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Re: Lasers - 15 years ago
... i built a sintering system with a pigtailed 8-Watt-diode-laser for 320Euros, which i drive with a self-made current-driver in 0,65Ampere-steps from 0,65 to 5,2Amps (e.g. 0,5Watts to <5Watts output-power for longer life) The glass-fibre has a core of 0,1mm - i assembled a two-lenses-optic-head too and have a min-spot of nearly 0,06 to 0,08mm. With this laser-head i sinter gold-paste on aby VDX - Laser Cutter Working Group
Re: Paperwork or sheet-cutting for 3D-molds ... - 15 years ago
Hi Steve, ... VVBG (Very-Very-Big-Grin ) It's obviously not so a good idea to unfold beveled or high resolution-parts with smoothed edges (but this can be optimized by switching the cutting-edges, flaps and interconnections too). When you plan to start with sheet-work, then try to construct with basic objects and smooth the edges after solidifying - with filing or such ... A good strategy foby VDX - Plastic Extruder Working Group
Re: Paperwork or sheet-cutting for 3D-molds ... - 15 years ago
Hi Steve, ... Pepakura reads Binary STL's, so it seems to ignore the ASCII-STL's ... Here all input-formats: Pepakura Designer File - *.PDO Hexa Great - *.6KT / *.6KS Wavefront - *.OBJ Autocad - *.DXF Metasequoia - *.MQO 3D Studio - *.3DS Lightwave - *.LWO STL Binary - *.STL Google Earth - *.KMZ / *.KML I use mostly the *.3DS or *.LWO-formats as direct output from my programs, but i have to coby VDX - Plastic Extruder Working Group
Re: Paperwork or sheet-cutting for 3D-molds ... - 15 years ago
Hi Demented, ... it's absolute free, what sheet-material you use - with printing on paper, glueing on a hard sheet and cutting the outlines with a saw you can have any rigidity you want ... In Pepakura i can separate the sides in every fashion and flip or delete the suports as ia want, so it's an easy to use 'unfolder' for all kinds of 3D-objects. For milling in aluminium or dibond (plastic-shby VDX - Plastic Extruder Working Group
Paperwork or sheet-cutting for 3D-molds ... - 15 years ago
Hi all, here i'll post my first 'training'-experiences with paperwork for molding ... - first construct the object in Lightwave: - then import and unfold in Pepakura-Designer : - a bit optimizing: - print'n'cut: - and glue it together: ... then insert all tubes and special parts like screws or threaded rods and fill with polymer, beton, wax or other solidifying stuff. I'll tryby VDX - Plastic Extruder Working Group
Home-brewed plastic made from milk ... - 15 years ago
Hi all, ... i got a book with some funny experiments made with home- and kitchen-stuff -- a bit like 'McGyver-style', my older son love it Here i found a description how make a strong plastic and glue from milk (casein) You have only to heat milk (not to boil!) and pour some vinegar into, so the casein separate from the whey. When filtered and dried the casein you can press it in a mold orby VDX - Polymer Working Group
Re: Easy home-position-calibration with a web-cam - 15 years ago
Hi Jay, ... here a simple sketch: The resolution is higher, when the turned optic is far away, but then the image is darker too. Best lighting is with super-bright white-LED's, as the normal cameras are more sensitive in the blue range - a possible hack is to break away the IR-filter mostly glued on top of the glass-window of the camera-chip. When the light is good (or you can rise the sensiby VDX - Controllers
Easy home-position-calibration with a web-cam - 15 years ago
Hi all, ... because i had some displacement of the dispenser-tip every time i changed the dispenser, i tried to define or reset the new home- or Null-position with a web-cam. Here the images of a 0,2mm- and a 0,9mm-dispenser-needle, viewed with a self-made micro-cam: With the camera embeded upside-down in the corner where the X- and Y-axes have the home-switches i can easily define a very exaby VDX - Controllers
Re: Printing solar panels and batteries - 15 years ago
... many years ago i read an arzcle about a guy, who took the electrolyte from normal batteries, wetted paper in it, dried the paper, stacked it with alternating copper- and zinc-sheets to a dry-battery and connected the right sheets ... AFAIK two of this batteries are used in the "German Museum" in Munich to 'ping-pong' a mechanical high-voltage-toy since twenty years! So low-current-batteriesby VDX - Let's design something! (I've got an idea ...)
