@ Solidus Labs A few questions: How many teeth on the worm wheel? Does the code need the quantity of teeth, or a ratio in order to work correctly? I'm curious how rigid the worm drive delta printer is, please make a video. Power up the bot, and with your hands push on the end effector, does it feel solid? It looks to me like the forearm is longer than the upper arm. With unequal length arms, aby A2 - Delta Machines
Quotenicholas.seward The worm drive results in a non-linear graph of stepper rotation vs actuated distance. Ok, that's what I was thinking too. Solidus Labs created code to account for non linear aspects specific to the worm drive, makes sense.by A2 - Delta Machines
@ Annirak Ok, thank you, and it's good to learn that the non linear problem is not inherent with the worm drive!by A2 - Delta Machines
QuoteLoboCNC The other good application for closed loop control would be printers with screw drives For worm gear drive delta printers, an encoder mounted on the pivotal arm (not the motor) would help solve the backlash! Worm gears are notorious for backlash. A kit consisting of 4 encoders would be great for worm drive delta printers. 3 encoders for the A, B, C axis stepper motors, and 1 encodeby A2 - General
@ nicholas.seward I think Guizmo bike cables are proportional. As one leg shortens the other leg lengthens, how is that not proportional? @ Guizmo There are bike cables that use solid wire, vs. braided cable. I think a solid wire would negate any buckling that a cable my exhibit. I think you need to add a circular wheel to the lower pivot to maintain geometric form. As the cable is lengthenby A2 - Delta Machines
9:21 am computer time Posted time now = my computer time!by A2 - Sandbox
QuoteTraumflug I'll follow you here when the stepper is replaced with a DC motor. For a given torque, does a DC motor use less energy? Does a DC motor cost less? Is a DC motor size significantly different? Can you provide a link to a DC motor that would be a substitute?by A2 - General
I would like to see this project move forward. I don't know what's involved to make this work. Can you contrast your project to this encoder: CUI Inc, AMT102, $23.63. Capacitive Encoder: CUI Inc, AMT102. 8192 counts/rev or .04 degrees resolution Digi-Key Part Number 102-1307-ND CUI Inc, AMT102 Encoder Installationby A2 - General
@ Guizmo Remote Drive GUS (RDGUS) Very cool! >< I also like where you located the end-stop on the worm wheel. I imagine to rotate the pillar you will need to mount the remote drive, and the pillar onto a common lazy Susan? If the bike cable is long enough, I can envision the pillar rotating without having the worm drive mounted to it. To make it a SCARA robot, the end effector needs aby A2 - Delta Machines
@ nicholas.seward Does Solidus Labs code solve the non linear problem for the block, and tackle (GED)? If the problem is solved, please integrate it into your code, as I still wan't to build a "found" GED! If the non linear problem persist, what changes are required? A2by A2 - Delta Machines
Yoo-hoo! Looking forward to your validation print! Please add notes to your code so I can learn from your work! Tks! A2 QuoteSolidus Labs I believe I have most of the kinks worked out of the firmware. Right now I am working on getting all of the movment calibrated. Appears to be decent challenge. Here are a few test videos: http://www.youtube.com/watch?v=_qVeYwdC59g http://www.youtube.coby A2 - Delta Machines
@ leadinglights "Having said that, there is something refreshing about using words most likely to be understood by the initiate - even if this is quite often ambiguous." In some fields, or at a low level, I guess that would be OK. But in the case of statistics, it's very upsetting, even maddening. In my studies I found a PhD professor complaining about this in a paper. He provided an exampleby A2 - General
@ nophead Agree, an example based on your definition: on a screw, the flat of the flight is called the "flight lands", and it has a close relationship with the I.D. of the barrel. Land (Gate Area): Gate dimension parallel to the direction of melt flow. Land. A term used to describe the area in which the gate, or vent, resides. Land Area: The area of surfaces of a mold which contact each otby A2 - General
Hot end = Die. Die face = planar end surface = end wall = The surface adjacent the orifice. Die angle = An internal taper which is located ahead of the land (e.g. the 118 degree drill angle). Barrel = The region before the die angle. If the external profile of the die (hot end) is tapered, then the geometry of "die face" is called a frustum. Orifice entry dia = Throat (i.e. the radius featurby A2 - General
