net3d Wrote: ------------------------------------------------------- > I found what looks like a very good motor at an > unbeatable price. Only four wires with 1.8 degree > step; but the motor is 2-phase bi-polar. Comparing > the model "SHINANO KENSHI #STP-58D4002-02" to what > is the closest model number available on the > Shinano website the motor _MAY_ have additional > sby Nathan - Mechanics
sid Wrote: ------------------------------------------------------- > I would think of an e-magnetic shutter instead. > Shouldn't be that much a controllerProblem (open > if extruderbarrel is turning, shut if not should > do I'd guess) > But I see a problem about cold material that keeps > the shutter from opening > > Maybe something like a needled nozzle, if the > neeby Nathan - General
> Bear in mind, though, that as of right now, > getting all the way to a working Repstrap is > likely to be extremely difficult or impossible if > you do not "have the time to properly figure out > how to use it all"... right now this remains a > research project, and successful Repstrap builds > require considerable time investment and a wide > range of skills on the partby Nathan - General
Hi Folks - isn't the idea that once we have a single reprap built then we'll be able to print the various plastic bits for the next one. Zaphod has printed the extruder bits from memory. Also - I like Joosts design but I've decided to use perspex for my bits and just use the blood sweat and tears approach. That's kinda fun and I'll learn a lot in the process. I also want to try extruding perspeby Nathan - General
Hi All, One of the most frustrating things about the extruder is the inability to completely shut off the flow of plastic at will - without drips. Are there any ideas out there on how this can be done? I keep returning to the idea of a powder bed melted by a fine laser to produce very fine melt patterns, rather than an actual extruder. Are there any ideas out there as to how our current extrudby Nathan - General
Just a request to the developers. Could you please ensure there is always a PDF file of the electronic circuit board copper traces available - I notice with the recent shift to manufactured boards there is no longer the PDF's. Same with the Opto switch boards (can't find the pdf at all). I don't mind printing an old board design as log as it works (you've linked to v 1.1 of the pwer and comms cby Nathan - General
I think we probably need to look at some sort of chemical process - use two part materials that form a higher temperature material when together. A dual syringe extruder should be enough. Self replication should be possible with smart design. (what would be amazing is to have one part as the regular material used so one one other material is required. But I don't know enough to say what would worby Nathan - General
There are limits to the ability of even an advanced Reprap to self replicate. In particular, if the melting point of one of the components (such as the heating element) is higher than the extrusion temperature then that part will not be able to be made. So we need to come up with a way of depositing high temperature materials at low temperature. It would be wonderful if this led to a way of deby Nathan - General
Well done! And if you don't mind - I'm going to copy it! That said - you will likely have an issue with friction due to the metal on metal design of the idler bracket in contact with the rod. So grease will be needed. Note also that the rod used could be replaced with tubes into which a hole could be drilled into which we could secure a screw-thus nullifying the need for trapped nuts. The tubeby Nathan - Darwin
From what I can see you didn't use trapped screws. Is that right?by Nathan - Reprappers
Any reason we can't use a 1.8degree per step motor rather than the baselined 0.9degree motor? Resolution is likely the issue but is it that bad?. Can mircostepping be accomplished using the pic program?by Nathan - General
Hi All, Those of you based in Australia may find this handy. I've been doing some searches on the net and have found some suppliers: Stepper Motors (& controllers!): - I'm going to buy a couple and try them out - they have a step angle of 1.8 degree and decent torque. also do them but they are quite expensive due to the higher quality (meant for industrial use). Drive Belts, bearings &amby Nathan - General
Instead of using a 3d cartesian robot for the printer is there any reason why a 'simple' robot arm couldn't be used. A robot arm could also easily change heads (or carry multiple heads). they would also be useful for CNC machines. Im assuming that there are 2 main reasons they haven't been used: 1: they were expensive and complex back when CNC machines were being developed so noone really thoughtby Nathan - General
The professionals have two tubs and a roller. One tub is filled with the powder and the other is the build surface. The powder tub's base is raised, which raises a layer of pwder above the rim of the tub. A roller then moves across and pushes the powder onto the build surface. The syringe then squirts a binder in the desired pattern. The build surface then drops a step, the powder tub raises a sby Nathan - General
The ball bearing would be made possible by the fine layering permitted by the inkjet head. You'd have a layer of powder, a fine layer of binder, let it dry (its probably a heated chamber) then the next layer of powder. The powder would have to be adequately removed but assuming that is possible then there is no reason why the bearing shouldn't work.by Nathan - General
sai Wrote: ------------------------------------------------------- > A PC power supply is one of the cheapest power > supplies you can get that has a reasonable power > output, so it's a good way to go. A 12V lab > supply is much more expensive, for example. > Although a car battery will work just fine too. > > The heater element consumes 2 to 3A, and all the > motors tby Nathan - General
What options are there other than pc power supply? 12v is easy to come by but do we really need 8 amp?by Nathan - General
Hi All, Looking to build a reprap type device down here in Australia but I'm finding that I can't make a decision on what type of stepper motor to use. What are the current reprap contributors using? I'm worried about spendin money and not having a powerful enough one. I'm thinking NEMA 17 but might be too powerful? I'm also kinda uncertain about using the threaded rods to move along the axis -by Nathan - General