Re: Alibre Design - 15 years ago
Hi Nighthawk, ... it's a plain ASCII-STL with very much triangles (=9448 total, =280 thin triangles, =136 small triangles, no holes) and a very small scaling: X=1,31 Y=1,31 Z=0,275 - this is interpreted as millimeters in most of my importers ... Try to save and import as Binary or reduce the triangle-count and/or the accuracy to reduce the data-amount. I tried to open your file (the cross of aby VDX - 3D Design tools
Re: A madman with a blowtorch (problem soldering wire) - 15 years ago
... what's with a (silver- or tin-coated) crimp-shell around the wire (maybe soldered after crimping too) and then soldering the shell into? Should work much better, then with the naked wire ... Viktorby VDX - Reprappers
Re: Arduino as simplified comm/controller board - 15 years ago
... i only can make real syncing with a controler when driving the CLOCK-signal synchrone to all motors. Look in the Bresenham-algorhythmus for 2D- or 3D-interpolating of linear moving - this works ideally for stepper-motors, when every 'step' in the line is outputted as CLOCK for the corresponding motor ... Viktorby VDX - Controllers
Re: Beads Instead of Teeth? - 15 years ago
... the atached images in this post show, how i move the tool-head of a laserploter with two stationary motors over steel-wires. In the two last types with this setup i used wounded steel-wires with 0,5mm diameter and had an overall accuracy of nearly 0,025mm in a drawing area of DIN-A3 or 45x30 mm ... With this method it's no problem to apply high forces and speed - but it's not so rigid, thaby VDX - General
Re: Printing working 3D Body Parts already being done. - 15 years ago
... that's the interesting point! It's actually no real problem to print living cells in 3D-shapes to form body-parts ... It's possible too, make embedded blood-capilaries, basic bone-structures and so on ... But if you want to insert the 'intelligence' we need in form of nerves and some complexer systems (hormon-sensors and -sources, liver-like biochemistry), then it's a long way, until you cby VDX - Tissue Engineering
Re: Alibre Design - 15 years ago
Hi Nighthawk, ... maybe it's only the difference between Binary- and ASCII-STL -- open your STL-file in a texteditor, maybe you can check which (if a) compression-format is used too? Or append your STL, then i can look, if there is something unfamiliar. I use different programs for STL-output or converting from other common 3D-formats into STL ... Viktorby VDX - 3D Design tools
Re: Beads Instead of Teeth? - 15 years ago
Hi Jay, ... a twisted cable isn't so dimensional accurate, that a negative shape would fit over the complete length ... In past i drived with thin steel-wires (0,3 to 0,7 mm diameter) self-developed pen- and laser-plotters. For a good friction i wound the wire 3 times around DELRIN/POM-rolls (with 20 respective 40mm diameter) which were driven by stepper-motors and stretched the wires at one eby VDX - General
Re: Better self-replicating through 'flexonics' - 15 years ago
... OK, triggered ... Viktorby VDX - General
Re: Beads rather than belts? - 15 years ago
Hi Demented, ... here a sketch: Viktorby VDX - Mechanics
Re: HDPE Additives for better production - 15 years ago
... good point for nopheads HDPE-warping-posts: Viktorby VDX - Plastic Extruder Working Group
Re: Printing Nylon - 15 years ago
... AFAIK the string made in the scool-experiment with the two liquids in a glass isn't the 'real' nylon end-product - it's not so strong and homogene as the known nylon-wire. I think you have to cure/harden the reaction-string with wetting in some third chemistry or remelt and stretch it 'on the fly' ... Then it's worth thinking: either you 'weave' 3D-objects with the hardened string (as in myby VDX - Plastic Extruder Working Group
Re: Beads rather than belts? - 15 years ago
Hi Demented, ... in an older post about the same problem (some months befor) i described one possible workaround: - mill two halfs from aluminium with 3 (or more if for self-manufacturing beaded strings) halfspheric cavities in the size and distance of the beads ... - draw over the complete length a centric v-grove for the string ... - drill in one half holes to the cavities for injection-moldiby VDX - Mechanics
