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Support for the quite nice RAMPS Electronics. See also http://reprap.org/wiki/RAMPS.
Re: Another 3 Axis Position System for a RepStrap - 15 years ago
Hi Demented Chihuahua, ... the threaded brass-rods i bought in the tool-store, it's a normal M5-threading - i only lathed the rods for inserting small ball-bearings with 3mm inner hole. The 'velvet' was a synthetic velvet-like fabric, i used it only, because it was there In particular you can use every fabric - it forms with time the form-grip for the threading. You can define the friction aby VDX - General
Re: Another 3 Axis Position System for a RepStrap - 15 years ago
... some years ago i build a 3-axis cartesian basis for a ferrofluid-nanopositioner - this one was very small, flat and simple - maybe it's of some interest for another easy to realize repstrap ... The foot-print is 18x12 cm (20x20cm with the overlapping knobs and the Z-'tower') and the possible way of 40x25mm wasn't so exorbitant too but as you can see in the second image, the XY-gliders haveby VDX - General
Re: Another noncartesic, but very simple 2-axis-positioner ... - 15 years ago
... the parts of the micro-scara-robot are milled from duraluminium (AlMgSi...), so they are strong enough and merely light - drilled holes in the arms lighten them a bit more too ... For my test i would prefer a dibond-compound and maybe stacking several milled sheets in a LOM-waffle or so ... With aiming of a reprappable design there should be tried to build compounds of layered plastics andby VDX - General
Re: Another noncartesic, but very simple 2-axis-positioner ... - 15 years ago
Hi drvanthorp, ... here ( or -on the last side) you have a sample of a micro-scara-robot with a similar mechanic - here you have an accuracy in submicron-range. As you can read above, i wrote "With stiff arms ..." - the arms should be of a leightweight, but stable structure, maybe a honeycomb- or dibond-compound (for example made out of plastic-foam and aluminium-sheets). This kind of stiffby VDX - General
Re: Cartesian Platform Built From Old Flat-Bed Scanners? - 15 years ago
Hi drvanthorp, ... most cartesian plotters have rails, which are fixed only on one side, the other runs free on a roll, so the rail isn't stable enough to move the extruder without deformation ... I found on both sides feeded rails (wire-moving) in old XY-writers and used this principle on a laserplotter-design, what worked very well - if you want a sketch, i can draw it ... For a lightweight-by VDX - General
Another noncartesic, but very simple 2-axis-positioner ... - 15 years ago
Hi all, here i have some images of another noncartesic 2-axis-positioner (proof of concept only). Two motors turn arms (direct or over angular belts), which are closed to a kinematic structure, that can be used for dispensing or other tool-works too. With stiff arms and compressed slack-free bearings there should be enough stability to perform milling or drilling too! The working-area isn't rby VDX - General
Re: What's about a really BIG reprap for mega-sized objects ... - 15 years ago
Hi Forrest, ... in the first post i described how to build thick layers out of construction-foam ... The outputted 2-components-mixture expands 5 to 10-fold, so a tray of 2 mm thickness (as extruded from the pinhole on the tube) would expand to a finger-thick cylinder. A normal tube has a weight of merely 500 gramms and the end-volume of the foam may be 15 liters or more! In school-experimentby VDX - General
Re: What's about a really BIG reprap for mega-sized objects ... - 15 years ago
... for me the Mega-reprap-concept would be very interesting, because here i can show the supreme capabilities of my magnet-joint-hinges in a tripod, which normally is not meant to build bigger than some centimeters in size because of the structural weakness of normally milled solidstate-hinges ... So i will probaly try it on my own ... Viktorby VDX - General
Re: The problem with extrusion - 15 years ago
... we had to bring to work a CNC-system with a dispenser-head for automated glueing clutch-tubes in aluminium-rings. With a air/vacuum-dsispenser and the special heat-curing glue there was a lot of trouble with controlling the heating of the dispenser and the nozzle. In particular we had to deal with the room-temperature and humidity at the workplace, so in the end i inserted a 3-staged heatinby VDX - General
Re: Microstepping - 15 years ago
Hi jono, ... i'm going the way of simplify the driving by using ready microstep-drivers as for example the 1/16-step SMC11 from nanotec ( ~ costs 30 to 25 Euros) or my own 1/8-step-boards with an IMT901 drivers-IC for use with 200-steps-motors (which i have in big quantity and varying sices and powers in stock, so i can give away some too). This simplify the software to output only two signalsby VDX - Controllers
