Hi Forrest, when using soldering paste i have the same when the metal-base isn't hot enough. You have to heat the metal around, and then dip the braising rod into the hot-spot, so the melting front wet the surface and didn't form a blob on the rod itself. A hint for aluminium: - there are some aluminium soldering pastes around, which can be used with a normal soldering bit ... Viktorby VDX - Plastic Extruder Working Group
... here the promised images (some more detailed at the bottom) Two pneumatic paste-dispensers (the big one with a heater): Some tools for pick-n-place and micro-handling: Viktorby VDX - Paste Extrusion Working Group
... there's a lot of possibilities with embedding prefabbed parts and/or changing materials 'on the fly' while fabbing the body/housing. When at home again, i'll post some photos of tweezers and vacuum-grippers, i designed for microassembly - with milling i can make any shape or type of pick-n-place toolheads or specialized tweezer-inserts. As mentioned before the only actual problem i see is tby VDX - Paste Extrusion Working Group
Hi all, ... i had some ideas with embedding spacer-parts in the fabbing, so you could fab complex objects with overhangs without the 'teardrop-shape' in vertical bores and such ... It's the same idea as embedding sticks, rod, threads ant nuts in a mould, but here included in the fabbing process itself. When you want to build with the same material, then you can prefab the parts to embed in a pby VDX - Paste Extrusion Working Group
... i was thinking about optimizing a glue-gun for using ABS-filament ... Viktorby VDX - General
... nice tool-head for a repstrap Viktorby VDX - General
... continuous lines, criss-crossed over the slices, are much, much faster ... One good point for circles are the complex arrangement of circular and triangular tubes (where three circles connects) and you can forget the outline, when the circles are small enough. Viktorby VDX - Reprappers
Hi Forrest, ... replace the steel with other low-melting materials and you'll be on the way I'm on a similar route with my 'room-temp-paste-fabbing' and have some possibilities around for heating samples until 600by VDX - Casting and Moldmaking Working Group
... if the stepper hasn't to run very fast (e.g. <1kHz) and pulls only 0,7Amp per coil, then the single-chip-driver MC3479P is the simplest route - here some images of my first prototype (built around 1985): Viktorby VDX - Controllers
... my primary idea was to use this sort of heating-sheets in the bed and around the inner housing for temp-stability until 200by VDX - General
... reading the specs of Kapton-insulated flexible heaters ( ) i found that this kind of heaters should be printable or made with etching. Maybe a good thing for heating the bed/housing or as tube around the extruder? Viktorby VDX - General
... here: is an interesting paper about fabbing (with a f@h-printer) and sintering objects fromm steel-powder-slurry. It's very short, but touches some points we had discussions about - warping, shrinking, heated syringes, paste-extruding and such ... Viktorby VDX - Casting and Moldmaking Working Group
Hi Richard, look at the spread of 3D-CNC-milling over the last 20 years - there are expensive comercial machines (>>50000$) with high accuracies and throughput, but now even more home-made or 'cheap' CNC-kits are around, so 3D-milling or engraving is a 'standardized' common methode every interested individual with 1000 to 2000$ (or even less, i reworked an old CNC-robot for ~500$) can buyby VDX - General
Hi Matt, ... instead of cement you can use a mix with 6% to 10% epoxy with sand - it would better fill and grip and you can mostly adjust the settling-time by reducing the hardener-component from 30 minutes to some hours (or even days). Look here: Viktorby VDX - Reprappers
Hi Richard, ... some comments ... 1. - sure ... 2. - look at and - it's dort of open-source too. And there are some other individuals and groups scattered worldwide, which are on the theme too ... 3. - maybe, time will show ... 4. - this will change with the evolution of home-brewed RP ... You have many parts around, made from resin, which can be replaced or optimized. I'm on experimentby VDX - General
