... i have have all sorts of gasses on my daywork, but for realizing this at home too i'll need some more time - actually i'm building an exhausting-system for the laser, usable too for soldering and such, so my children (9 and 11 years old) can start with their own handicraft ... Vby VDX - Plastic Extruder Working Group
Hi Chris, ... i've got the laser for free - we're a small community across Germany where we can exchange help, spare parts and ideas for our different DIY-developments The lenses are common ZnSe-lenses - either as single focussing lens or as 'beam-widener'-telescope ... Viktorby VDX - Plastic Extruder Working Group
... for getting a feeling of the limits of the laser i made some tests and asked an application guy from the manufacturer - with a simple focus-lens i've got a spotsize around 30 microns ... with a 'beam-widener' and 1:5 enhancing the beam diameter befor the focus-lens i've got a spotsize between 10-15 microns (couldn't measure it better with my equipment at home) ... and with optimal adjustmentby VDX - Plastic Extruder Working Group
... a hint for making aluminium-constructions much more stiffer/sturdier: - build your frame with thin angles and sheets, insert some crossing threaded rods or long screws for fixing the outer dimensions and then fill the hollow frame with a sand-epoxy mixture (e.g. 32%-34% coarse sand, 60% fine sand and 8%-6% 2K-epoxy). So you'll get a solid frame with better mechanical properties than concreteby VDX - CNC Routers, Mills, and Hybrid RepRapping
Hi Marcus, in the X-axis, where the wire forms an endless loop, i inserted a wire-tensioner ... and in the y-axis both ends are simply fixed with screws to the left-side columns ... What's not visibele in the images: - i wound the wires several times around the motorized spools, so with tension the friction was enough to avoid slippage ... Viktorby VDX - Reprappers
... recently i've got a 50Watt Ytterbium-fibre-laser which is capable of cutting thin steelplates or melting metal-powder (or other materials too). My plans are to place the optic head along my CNC-millhead, so i have a defined reference-position of the laser spot when homing the machine. First i'm working on cutting and engraving, but the next step is a feeding support for powder, so i can tesby VDX - Plastic Extruder Working Group
Hi Marcus, ... in the images of my linked previous post, especially the image "X-axis.jpg", i used nearly the same geometry (only rotated 90 deg) for the X-axis of a laser-plotter. With the first prototype and 0.3mm thick steelwires i had some elasticity resulting in oscillation along diagonal paths (visible in the cutting trace) with an amplitude of nearly 0.2mm at a step-resolution of 0.04mm.by VDX - Reprappers
Hi Marcus, ... in past i built a laserplotter with steel-wires for moving the axes (look here: ) - you need high tension for the wires, so normal plastic isn't suitable for motor-spools and feeding rolls. I used lathed aluminium-spools and nylon-coated bearings where i lathed a V-groove in the nylon for the wire. Solid Nylon, POM or similar plastics can be used, but the reprapped body isn't sby VDX - Reprappers
Hi Armando, maybe you can simply soak the wood-surface with a solvent of waterglass and water, so it's coated with silicate - this is mostly used to protect wood (or paper) against fire ... Viktorby VDX - Plastic Extruder Working Group
... so maybe another way out there: build a reprap/repstrap, print optimized/better parts for a new Mendel ... and simply give away your 'old but working' reprap/repstrap Sid here from Germany is playing around with the idea to build a small bootstrap-reprap for shipping around as 'starter-set' for building daughters and then ship again to another person ... Viktorby VDX - General
... this was tried and made, you have to search the last year for something like "spacecraft", "toy" or something similar. I can't remember who posted the pictures, but he made a support-structure of easy removable strings with the same material ... maybe with playing around with the infill-parameter ... Viktorby VDX - General
Hi Beni, ... the "1.6Deg/Step" should be 1.8 and the motor could be a bit underpowerded - i have some old Nema23-steppers with 3V/1A until 1.1V/3A, what will fit for this kind of mechanic, but yours could do the job too, if you reduce friction ... Viktorby VDX - Mechanics
... i remember a tricky/funny way of outputting high complex binary patterns for CNC-machines without any CPU - simply attach a binary counter/latch to an EPROM where the dir-/step- or coil-activation-patterns are stored in ascending order. This could be simple accelerating data or even complex paths ... depending of the memeory-size ... Viktorby VDX - RepRap Host
... or try with moulding - so you can have any structural stability of your moulding material and the geometry of the printed part ...by VDX - Reprappers
Hi grael, in old-style CNC-controllers most ramping and accel/deccel was made with speed profiles drawn from a table with sinus-values - so you mustn't calculate on the fly, but it consumes memory ... Viktorby VDX - RepRap Host
Hi Enrique, ... i see you've added an endmill and laser too What are your plans about adding hatch-lines for the outer area for dismanteling the objects out of the bulk after laminating? Viktorby VDX - Skeinforge
... it's a small knife rotating free in two ball-bearings in the middle of the holder. Atached is another type with similar behaviour ... Viktorby VDX - RepLab Working Group
... here are two images of a DIY vinyl-cutter head and the result - should be doable with the reprap too ... Viktorby VDX - RepLab Working Group
Hi Torsten, ... thank you for the infos! The problems with viscosity at very fine nozzles are the main reason why i'm working with fluids and pastes at room-temp instead of FDM For an even smaller/finer application i developed a sort of pico-dispenser capable of dispensing droplets in micron-size (or even in submicron-size ) - look here: at the atached image "Folie3.jpg". The array is madeby VDX - Mechanics
Hi energetic, ... look here, at the last page: When you grind the tubes short, you can dispense extreme viscous pastes too and the smallest ID is 0.172mm (0.0068 inch) - but then you're highly limited by viscosity too Viktorby VDX - Mechanics
Hi RusLan, ..."CNC-завод" is a funny translation for "computer/numeric-controlled milling machine" The last years i was milling and fabbing high precision parts for microassembly and sensorics with my different CNC-mills applying different toolheads. I have an old CNC-mill at home and got it running with different standard CAD/CAM programs. Actually i'm repstrapping with this system and a paby VDX - Russia RepRap User Group
Hi RusLan, the translations are sometimes really funny, but OK You can write in plain Russian, but my answers would be best in English ... I have a CNC-mill and some toolheads for paste-deispensing and low-energy laser-cutting (1Watt laser-power, enough for cutting good absorbing foils). When next weeks i'll get a 20Watt-laser, then the next toolhead would be a sintering device for melting pby VDX - Russia RepRap User Group
... look at the 3D-printers from Z-corp or the DIY-inkjet-3D-printers - here a roll pushes the powder from a reservoir over the building area and then the inkjet rints the next layer of glue. Something similar schould be possible with sand or another supporting powder, but then you have to cover the complete building area, instead of some virtual enclosing shells with a co-fabbed border ... Vikby VDX - General
... smaller inner diameters need more pressure, so you are limited by the stability of the fixings ... increasing force/pressure tends to damage the extruder! Viktorby VDX - General
... i was thinking another way: With lowcost high-power diodelasers (i already have an 1Watt type with fiber and 0.06mm spot and will receive soon a 20Watt-LD with fiber and optics too) you can build a powder-sintering device, where the toolhead can melt/sinter a prelayd powder-surface or even better - apply powder through a small tube and melt it to solid or leave it as support. So you can 'drby VDX - General