> PCB: $40 I'd drop the PCB. Instead, use something like polulu's TB6612FNG Dual Motor Driver Carrier to drive the extruder heater. This can be parallelized to get 2Amp continuous/6Amp peak. All the extra components, capacitors, resistors, etc. should come in under US$5, and can be soldered without adding extra PCBs, and also, should be solderable onto the existing pins on component boarby BeagleFury - General
Hi Arvin, If you only attach at one point on the platform, the figure 8 seems overkill. A simple 'steel cable' belt drive seems simpler, and again, leads to the question, "how does the motor drive the cable?" I believe the reason for additional complexity in the figure 8 is that you add a mechanical negative feedback loop for any perpendicular torque acting on the platform... imagine on your cby BeagleFury - General
This idea seems nice, workable, and seems to be something easily aquired in most world locations. Any thoughts for the structural components necessary for pulleys, tensioning, clamps (to attach cable to movable platform), drive shaft attachment, etc? My initial thoughts would be: 1. Larger pulleys better smaller pulleys (less stressful on the cable) 2. Tension the cable using an L-Bracket, aby BeagleFury - General
sircastor Wrote: > > Everything has a beginning. Certainly, if you > > don't want to wait for one of the new > > developments, or until 3D printing is common > > place, trying to use an existing repstrap is > > certainly a good thing. Only thing being, it > > seems there is great frustration with the > options > > currently available. > > Theby BeagleFury - General
sircastor Wrote: > I think we should stick with already utilized > ideas within the community overall. I see the > appeal of the ball+chain drive, and I have to say > that I am intrigued by RepOlaRap. But in the case > of both, there is only one or a few people doing > it. I want to err on the side of "Lots of people > have done this." Everything has a beginning. Certainly,by BeagleFury - General
I don't want to overpromise, but the structural parts of RepolaRap XY platform so far have cost me about US$70: $5.09 neoprene .2" pitch timing belt 1/4" x 37". $6.99 neoprene .2" pitch timing belt 1/4" x 57". $14.80 2x acetal pulley, 10 tooth. $7.66 100 5mm alloy steel metric balls ~$8.00 5/8" 3'x4' mdf panel ~$5.00 1/8" 3'x4' hardboard panel ~$3.00 1x3"x24" popular lumber ~$6by BeagleFury - General
nophead Wrote: ------------------------------------------------------- > I am not following you BeagleFury. How do you hold > the middle of something down by tension at the > edges? As I stated earlier it needs infinite > tension to hold something flat. I guess it depends -- is there an epoxy, cement, or other adhesive compound that will attach the kapton film to aluminum? Pretty muby BeagleFury - Kartik M. Gada Humanitarian Innovation Prize
On the belt / tension, all that would be needed to keep a flat surface is to use strips of trapazoidal, non-flexible material to which you adhere the film, a long 'foot' to press down on both sides of the edges (the foot presses down to apply tension during printing, and releases to allow the belt to be advanced. Cross section as something like: ==================================== <- flexiby BeagleFury - Kartik M. Gada Humanitarian Innovation Prize
SebastienBailard Wrote: > Adrian and Ed have done a good job of doing up a > spreadsheet and I'm not going to attempt to push > any unnecessary work onto their plates by trying > to get them to release in another format. I agree on passive aggressive warnings; Are there features / tools to do on-the-fly conversions on the server side? Google often has the "view as html" for PDF docuby BeagleFury - General
Julie does have a point -- it would be better to have both the 'source' document, the ODS file, as well as one or two easy to read formats. I would suggest TEXT and HTML; both of which, I believe Open Office can save as. For a spreadsheet/table based document, the text would be tab or comma delimited; I would not use PDF, as that is not as open a format. What would really be nice (something tby BeagleFury - General
sheep Wrote: > At present this, like reprap > is still much a dream with an alpha release > pretending to be a stable beta. Open Office has as much stability, usability, and history, if not more so, than most integrated office productivity applications. What software do you normally use? I'd use open office over microsoft word any day (I lost count of the number of bugs I've hit editiby BeagleFury - General
Okay, have spent another good chunk of time on the firmware. Tried to get Triffid_Hunter's serial into the mix; unfortunately, it looks like it doesn't work on the Mega (port/io wrong, I'd guess). Rather than spend too much time getting it to work, I'm shifting back to the Arduino provided serial comms; my logic has reliable transfer, so losing bytes or having noise just slows things down, no gby BeagleFury - Firmware - experimental, borrowed, and future
aka47 Wrote: > It is better to be the 5v line rather than the 12v > line. Purely because 5v then needs no regulator > (Cheaper), and a 5v to 3.xv regulator runs a lot > cooler and is less wasteful. Except if most devices are 3v3, there would be no 5v line. Mixing voltages will be more complicated; maybe it would be simpler to scrap the whole "compatible" idea, and simply require aby BeagleFury - Controllers
aka47 Wrote: ------------------------------------------------------- > On 3.x volts. > > The BEEF back plane is passive so will be > comfortable being run at 3.xvolts if you wish on > the digital IO. All cards that will use the > signaling though need to be compatible. Cool. Since I suspect 3v logic and 5v logic will both be fairly common, I propose that all cards to be usedby BeagleFury - Controllers
Triffid_Hunter Wrote: ------------------------------------------------------- > quick heads up, adrian posted the latest gcode > reference up on the wiki, and it specifies > optional line numbers and checksums- so now we can > consider each gcode to be a packet since it can > now have a unique identifier and a checksum! Yep. It's great he's done this, though there still can exisby BeagleFury - Firmware - experimental, borrowed, and future