Hi Ru, ... look through the links in this post: ... especially the different kinematic-concepts here: [155.69.254.10] There are many different ways of enhancing the accuracy with parallel kinematics or special setups. My favorite is the bionic approach, where we print elastic morphing structures with embedded hydraulic structures - as discussed here: Viktorby VDX - General
Hi sid, ... same electronics, other software ... The main advantage of a BRR (read 'babyreprap') would be lesser friction and so smaller motors, shorter rods, belts, studdings ... and such. So it's something cheaper and more portable/shippable ... Viktorby VDX - General
... this lets me remember an old thread about fabbing objects out of uniform shapes - as lego does from bricks, here stacking small uniform spheres to a bigger object. So you haven't to remelt the balls, but simply heat a small zone on the base and pick-n-place the balls into the molten area. With smaller spheres (e.g. 1mm diameter or even smaller) you should have a finer granulity and with shoby VDX - Plastic Extruder Working Group
... not in my basement yet But here: (flyer: ) is a 'hand-injection-moulding-gun' with nearly 1000bar pressure. AFAIK the pricing is something to 2.800 Euros for the hand-gun excl. the press ... Viktorby VDX - Mechanics
Hi Larry, look here: and here: ... i milled 'oven'-soapstone (what's much harder than normal soapstone) and millable ceramics from Doceram ( ) with normal carbide-millheads. But millable ceramics are much more expensive, so i'll use soapstone instaead It's no problem to mill or to lathe soapstone or this ceramics, but you need carbide tools and best with coolant ... Viktorby VDX - Mechanics
... look here: in the post "Assembling the Tripod..." - here i constructed a 'babysized' parallelkineamtik bot as demonstrator for another project, but this 'toy' would fit the terms and is very easy in building and assembling - only the controlling software is a bit more tricky ... Viktorby VDX - General
... use a gear with needle-like tips or insert needles in a milled encoder-wheel with small radial v-grooves for inserting steel-needles - then the encoder wouldn't slip ... Viktorby VDX - General
... i have pieces of PTFE-coated glass-fabric with a glue-back, so it's simply used like normal self-adhesive - should be common in hardware-stores i think ... For bulk-PTFE-blocks/stripes i use screws only ... Viktorby VDX - Mechanics
Hi Sid, ... here in Germany i use mostly - - in it's original configuration or sometimes - - because of the better boolean syntax ... Viktorby VDX - General
Hi Steve, i was thinking of tank threads too, but it seems to be very complex - you need a special narrow shape fitting the filament, what's not common - so you have to build all the parts on your own. For synchronizing three screws you can build a ring with 6 gears: one is the motor, then every 2th is a screw and two dumb gears between for syncing and closing the transmission. Or imagine planeby VDX - Controllers
Hi Sid, falls du Greifer aufbauen willst, kann ich dir evtl. weiterhelfen helfen - fby VDX - Altes Forum
... atached is a photo with the fabbed parts of both prototypes - the creme-coloured is built from starch, the greenish one should be from gypsum powder with some green colour in the glue-ink ... The basic idea was a high-precise gas-pump with airtight and 'eternal' sealings. When some guys asked for a peristaltic blood-pump, which didn't smash the blood-cells, then i simply inserted two thin eby VDX - Plastic Extruder Working Group
... nope - the ferrofluid is the sealing medium settling along the linear and the spiraling magnet-rails. I designed the pump for transporting gasses or fluids which didn't mix with the ferrofluid or when inserting two separating membrane-tubes in the slit between spindle and tube for pumping blood Imagine fluid half-ropes along the magnetic rails, maybe 7mm wide and 4mm high. When i insert tby VDX - Plastic Extruder Working Group
Hi Sid, wenn du den Selbstbau-SMD-Bestby VDX - Altes Forum
... 'magnetic fabbing' is pure high-tec and high-power ... VAC in Germany builds crazy shaped magnetic objects with NdFeB-granules embedded in resin - AFAIK they use magnetic fields with 5 to 7 times more force then the finished objects should have! It's much easier to fab the non-magnetic body/housing and insert NdFeB-magnets. Here a sample of a magnetic-ferrofluidic pump where i inserted liby VDX - Plastic Extruder Working Group