Delta bots are scalable, I and a few others plan to build a 1 meter 3D printer, and larger. Our problem today is that the software to drive an inverted delta robot is not able to print accurately. A few of us are working on the machine design, and more importantly the software. If your product "fits air" (i.e. accurate reproduction of geometric form and dimensions are not important), as most extby A2 - RepLab Working Group
Dielectric Fluid Sinker Dielectric Fundamentals: • The dielectric oil acts as a medium through which controlled electrical discharges occur. • The dielectric oil acts as a quenching medium to cool and solidify the gaseous EDM debris resulting from the discharge. • The dielectric oil acts as a medium used to carry away the solidified EDM debris from the discharge gap to the filter system. • The dby A2 - General
This video instructional looks simple: Make a doorbell EDM machine to burn small holes into the nozzle. You could even burn the ID profile! Use a dielectric fluid, and a plastic guide for the electrode. Use a sewing needle as the electrode. Originally posted in this thread:by A2 - General
Ideas: For ease of manufacturing just use two bolts, and use anti-seize on the thread. SS contacting aluminum will corrode, the anti-seize will help slow it down. For experimentation purposes, begin as davew_tx suggested with 10 mm deep hole in the copper hot end. I would only use a glass face seal, don't embedded the glass tube into the hot end (only use a face seal/contact). With the glass outby A2 - General
Why does 3DS MAX, and Blender rescales the .STL data file? Any other CAD software doing this?by A2 - General
You could use CPU thermal compound to help transfer the heat.by A2 - General
Consider running the bolts through the upper manifold and secure with a nut. Locate a compression spring (washer spring, cup spring) under the nut to help maintain a constant contact force. Springs can be stacked to increase compression force. Maybe brass wool could be used as a compression seal, expansion compensation at the top. To help prevent leakage (if it's an issue): If you're able to grby A2 - General
Land length: (3) The surface of an extrusion die parallel to the direction of melt flow. Land. A term used to describe the area in which the gate, or vent, resides. It can also be thought of as the ``length'' dimension in the ``l, w, h'' terminology used for describing the dimensions of the gate or vent. Land (Gate Area): Gate dimension parallel to the direction of melt flow.by A2 - General
"To my great surprise. In a nearby store for gardeners I discovered rod of 1.8 mm PET. It was a rod for trellising vines."by A2 - General
@ leadinglights "Now all I have to do is get my technique right for drilling the orifice from inside the nozzle. Having broken all 4 of my 0.35mm drill bits I am having to try to sharpen the best of them. " Make a doorbell EDM machine to burn small holes into the nozzle. You could even burn the ID profile! Use a dielectric fluid, and a plastic guide for the electrode. Use a sewing needle as thby A2 - General
Land = "between the die face and the converging surface"by A2 - General
@ Robin2 Read the patent snippet that I posted, and look at the patent drawing, they use the term "land". I'm accustomed to using the term land for a feature that is located between two different geometries. Orifice length sounds like the same thing. @ thejollygrimreaper has pointed out a very important nozzle feature, that of being flat, and no burrs. The face of the orifice must be flat and pby A2 - General
@ leadinglights "My best guess is the word "land" applies to how long the orifice hole is." Correct. The longer the land, the greater the pressure required to extrude. The shorter the land, the less pressure required to extrude. A zero land length in theory provides higher performance, as it would be more responsive to the on and off pressures. I suspect that printing surface irregularities mby A2 - General
Reading this made me think that if simultaneously the hot end could move in X, Y independently of the table X, Y, could you get closer to a constant velocity, or could it help in some other way? This is not my field of expertise, far from it, but it sounds interesting! By the way, anytime you are using both X and Y motions, it pays to split up the problem. Move your tool in the X direction anby A2 - Delta Machines
Plating > .001 inch will exacerbate surface roughness, and would need to be ground. Hard chrome plate can be applied to .0002 inch. You want your surface finish to be very smooth, ref: RMS 4 to ~8 is a mirror. I personally wouldn't worry about drill rod tarnishing, periodically wipe it down. Don't touch the metal with your hands. I would be more concerned about the straightness. 304L SS is sby A2 - General