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Discuss any sort of mechanical stuff here: positioning systems, gears, extruding methods, etc.
Re: newbie, but enthusiastic - 14 years ago
QuoteLowest Bid RepRapped components (if anyone can offer!) Not yet. It takes a long time to make a full set of parts, and people with rep(st)raps capable of making darwin structural components are much more keen on doing other things with their time and materials right now Currently, the best way to obtain structural parts is to have them laser cut from the plans on the website.by Ru - Reprappers
Re: Help: X axis skip/jumps - 14 years ago
Quote...caching the printed object in the reprap electronics, so that there is no need for reprap-pc communication But not actually fixing the source of the problem Comms errors coinciding with motion problems seems like a bit of a smoking gun to me. You'd be best off waiting for someone who actually knows a little more about electronics (or the host software) to take an interest, but I wouldnby Ru - Mechanics
Re: Instructable: Make potato plastic. - 14 years ago
Quoterelative of mine had a pressure cooker explode under normal use a long time ago (30+ years), there was a lot of damage and severe injury involved. I know someone who was involved in a car accident. There was a lot of damage and severe injury involved. etc etc. Sometimes, these things happen. That doesn't mean they're necessarily common. Personally, I find the concept of pressure cookers sby Ru - Plastic Extruder Working Group
Re: Support material candidates - 14 years ago
QuoteWhat's wrong with the various(?) water-soluble polymers? PVA looks interesting... relatively easy to get hold of, safe to work with, high enough melting point that ABS won't melt PVA it is extruded on to, etc etc. The cost isn't too much of a problem if it is reclaimed after each build. I'm pretty certain that the time it takes to set would be the killer here. As you have some handy, tryby Ru - Plastic Extruder Working Group
Re: Why RepRap is failing - 14 years ago
But seriously; I can remember early forays into things like meccano and lego technic and capsela... I doubt I was totally representetive of some 'average child', but I didn't have any major problems. Assemble the bits according to the nice diagrams, wire it up and boosh, away you go. There's no reason why the mechanical assembly of a cartesian bot should be any more complex, given the availabiliby Ru - General
Re: Why RepRap is failing - 14 years ago
QuoteShould the rest of us start looking for this mythical and rare bright 12 year-old for future testing purposes? In the spirit of the project, you should probably see about creating one of your own.by Ru - General
Re: Gen. 2 Stepper Driver single sided - 14 years ago
Quotethen etch the doublesided board yourself, as I said earlier, its not hard to do. But it does require additional hassle. So why bother? There are other, eminently sensible reasons for using double sided boards. But in the absense of any other restrictions, there's no reason not to go for the simplest approach possible. I'm just playing devil's advocate here... I'm quite happy with the boaby Ru - Controllers
Re: Gen. 2 Stepper Driver single sided - 14 years ago
Quote"Why must it be a single sided board" ? Because etching or milling double sided boards isn't a trivial matter? Its *fiddly*. Single sided stuff is easy and quick by comparison. And ordering bits from RRRF is fine but given as they're on the wrong side of the atlantic I for one pay a bit of a premium for postage, and things do take some time to actually get here. So if you need a board *rby Ru - Controllers
Re: Fabbing overhangs ... - 14 years ago
QuoteRu: sorry, I thought it had been mentioned before, but I really don't have the entire mailing list in my head. ;-) Yeah, hence my suggestion for a page I'm not getting at you personally, or any of the other people who have come in with ideas that have already been considered. It was a serious suggestion, not a poorly veiled insult, honest!by Ru - Paste Extrusion Working Group
Re: Fabbing overhangs ... - 14 years ago
Quoteit would be quite easy to hang a [email protected] head next to the RepRap head. Fill the fab head with sugar coating and build layer by layer, as usual. I'm wondering if we need a 'Frequently Offered Suggestions' page on the wiki. SUffice to say, support material is never easy easy as it initially seems. Finding a material that extruded filaments actually *stick* to is a non-trivial task. You coulby Ru - Paste Extrusion Working Group
Re: Fabbing overhangs ... - 14 years ago
QuoteNow, having a RepRap rigid enough to do some light SDM would also be very, very shiny If it requires five axis milling, I suspect we'll be getting it shortly after i get a pony (editted for terrible spelling )by Ru - Paste Extrusion Working Group
Re: Power Supply (for Arduino clone and other G2 electronics) - 14 years ago
QuoteAnyway, using a computer power supply wasn't my idea, I just thought it was the standard RepRap power source. Oh, it is. I just wondered why you'd want to attach a big powerlead to the arduino. Which you apparently don't want to do anyway. So my confusion is resolvedby Ru - Controllers
Re: Mod for Stepper motor driver Board - 14 years ago
QuoteLMD18245 The uses this h-bridge, so you could get a pre-fabbed solution to your problems. He sells kits, I believe, but the schematics and firmware for the controller IC are open source. He also suggests that if you want big (5A+) motors, you should buy yourself a geckodrive to control them I'm just trying to dig up some of my old searches and sites on the subject of motor controllers..by Ru - Controllers
Re: Mod for Stepper motor driver Board - 14 years ago
QuoteI'm building a star tracker using two stepper boards and motors, my telescopes a lot heavier then my mill! Ahh, suddenly this all makes a little more sense I always assumed that star trackers would use a lot of gearing and some modestly sized, fast DC motors. Or even a lot of gearing and some steppers. Most scopes I've ever had the chance to play with were very nicely balanced and requireby Ru - Controllers