Re: Alternative power supplies and voltages - 15 years ago
Hi SOI, ... my PSU inserted in the laserplotter supported the interface-electronics (PIC16??-CPU), front-controls and IMT901-driver-boards, two steppers with 1Amps-per-phase (in chopper-mode) and a RF-CO2-laser with 5 to 6 Amps at continuous running. The temperature over some hours continuous working was not more then 40by VDX - Controllers
Re: Ideas for motorizing old micron-screws wanted ... - 15 years ago
Hi Sean, ... a longer belt-drive was my first thought too, but this isn't the optimum yet ... If i use the original micron-screws, then i have the higher accuracy with 1 millimeter per revolution, but only 25 millimeters maximum way for X and Y (Z has two rails, both a bit harder to turn, so i have to insert a complete new axis). When i remove the 25-mm-micron-screws and insert a linear-steppeby VDX - General
Ideas for motorizing old micron-screws wanted ... - 15 years ago
Hi all, ... how can i best motorize the micron-screws in an oldstyle measure-microscope? Two images are applied - the screws goes in and out, when turned, so i have to deal with this too ... My first idea was to fix belt-gears at the outer ends of the screw-heads and simply drive them with a tooth-belt and a stepper-motor, so the belt can swoop over the disposition, but maybe someone has a beby VDX - General
Re: Alternative power supplies and voltages - 15 years ago
... here i have some images of my '20-years-old-but-still-working-prototype' 2-28V/12Amp-powersupply and the second-generation-pcb for 8xLM317T. With more LM's parallel i can add the currents - i think with a good heatsink there's {N}x1,3Amps without limit - as much N's, as you insert LM317T and shunts ... The other images are from my 2xIMT901-finestep-motordrivers and from an MC3479P-prototypeby VDX - Controllers
What's about a really BIG reprap for mega-sized objects ... - 15 years ago
Hi folks, ... what's about building a very big reprap (maybe 2 x 2 x 2 meters) with wood- or better bamboo-sticks for dispensing some centimeter thick trays of construction-foam? This would be a real eye-catcher at fairs or presentations and this sort of reprap could build really big (but coarse) objects, as for example scanned 3D-data from visitors, really usable furniture or other mega-sizedby VDX - General
Re: Alternative power supplies and voltages - 15 years ago
... i build a power-supply with 8 parallel LM317T and shunt-resistors for balancing the differences (as in an old project from a electronic magazine). With this i drived a laser-plotter with two 2Amps-per-phase-steppers an the supply of a RF-CO2-laser. The power-supply is regulated and can output from 2 to 28 Volts at currents until 10 Amps (max 1,5 Amps per LM317T, so 12 Amps would be the abs.by VDX - Controllers
Re: Arduino as simplified comm/controller board - 15 years ago
Hi Andy, ... you are right - for real 3D-printing you need a second extruder with support-material for overlapping and nonplanar geometries ... But there are other ideas, beside of extruding plastics, for building 3D-objects, so there sould be forks not only in the use of electronics, but in every aspect too. I throw in the discussion noncartesic mechanics with a very simple assembly, dotprintby VDX - Controllers
Re: wooden reprap parts - 15 years ago
Hi nophead, ... pigtailed means, that a fiber comes out of the laser-housing. A laser-diode is mostly a bar of active material (sometimes many aligned bars) with a very poor optical output-quality - the laser-diode emits a conical 'plane' of light, instead of a sharp laser-beam, as in a gas- or solid-lasers with the much longer and better resonators. With a special cylindrical lens there is aby VDX - Laser Cutter Working Group
Re: wooden reprap parts - 15 years ago
Hi Zach, today i've got a 1,1W-pigtail-diode-laser (see image) with a 50 micron-focus-tube for testing and playing around and i made first tests with gold- and glass-pastes (solved with dexpanthenol) and some burning/cutting ... First infos: the gold-paste (as mayby every other metall too) would dry very fast, but didn't sinter or melt to a solid because of heat-dissipating in the mass ... Theby VDX - Laser Cutter Working Group
Re: wooden reprap parts - 15 years ago
Hi nik, ... sounds very good for testing with the design - what's the price for all needed parts? On the other side, if it should be a straightforward reprap, then it should be able to do this work too! Maybe with a LOM-(Laminated-Object-Modelling)-building approach, where i stack sheets of self-adhesive (or glued together) paper or other material, and with a 'high-power'-cutting-laserdiode fby VDX - Laser Cutter Working Group