Re: metal laminates fabrication - 15 years ago
Hi Bob, ... maybe you should first try with a claw-pole alternator - only one coil, two star-shaped metall-sheets with bended tips an a rotor with some neodymium-magnets atached. It's very simple to build and mostly used as light-generator in bicycles, cars and small wind-mills too ... Viktorby VDX - Plastic Extruder Working Group
Re: Servo motor VS Stepper motor - 15 years ago
Hi Andy, ... i'm in a sort of cooperation with ISEL ( 〈=en&oldlang=de ), a manufacturer of CNC-systems - they actually prefer the use of servos instead of steppers too And i have a big old 3D-CNC-stepper-system (something like this but much bigger, stronger and older) from this company too, which i actually rework for higher accuracy and for milling and 3D-fabbing with different tool-heaby VDX - Mechanics
Repstraps with string-driving ... - 15 years ago
Hi all, ... as discussed here: - it seems to be extremely easy to build parallel-kinematic 3D-robots with string-mechanics. Look especially at Alex Joni's Toy: -- and Koppi's Toy: What's here actually not included, would be the third axis - for this i thought about making an elevated platform, moved by strings too, but it would swing around, if not feeded properly ... So i had a much betteby VDX - Mechanics
Re: Servo motor VS Stepper motor - 15 years ago
... it's interesting to look at the development of the driving-methods of printheads. In my oldest printer (a Brother-HR1-typewheel-printer) the head is moved by a linear-stepper with only a home-switch at the left side. The next one (a NEC CP6 24-needles-printer) has a big and strong 1,8by VDX - Mechanics
Re: Better self-replicating through 'flexonics' - 15 years ago
... i emailed John Canny (the Prof. behind flexonics) if he have some more actual infos or is interested in participating ... 'Soft' mechanical systems in comparison to 'rigid' ones are more interesting when you go down in the micro- and nano-scale, as you can't reduce the sizes and accuracies of bearings and other mechanic and electromechanic elements under a specific limit - either the costs rby VDX - General
Re: Questions about the stepper motors - 15 years ago
... ah, got the point ... When it's possible to perform single steps, then you can measure the voltage of every output-pin (or the coil-polarity) per step and draw a stepping-matrix. So you can check whether the coil-driving works in the right mode or if two coils are bridged ... Viktorby VDX - Controllers
3D fabric - 15 years ago
Hi all, ... what's about string-fabbing-methodes like weaving, knitting or crochetting 3D-objects with strings and FDM- or glue-dots? As you can get thin and thick strings on big coils, it should be possible to design a weaving toolhead, which connect the string not only in a plain sheet, but in 3D and complex arrangements. With a bit optimizing with a glue-dispenser for fixing dots or integraby VDX - Plastic Extruder Working Group
Re: Better self-replicating through 'flexonics' - 15 years ago
Hi Sebastien, ... this is the main point in my interest in parallelkinematic systems and the discussions in the threads "Artificial Muscles" and other related too ... I already developed and built some flexure-structures for micro-grippers and nanopositioners with piezo-actuators and hydraulic or magnetic driving. With some other micro- and nano-mechanic setups i can drive and move makroscopicby VDX - General
Re: Questions about the stepper motors - 15 years ago
Hi Reece, ... best way for adjusting driving direction should be an inverter and an jumper for selecting 'normal' or 'inverted' direction ... And for your Z-motor: - look if the DIR-signal changes polarity in CW or CCW mode. If not, then trace the conections - if yes, then it's something wrong with the adressing of motor-coils ... Viktorby VDX - Controllers