I found myself silver-soldering the cable in the RepRap in FoAM.. killed all springiness in the wire. I abandoned the flexible drive shaft. If the filament has a low bend radius, the answer is simple; use a longer feed screw and mount the motor further away from the extruder barrel. The longer the screw is to the motor, the lower the curvature required of the filament. Direct drive lowers frictiby tobyborland - Reprappers
University of East London, SMARTlab, The machine shuttles between this lab and the arts building (the AVA). SMARTlab has some jolly toys if anyone needs milling or laser cutting work done.by tobyborland - United Kingdom RepRap User Group
Only one way to find out.. pity you can't get surface mount stuff in Duplo sizesby tobyborland - General
I presume the PTFE is to provide a form of thermal insulation from the support bracket. We have used "Gun Gum" as an alternative to JB weld out in the wilds of East London. It's an exhaust sealant mentioned in an earlier thread. As an exhaust sealant it is rated over 1000degC. Our next intention is to mount the heater barrel in a cylindrical mould and form a plug of Gun Gum on the end the same diby tobyborland - Mechanics
Add a few drops of glycerine to the RTV builders silicone if you wish to cast deep sections; I recommend mixing thoroughly. We used clear silicone with a trace of acrylic to see if it had bee mixed all the way through. The smell is acetic acid (vinegar). A wide diameter pulley with a thread on it will work with cable similar to a toothed belt and gear system. Similar to a draughtsmans table. Thisby tobyborland - Reprappers
Seems that one could mount a Dremel into the X-carriage of a Darwin machine with a V-point engraving tool and mill out a circuit board. We do this on a Modela MDX-20 here. It occurs to me that the Darwin frame has similar positional accuracy. A walk in the park for surface mount designs anyway.. Tby tobyborland - General
The parts here were used on the Science museum RepRap. We are now fiddling with an extruder to convert CAPA granules into CAPA filament. There is now a flickr page with some details of the finished parts. Part of the reasoning behind the ply version is that it is directly compatible with Darwin and one can swap out parts as they are made. The latest manifestation has ball bearing pillow blockby tobyborland - Mechanics
Umm.. Anyone in the London area can call into the lab and get the lasercutting free (go get yer own acrylic). Im in MAGICbox, SMARTlab, UEL, E16 2RD with a laser to play with in an open access lab. We have a plywood-based rep-rap too. Before you ask, I'm already posting rep-rap stuff abroad, so I'll get that out of the way before I offer that service. Cheers, Toby Borland (tobyATsmartlab.uk.com)by tobyborland - Mechanics
Oh dear.. Just looked at the CCTV article and it doesn't explain the open hardware concept at all. I don't think I managed to explain the difference between consumer 3D printers and the open hardware community. I think BBC did an interview for their website too, but I don't know if it goes into detail about the RepRap. I'll post some of the footage we got during the show and more importantly repoby tobyborland - General
Ahem.. The Museum of Science and Industry, Kensington, London, 20th Decby tobyborland - General
There will be a RepRap puttering away in the background of the Antenna Science Museum event from tomorrow till Sunday. Sorry about short notice, I've been trying to assemble it for the deadline. The parts are made from laser-cut assembled plywood and it runs smoothly I'll put the teardrop RepRap logo in the background and there should be someone on hand fiddling with it + expounding the joys/sorby tobyborland - General
RML-1 is the Roland plotting variant of HP-GL/2. I found that the Roland MDX-20 seems to accept HPGL reasonably gracefully. But its still controlling the Z-axis with Pen Up, Pen Down commands. The standard is not widely published and can sometimes turn up on FabLab sites. It may indeed be possible to use the RepRap software to drive a simple mill, but I think there are fewer demands placed on caby tobyborland - General
How about using two linked Peaucellier-Lipkin linkages on two corners of the Z-table and leadscrew on the other corners. Anyone pondered this? Way less friction methinks.by tobyborland - General
The files RRC_* place all the parts for the RepRap on to 2.5 sheets of A2 3.5mm ply. The 3.5 is important to obtain a good fit. The other two files contain the individual parts. Note that there are no PCB mounting brackets or opto-flags as I figured I'd be as well cutting them from aluminium sheet and bending them to shape. So how does it all go together? Hopefully I will be posting images of thby tobyborland - Mechanics
The capabilities of the machine are evolving, as are the capabilities of manufacturing. My thread response looks at the niche of a home 3D printer/fabricator within a wider socio-economic context. The potential of a machine which can drive its own refinement is also interesting; not to mention the interaction at the level of the forum. This is, in a sense, one of the first distributed hardware deby tobyborland - General
I attempted the plumber's solder approach first and finally resorted to brazing the joint. I don't know if the cable was S/S or galvanised but brazing worked as usual.. only that once I brazed the cable it lost some of its temper. There has to be a mechanical connector (maybe electrical terminal block with grub screws) that avoids this fandangle.by tobyborland - Mechanics
Hello all, I was grappling with the same problem (and flexible wire). If the feed screw is conically tapered then the motor axis can be inclined out of the way of the feed material, one trouble is that this screw must be machined. An easier prospect is to employ a wide diameter feed screw and recalculate the rpm/pitch parameters, this has the drawback of requiring yet higher gearing. Tobyby tobyborland - Mechanics
Hello folks, It would seem to me that the current manufacturing model is efficient in optimising production efficiency but is lacking in allocative efficiency. In other words, you can have any colour Ford model "T" you want so long as its black. I do not see 3D printers competing against the equipment required to produce plasma screens, nor do I see what is essentially a very unspecialised machiby tobyborland - General
Howdo folks, G-code describes toolpath motion. The great difference between 3D printers and CNC machine tools is that 3D printers fill a space whereas CNC tools carve it away. The fiddly thing about writing decent G-code generators is figuring out the order in which to cut away the material, this is lots easier for 3D printers which just have to fill a space. My 2 cents, the actual description oby tobyborland - General
With a self-replicating machine, there is the chicken + egg problem associated with devising the first machine. If there is a clear design path of evolution it should be possible to fabricate a machine which can generate ever more sophisticated versions of itself. A simple and rudimentary (read inaccurate) machine might have the capacity to produce the components for a more precise version. Thisby tobyborland - General
The parts were cut from 3.6 mm ply on an Epilog lasercutter in the MAGICbox lab (UEL), the parts fitted on to 2 & 1/2 sheets of A2 and took about 4.5 hours to cut (a not the most efficient file). My guess is that they would set you back about 400 quid at a commercial place. I'll post the DXF CAD files once I've successfully tested one. We may do a few sheets for free/barter in kind for seriouby tobyborland - Laser Cutter Working Group