Lionel Wrote: ------------------------------------------------------- > About plastic toxicity, thermoplastics are not > toxic (as long as they are used well below their > ignition temperature, of course, and as long as > they are polymerised. Monomers are usually > toxic). Upon heating beyond a certain range, some thermo-plastics will decompose into dangerous chemical, the most cby BeagleFury - General
MarcusWolschon Wrote: > > Again, if the boolean operation was 'wrong' > more > > than likely, your model was inside out. > > THIS IS A KNOWN BUG. > I´m not the only one experiencing it and > there is no way you can reliably make a union > instead of an intersection,... with wrong > normals. > (And I guess the normals of 2 freshly created > cubes > are vby BeagleFury - 3D Design tools
Again, if the boolean operation was 'wrong' more than likely, your model was inside out. If your model is inside out, the boolean operations consider the outside of the model the inside, and the inside of the model the outside (Or, in other words, the boolean operations work properly mathematically based on the direction of the normals, but not as you had intended.) To get it correct, you haveby BeagleFury - 3D Design tools
MarcusWolschon Wrote: ------------------------------------------------------- > I gave blender a chance. > Multiple times. > But when I saw that the stable, release-version in > every debian and ubuntu > does intersection when asked to do union, union > when asked to do subtraction > and a very broken subtraction when asked to do > intersection I was gone. You need to makby BeagleFury - 3D Design tools
anton Wrote: > I've been trying to do some selftraining courses > in electronics recently, and stumpled upon a > section about induction, where he claims that > capacitance can be used to heat non conductive > materials, quite like induction can heat magnetic > materials, I've searched the net on how to do > this, but all I can find is melting capacitors and > burning holeby BeagleFury - General
> If almost the industry is now at +3.3V, we should > adapt to it. The same happens with that LQFP 0.5mm > pitch package, the others alternatives like BGA > are even worst for DIY. I don't have any problem using 3.3V, as long as noise can be managed; which means that with a 3.3V system, it becomes more important than ever to keep signal lines short, shielded, and away from noisy poweby BeagleFury - Controllers
reinoud Wrote: ------------------------------------------------------- > As for the Arduino Serial implementation, it has a > major flaw. The main problem is that receiving > sure is nicely done in interrupt and buffers etc, > but _sending_ is done in a busy waiting loop! no > buffering, no interrupt or whatsoever. If this > could be fixed, then it would be great. Yep. When Iby BeagleFury - Firmware - experimental, borrowed, and future
reinoud Wrote: ------------------------------------------------------- > Hi, > > looks good! I am currently working out a similar > scheme for the delta robot. Its nearing completion > :-) Sounds like we might have some opportunity to steal the best bits from each other's code then. > I've opted for a first setup/try to keep all > the calculations onboard the Arduino justby BeagleFury - Firmware - experimental, borrowed, and future
Only drawback to this device I see is the 3.3V basis; I assume all the ports are 3.3V as well? This has the issue of being more susceptable to noise... Any idea if there is a 5V equivilant, or alternatively, AKA47, any thoughts on using a alternative 3.3V + 12V lines for BEEF? If I understand TTL correctly, 3.3V lines should be able to drive 5V TTL, but vice versa is a bit riskier? (I.E, drivby BeagleFury - Controllers
nophead Wrote: ------------------------------------------------------- > There is a limit to how big you can go for a given > nozzle size. If you use a filament size that is > larger than the diameter that it swells to after > leaving the nozzle, then it tends to extrude a > zig-zag rather than a straight line. Also you > can't span gaps without some tension. Hi Nophead, Do yoby BeagleFury - General
Triffid_Hunter Wrote: ------------------------------------------------------- > BeagleFury, the hypocycloid design can be made to > have no backlash at all, as all the teeth can be > in contact with all the rollers simultaneously. > This is its advantage over the split annulus > epicyclic. I believe the split annulus with 5 planetary gears has 5 points of contact at all times (eveby BeagleFury - Mechanics
goinreverse Wrote: > Belts are a bit of a headache because you need to > properly size the pulleys, belt, bearings for the > pulleys to rest in and then deal with tension > issues. Just look at all the extra stuff on the > mendel design to handle that. The mcwire doesn't > really have any good place to put/mount all of > that. Fair enough. I guess I rate belt somewhat 'easiby BeagleFury - General
You may want to also consider trying a belt drive; put a 10 x .2" tooth pitch gear on the stepper, mount it orthogonal to the direction of travel off one side, mount an idle pully to the other side, then attach securely the belt to the underside of the platform. This is effectively what the current version of Mendel uses, and the timing belts appear to work quite well there. Rack and pinions haby BeagleFury - General
Triffid_Hunter Wrote: > Apart from that I've clocked my firmware at over > 35 Ksteps per second (50m/min @ 42 steps/mm), > where acceleration is paramount even with unloaded > motors. At this speed, the stepper shaft spins so > fast that it almost looks like an electric drill. > Here is the advantage of feeding 12v into 2v > motors Awesome. Gives me something to look forwaby BeagleFury - Firmware - experimental, borrowed, and future
Looking at the animation, it would appear that this design would have significant backlash unless you get very high tolerance on the gearing / pins. Is this my own misconception? Interestingly, the topology is reminiscent of the the split annulus epicyclic gear, where the top hypocycloid gears maps to the top half of annulus and planetary gear, and the bottom hypocycloid gears map to the bottomby BeagleFury - Mechanics