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General discussions. For specific printers / electronics / fabrication methods / softwares, please see other sections.
Re: SD Card > PIC24 > Route PCB - 16 years ago
Tony, Great job! What software are you using to create your PCboard layouts? How do you like it; is it freeware or something commercial? Thanks, Larry Pfeffer ursine at gm4il d0t c0mby Larry_Pfeffer - General
Re: CMM (Coordinate-measuring machine) - 16 years ago
VDX Wrote: > I have some commercial ferrofluid from Ferrosound, > but it tends to separate in the field of a > NdFeB-magnet, so a friend mixed some special > mixtures, which are more stable in strong magnetic > fields - the prototypes are still working after 5 > years > > Viktor Viktor, Do you have any information on what that special mixture is that resists separatby Larry_Pfeffer - 3D Scanners, Book Scanners, and Optics
Re: CMM (Coordinate-measuring machine) - 16 years ago
bjathr Wrote: > are the set of sensors closest to the probe > necessary? > (or rather, do you know how much precision will be > lost if they are omitted?) Greeting all, It seems to me that: to the degree that you can neglect any contact torques (about the center of the probe tip), then you can reduce the 6 DOF (three contact forces, and three contact torques about the tip's centby Larry_Pfeffer - 3D Scanners, Book Scanners, and Optics
Re: 3D scanner - 16 years ago
Jared, Thanks much for those two links. It's heartening to see that 3D scanning can be done without breaking the bank. The patent status of the Caltech work sounds like it could become an issue. IANAL, but it seems to me that pure algorithms cannot be patented, so this can probably be worked around legally. Larry Pfeffer, Lexington, MA, USA ursine at gmail d0t c0mby Larry_Pfeffer - 3D Scanners, Book Scanners, and Optics
Re: Rhode Island/ New England user group - 16 years ago
Sebastien, Is the SETC still in operation? The most recent entries I see there are dated spring 2007, and many of the links are broken (404.) The center for bits and atoms still seems to be alive/well, but whether the SETC is is unclear to me. No answer on their phone either (though, it's not disconnected.) I emailed the contact listed on that page (edwardbaafi at gmail dot com) and I'll reby Larry_Pfeffer - Rhode Island / New England RUG
Re: Rhode Island/ New England user group - 16 years ago
Hello John, Thanks for chiming in. I'm hoping to foster some critial camm of reprapping in the very-greater-Boston area. I'm beginning to feel some CNC-envy; you have a CNC mill, as does Peter. My mill is manual. I've only done a couple projects with stepper motors, both times using Jeff Kerr's picStep modules to control them. Sounds like it's time for me to dive in a bit deeper. I'll beby Larry_Pfeffer - Rhode Island / New England RUG
Re: Rhode Island/ New England user group - 16 years ago
Bruce, Thanks for your offer. If we can work out the timing, I'd really like to come down and see your machine(s) in RI. The AS220 group also sounds interesting. I'm too busy right now (work and a vacation the week of July 4th), but I hope we can schedule something soon after I get back. At the moment, I don't have much in the way of projects to show. I've still coming up to speed on the tby Larry_Pfeffer - Rhode Island / New England RUG
Re: CMM (Coordinate-measuring machine) - 16 years ago
Greetings fifo, et al, I think the CMM idea has merit. Whether an optical approach is better than a contact/mechanical one is a lesser issue. Interestingly, the previous post hints at one key use of a CMM head for reprap -- improving on the accuracy of the current mechanism. Using a CMM head on a reprap to measure the shapes of reference objects (whose true shape is known ahead of time) couldby Larry_Pfeffer - 3D Scanners, Book Scanners, and Optics
Re: Reprapable linear drives ... - 16 years ago
Greetings all, I'm new to this forum, so please bear with me. This type of linear stepper motor is also known as a Sawyer motor, after the inventor. The patent citation is Sawyer, B., \Magnetic Positioning Device," U.S. Patent 3,376,578, April 1968. Online (w/the right plugin) at: Making such actuators doesn't need large numbers of magnets, just lots of little iron (or other magnetic meatby Larry_Pfeffer - General
Re: Rhode Island/ New England user group - 16 years ago
Hello, Bruce (et al), Thanks for your kind offer of help. Right now, I'm reading up on reprap's background info, and trying to decide what I want to work on. (A backlog of competing project ideas, and never enough time....) Some time when schedule permits, I would like to meet and (even better) see what you've got going. Questions: What is the AS220 in Providence, RI? At what stage is yourby Larry_Pfeffer - Rhode Island / New England RUG