Re: Powder support - 15 years ago
... acetone is very low viscose and is drying very quickly, so plastics solved in acetone could go (maybe with an extra drying idle time per slice). Maybe sand as body-powder and ABS-acetone-solvent would be a good try ... Another idea: maybe it's possible to 'print' droplets with a dispenser instead of an ink-jet-head, when the dispensed fluid is outputted above the powder-surface in discreteby VDX - Mechanics
Re: Dot printing rather than Extruding? - 15 years ago
... for ink-jet-printing you need viscosities equal or lower then water! There are very expensive hot-wax-ink-jets, which print 3D, but the actual powder-3D-printers use normal ink-jet-heads with a glue-liquid, which is thinner then water for koagulating the powder. I think the 'objet'-printers use a very low-viscose epoxyde wit UV-curing to hardening the wet droplets on the surface ... Old thby VDX - Reprappers
Re: stepper motor bulk purchase - 15 years ago
... testing the needed torque of the motors can be easy made with a string wound around the axis (or a bigger roll on it for easier calculating), straightened horizontally and feed over a fixed roll and then append a weight on the string (maybe a small bag or cup for stepwise increase mass with heavy parts). So the motor can turn freely around and you can calculate the torque from radius of theby VDX - Mechanics
Re: Arduino as simplified comm/controller board - 15 years ago
... what's the trouble with direct driving all motors from one controller without hanging on syncing different driver-boards? When i first build a pen-plotter with steppers, i used a 6502-EMUF (german short for Single-micro-processor-board with universal-fixed-programming ) and a lot of discrete transistors, so the main advantage was to have many I/O-pins ... The next run was then with a PIC-cby VDX - Controllers
Re: Gluestick-gun as extruder ... - 15 years ago
Hi nophead, ... i disassembled the head a bit more (see the image) - there aren't wire-windings, as i meant, but two aluminium-blades separated by a kind of metallic-ceramic-blade as heater I think, the hint with the gluestick-gun is aimed to experiments with higher extruding-speeds (for example a lathe-style extruding on a roll or so). The small 7-mm-guns have much lower power, so this typeby VDX - Mechanics
Re: Gluestick-gun as extruder ... - 15 years ago
... OK, i read the comments ... Is some particularly wrong with them? In the local tool-store i have seen 5 or 6 different vendors with varying techspecs (and prices). My disassembled Glue-gun is from PowerTec, has 78 Watts and i used to disassemble it because of the weak housing and transport ... An "esco powertronic" with 500/40 Watts (heatup and constant?) and a much better transport runsby VDX - Mechanics
Gluestick-gun as extruder ... - 15 years ago
... i don't know, if someone already tried to use a gluestick-gun for melting plastic. In the appended picture there is a extracted heater of a gluestick-gun, which runs with 240V AC. With adapting of the inlet to 3- or 4-mm-sticks (my thicker Gluesticks have 11mm, the thinner ones 7mm diameter) and changeable nozzles (more expensive Pattex-guns have changeable heads, but others sometimes too .by VDX - Mechanics
Re: Parallel-kinematics versus string-pod - 15 years ago
... it's not so hard to make ONE straight edge - in all motors runs parallel, so for example say motor M1 and M2 are the both aligned motors in the back and motor M3 is the longer one in front ... Then it should run in a similar mode: X = M1 = M2 = M3 - if all tree motors run synchrone, X is straight X ... Y = (M2 - M3)xAlpha1 + M3xBeta1, where Alpha and Beta are trigonometric calculated valueby VDX - Mechanics
Re: nichrome alternatives - 15 years ago
... some soldering-tools have a tube-heater with a hole of 6 to 8 millimetres throug them. There are lowcost 12-volt-solders in use too, maybe it's worth to look, if the heating-heads are hollow, and then try them as extruder-heating? Viktorby VDX - Controllers
Re: New to Fab, resolution question - 15 years ago
... if someone has a thermo-transfer-printer or -FAX, then he already has an 3D-capable setup! In the thermotransfer-process a transfer-foil coated with a thin sheet of coloured thermoplastic is aligned with the paper and a moving printer-head with heatin resistor-pins melts the outputted pixels through the transfer-foil, so the melted thermoplastic can stick to the paper ... If i repeat this pby VDX - Tissue Engineering