Re: Power Supply (for Arduino clone and other G2 electronics) - 14 years ago
QuoteIf I added the power from the power supply (and thus if I used both power sources at once), could it fry something? Or would it make no difference? The arduino diecimila has a jumper to select USB or other power source. I power mine solely from USB though; the alternate supply is only really useful if you want the system to run whilst disconnected from a PC. Which isn't practical for a reprby Ru - Controllers
Re: Power Supply (for Arduino clone and other G2 electronics) - 14 years ago
QuoteI'm sure there's a simple explanation, and I just haven't found it yet. What is it? I think its a plan to allow the reprap to be powered from a 12v only source, like a car battery. There's nothing to stop you making use of existing 5v lines if you have them though.by Ru - Controllers
Re: New Diagnol Tie for Reduced part count and build time - 14 years ago
QuoteSo why not thinking about a central connector for something like (or) bicyclespokes That's quite a nice idea, but I suspect that getting a suitable hub would be the problem there. Unless you got a couple intended for normal bike wheels, and sawed them in half. And then all you have to do is to take some suitable 'rims'... it all seems to be getting a bit fiddly, no? But it has given me somby Ru - General
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
Hurrah. I'm glad someone managed to produce some hard facts. I'm pretty lousy at those partcular little details of my argumentsby Ru - Controllers
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
QuoteNop has made progress with quality, so I don't think this is a valid statement anymore Gears are tricky sorts of things; people jump through a lot of hoops to make high precision ones. I don't think you can guarantee a perfect even finish all the way around a fine gear using our production methods. And for every little imperfection, you're adding to the final positioning error and backlash.by Ru - Controllers
Re: Patent Infringement (Stratasys) - 14 years ago
Quoteit will be really hard to RP one for a competitive price But that could be applied to practically anything the reprap makes, surely? Aside from custom parts which cannot be obtained commercially, everything else can be made cheaper and faster using conventional production methods. 'Course, the printed version doesn't have huge wads of tax and middleman profit slapped upon it... Also, speakby Ru - General
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
Just to continue in my previous grumpy vein... you can handle lower quality gearboxes with some backlash by putting the encoder on the output shaft. But you couldn't then have another gearbox to increase the resolution of your encoder, because you'd be using the same standard of gears which would add the backlash on again. You could use a high resolution encoder like the RRRF one, but suddenly tby Ru - Controllers
Re: Honeycomb filling - 14 years ago
I've pondered infill strategies a little, and came to the conclusion that having long filaments that zig-zag across the part is a good thing because a) its nice and fast and simple because you're not having to do anything more complex than bresenham line drawing and b) we have a whole bunch of parts which use this method which hold together pretty well. I don't think strength (or lack thereof) iby Ru - Reprappers
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
QuoteWith more precise positioning, we can create more precise geartrains, which can have less backlash I'm going to be terribly pessimistic about this. I suspect if you want high quality gears, you're going to have to use milling/lathing to make them. I'm opento dissent on this one, but I think it would be very difficult to print very high quality gears. QuoteThis isn't necessarily true. Sinceby Ru - Controllers
Re: Printing flexible heaters ... - 14 years ago
There's also the fundamental impossibility of printing a heater using a head with the same heater. But it wouldn't stop you making heaters for a build volume though, which doesn't have to be kept at 100 degrees plus.by Ru - General
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
QuoteSure, but a stepper/stepper driver combo is usually more expensive than a cheap DC gearmotor/DC driver/encoder. But then the cheap homebrew servos simply aren't anywhere near as good in a huge range of roles, though they do happen to work very well as the power behind an extruder. Hence my caveat, "Except in this particular circumstance perhaps" Your choice of encoder might limit your moby Ru - Controllers
Re: Cartbot with rotary and linear axes - 14 years ago
Quoteyou may not need parallel supporting rails on the stages. So I apply the brakas, and turn the drive shaft 45 degrees to tilt the stage. I then release the brakes. What keeps the stage at 45 degrees?by Ru - Mechanics
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
I was thinking of the homebrew-servo vs stepper comparison. Except in this particular circumstance perhaps, I'd be inclined to take the stepper most times.by Ru - Controllers
Re: Combining Optop Endstops - 14 years ago
Quotebut if your just a couple of pins short of world domination... I think you should suggest that as a marketing strapline for the Sanguino. Its a splendid little phraseby Ru - Controllers
Re: Using the cheap 101-5433-EV Mountain Switch encoder - 14 years ago
Quotemaking the encoded DC motor perhaps more like a stepper (better, actually) What makes you say that it is better? Given that it is lower, lower res, etc etc.by Ru - Controllers
Re: buil a componet - 14 years ago
I'd worry about getting a normal darwin working first. Once you've got that going, making new versions of the reprap will be much easier. getting a darwin printing successfully is a big enough task for now!by Ru - Reprappers