Anyone familiar with a glass from Schott called "Robax"? Apparently, very low thermal expansion and very high temp. Used for wood stove windows. American Science and Surplus (worth visiting, just for the fun of the unusual stuff they sell!) has 12" X 9" X 3/16"" inch windows (strange shape...not clear what the dimensions refer to...) but pretty darn cheap ($3.50 each). Web search indicates Roby mars bonfire - Reprappers
If I understand what is being proposed, slip should not be an issue since the cable is anchored on one of the drums. The subtley there might be one of multiple turns on a given drum "slipping" or better put as jumping over another turn. This can be tamed, I believe with using a cable with reasonable diameter (not overly "fine") so that it lays up on the drum in a smooth, constant diameter fashiby mars bonfire - Reprappers
Conjecture on why the prevelance of cogged belt drives on repraps: I spoke with an mechanical engineer friend with lots of experience designing cartesian "movers" in this size and accuracy range. His "go to" design would be cogged belts...straightforward, readily available parts, well understand (not perfect, but understood). I asked about cable drive....offered tradeoffs I described above butby mars bonfire - Reprappers
By control line, I take it to mean what might be called a "cable drive" i.e. a cable or line wrapped around the driving "drum". One end of cable would be hard fixed to the drum. This setup in contrast to what might be called a "drive belt" drive i.e. not wrapped around the driving pulley and not fixed to the pulley...like a fan belt in a old car. So given I have the right idea and the questionby mars bonfire - Reprappers
Traumflug, Thanks. Exactly what I needed. Steveby mars bonfire - Developers
I am building my own version of a hot end to extrude ABS 1.75 mm filament. While I realize that this question has a lot of complications (specific design, materials, insulation, rate of extrusion, etc....), I would appreciate if someone could give me a ball park number for the power in watts needed for the hot end...something like you probably need at least XXX watts and don't think you would neby mars bonfire - Developers
Overkill...sure, obsession or healthy fun? No claim on my part that anything like this is even close to be being needed...many ways to slice a watermelon. Steveby mars bonfire - Reprappers
Thought I would share my design for a heat sink for the Pololu Stepper Driver board. This is the driver board based on the Allegro 4983 (now 4988) chip. I am using the version that requires a external logic supply (no on board regulator). I want to use the board to run 1.4 amp steppers therefore needing to add heat sinking. I took an approach that seems to be less common than the usual tact oby mars bonfire - Reprappers
Can someone kindly describe how these two pieces of software (Pronterface and Redsnapper) relate/fit into the toolchain? Am I correct that they both seem to perform the same basic functions? Thanks, Steveby mars bonfire - Developers
Has any consensus emerged on what are the choices for a heated bed for ABS printing in order of cost of materials... Basically, if you have unlimited funds, use XXX, down to if you want to go cheap, use YYY. I have surfed around in the various notes and forums and there seems to be everything from somewhat exotic glass to aluminum with painter's tape...and it seems like an active area for furby mars bonfire - Developers
Thanks! That helps greatly. And as I was writing this reply, I realized that what I first took as a hyphen in your answer was a minus sign (doh!)...makes total sense. And yes, it is an extruder design with a pretty large ratio reduction ratio stepper drive (cogged belt). So slow on the extrude should not be a problem.by mars bonfire - Developers
I have been slowly but surely working on a Millstrap based on my Taig CNC mill for XYZ and an extruder design based on the mini-extruder. I have posted mini-extruder pictures previously. But...it is feeling lonely out here! A few questions: * Anyone further along on a Millstrap than I am? * I am getting cold feet about the ability to have the mill move fast enough when I actually get this lby mars bonfire - Developers
Extruder for my mill strap design. Most of the extruder construction is complete, but have not "fired" it up (probably should not say fire). Plan is to attach to my Taig CNC mill as the XYZ mover. Lots of the the extruder stolen from mini extruder design. Definitely not reprapish in that it is all metal. Somewhat unique feature is that (can't see it in these pictures) is that the brass nozzby mars bonfire - Developers
I am building a reprap and in the process, starting to figure out the software toolchain. I would appreciate if someone could explain a few things: * If I understand correctly, a typical approach would be to use some 3D design package to design the part and output a .STL file. * (the mysterious part)...The .STL file goes into a piece of software that translates this into G-codes. *The g codby mars bonfire - Reprappers
Viktor, Thanks for answering my question. I was hoping that was case. Steveby mars bonfire - Developers
I have been studying the Mendel "stable" firmware....what does an "internal extruder" mean vs. an external extruder? This relates to whether a single Mega Anduino can host both movement and extruder stepper control...or is the firmware structured only to support two separate microcontrollers...? TIA, Steveby mars bonfire - Developers
May well have already been covered but I thought I would share a method that I experimented with this weekend to make the friction drive wheel for an extruder. Based on some reprap research, looks like people are using the hob method (use a threading tap to hob teeth into a bolt...sort of like hobbing a worm gear) and others, using a press in insert that has gripping ridges. I have a CNC taig mby mars bonfire - Developers
I have been wandering through the reprap wiki, trying to figure out a path to a 3D printer for my particular interests and resources. I would appreciate comments and/or design review of my proposed plan. Here goes: Since I own a small 2 1/2 D Taig CNC mill, I will start with that for the translational axes. So I understand this would be called a Millstrap. I am designing a variant of the minby mars bonfire - Developers
Sorry...made a mistake. Looks like PEEK works to 480F, not 400F as I stated. McMaster lists Rulon LR to 500F and others list Rulon LR to 550F...bottom line, PTFE and PEEK work, supported by specification and actual use, Rulon LR by spec and maybe, hopefully, by actual use. I will check in once I get something working...by mars bonfire - Developers
Wade, I think you got a good deal on the PTFE and I got a not so good price on the Rulon LR. Actually, I just ordered a 12" long rod from Small Parts (3/4" diameter) for $26...it almost looks like a misprint...smaller rods are more expensive!. I was thinking about PEEK but what tilted me toward the Rulon LR was that (in addition to it being inherently low friction), it has a working temperaturby mars bonfire - Developers
Only a week or so into planning my 3D printer build....if this is old news, hit the delete and please let me know if this post is not appropriate for this forum. Anyhow, I have been researching the various extruder designs and specifically, the material used for the thermal "standoff" i.e. the barrel section between the feed pusher and the hot tip. The material of choice seems to be PTFE (tefloby mars bonfire - Developers
Newbie alert. If I need to read some faq or other source, please kindly direct me to such. With that preface, I am starting a reprap machine, using a unique 3D mechanism that I got out of some hi tech junk...one of kind but three nice orthogonal axes and a positional envelope that is pretty darn appropriate...and built like a brick root cellar. 3/4" hardened rods, recirc ball slides, ball beby mars bonfire - Reprappers