Here's some inspiration on building your own 3D printer: http://www.channels.com/episodes/show/13163222/Extreme-DIY-Homemade-3D-Printer?page=5 Good luck with that. -Rod McCrady ----- Original Message ----- From: "Dirk Bonné" <dirk.bonne@xxxxxxx> To: python@xxxxxxxxxxxxx Sent: Wednesday, May 4, 2011 1:09:27 AM Subject: [python] Re: crazy idea? I think my next step should be to draw the front piece of the python in openscad, together with the design of all the joints. And then find somebody with a mendel-reprap and beg him/her to print one of the more difficult joints. I know there is a "hackerspace" in Copenhagen (labitat.dk) and they have a mendel-reprap. I live in copenhagen no more, but could visit them once. Dirk On 02.05.2011 10:27, Jürgen Mages wrote: >> The printers are slow and the material is not solid, rather a mesh of >> small tubes. Imagine a glue-pistol you steer by hand. You cannot >> produce overlaps so far, so things won't be easy, i'm afraid! > > There has been some progress meanwhile: 3d printing nowadays allows > more freedom. > > See here: > > http://www.psfk.com/wp-content/uploads/2009/01/photos_photo1032.jpg > > So, obviously no problems with overlapping. > > Also the variety of printing material has improved a lot. > > Cheers, > Jürgen. > >> >> I came across a bamboo bike build for africa, with connected with >> sheetmetal >> joints. I think you could use something like "dyneema ropes" running >> diagonally >> across each field and reduce the torque and sheer stress greatly. In >> theory, the >> wires only take pulling forces while the beams get the pushing >> forces, much like >> moulton or pedersen designs. There was a danish company desiging a >> bike for puma >> stores with a rope beam between steering pivot and pedals which could >> also be >> used as a lock. >> If you can adjust the tension of the wires, you could create >> universal joints >> that are bolted together regardless of orientation. I'm not so sure >> about the >> stiffness of such a concept. But if you come up with a cage-like >> design with a >> driver inside of it, it could be working! Never stop tinkering! >> >> I have to look at this cad-tool as well. if we could agree on a free cad >> packages, that is available to all of us, i would set up a >> repository, so we can >> share design and otehr documents! >> Keep going! >> >> Greetings, >> DirkS >> >> >> "Dirk Bonné" <dirk.bonne@xxxxxxx> hat am 29. April 2011 um 14:35 >> geschrieben: >> >>> Attached is a drawing of such joint. It would connect 3 tubes at >>> 90degree angles. >>> >>> >>> On 29.04.2011 12:21, Dirk Bonné wrote: >>>> A week ago I came across the reprap project (reprap.org), which is an >>>> "open source" 3D printing machine. Such a printer can print pieces of >>>> plastic, supposedly in any form as long at it is limited in size. I'm >>>> very much tempted making such a machine for my self (as winter >>>> project). >>>> >>>> One idea I have is to build a bike (e.g. python) using the reprap. The >>>> goal would be to build a trellis-framed python, like my own bike >>>> (pythoon) and some others seen on the project page. I would still use >>>> regular steel tubing with small diameter (8-16mm), but the joints >>>> connecting those tubes would be printed plastic bits that are pressed >>>> inside of the tube. The construction process would look like this: >>>> 1 design all the joints connecting the tubes. >>>> 2 print them -> results in "inner lugs". >>>> 3 cut the metal tubes to the right length (tube cutter). >>>> 4 assemble the frame by pressing the plastic joints in the tubes. >>>> >>>> => at this point I would like that the bike is stiff enough to hold >>>> itself. >>>> >>>> The next phase would strengthen the bike by wrapping uni-directional >>>> carbon fiber around the joints (like using a tape roll wrapping it >>>> around forming a "outer lug": >>>> >>>> 5 paint the tubes with a primer before wrapping the CF around >>>> 6 cut the roll of unidirectional CF in long strands about 1cm width >>>> 7 use a brush dipping the CF with epoxy while wrapping it around the >>>> joints firmly connecting the tubes to the joints. >>>> >>>> What I hope the advantages would be: >>>> * sharing: possible to share the design between people - anybody >>>> with a >>>> 3d-printer could produce a bike. It would even be possible to make a >>>> program that given some parameters can produce a custom measurements. >>>> * easier/quicklier: the tubes are just cu wih a plain tube cutter >>>> tool. >>>> There is much less measuring and filing involved (making a trellis >>>> frame >>>> can really be horrible - especially when brazing where precision >>>> means all). >>>> * easier: no need for a jig. The joints would make the frame pre-stiff >>>> enough to easily adjust the frame as a whole using a measuring stick. >>>> * equipement: no welding/brazing equipement needed (ok, you need a 3d >>>> printer....). >>>> >>>> Other directions: the same process would be useful for a pure >>>> CF-bike or >>>> may be a bamboo-bike... >>>> >>>> What is your take on the idea? Is there ny around iwth experience with >>>> 3d printing product?. Could it work? Would there be a real advantage? >>>> >>>> DirkB >>>> >>>> PS: with the reprap I discovered there is a 3D CAD for programmers: >>>> OpenSCAD. For those with the programming ability, it might be >>>> alternative for autocad and the like. >>>> ============================================================ >>>> >>>> This is the Python Mailinglist >>>> >>>> //www.freelists.org/list/python >>>> >>>> Listmaster: Jürgen Mages jmages@xxxxxx >>>> >>>> To unsubscribe send an empty mail to >>>> python-request@xxxxxxxxxxxxx >>>> with 'unsubscribe' in the subject field. >>>> >>>> ============================================================ >>>> >>>> >> >> http://dirk.steuwer.de > > ============================================================ > > This is the Python Mailinglist > > //www.freelists.org/list/python > > Listmaster: Jürgen Mages jmages@xxxxxx > > To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx > with 'unsubscribe' in the subject field. > > ============================================================ > > ============================================================ This is the Python Mailinglist //www.freelists.org/list/python Listmaster: Jürgen Mages jmages@xxxxxx To unsubscribe send an empty mail to python-request@xxxxxxxxxxxxx with 'unsubscribe' in the subject field. ============================================================