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Morgan, Wally, and many others too strange and wonderful to be described here. Previously named "Polar bots and Robot Arms"
Re: A Very Different Extruder - 4 years ago
Brilliant design! Might actually be light enough to convert my SCARA printer to direct drive. I have a 50 gram round NEMA14 I could use. And TMC2209 drivers, so I can adjust the microsteps to whatever works best. I'd prefer to use non-canted axles so I can make the carrier out of aluminum, but would all three rollers need to be threaded then since the filament would be getting dragged axially acrby dekutree64 - Tech-Talk
Re: Thermistor Extension Lead, Ender 3 - 4 years ago
Put heat shrink tubing or hot glue over the solder joints and they should be fine.by dekutree64 - General
Re: Scara Firmware Setup Confusion - 4 years ago
Yeah, homing is the most difficult part to get working because there's so much related code that it's difficult to tell what actually gets run and what should be run. I struggled a lot, but eventually got it narrowed down to just a few small changes: Conditionals_post.h line 182: Add #if ENABLED(MORGAN_SCARA) check around QUICK_HOME (in other words, don't enable QUICK_HOME) Motion.cpp lines 1318by dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Print Cost Calculator - 4 years ago
I wouldn't really consider there to be a life expectancy for the printer as a whole. Many parts wear out (PTFE tubes, nozzles, mechanical limit switches, belts, bearings, fans, leadscrew nuts, etc.) but all are replaceable. I'd make it a maintenance cost in dollars worth of parts and labor per 100 hours of printing time. Hard to guess what a typical value for it would be, though.by dekutree64 - General
Re: Z-Axis Resolution - 4 years ago
What sort of scenario are you envisioning where there would be a problem? If the printer hasn't already been homed, then the G0 will do nothing, and if it has been homed then it's going to a known-safe position just like every other movement during printing. Unless maybe if there have been missed steps on the way up due to some mechanical problem, but in that case your print would be messed up soby dekutree64 - Mechanics
Re: Z-Axis Resolution - 4 years ago
X and Y are quicker to move by hand. If you're worried about crashing, then make it G00 Z5 or something so it will stop with some distance to spare. If you just printed a 400mm tall model, and Z homing feedrate is set to the default 4mm/s, and rapid feedrate is 16mm/s, then you'll save over a minute of boredom.by dekutree64 - Mechanics
Re: Z-Axis Resolution - 4 years ago
Quotethe_digital_dentist Motors are only quiet if you use microstepping, Trinamic drivers will be as noisy as any other if you're driving the motor in full steps. Homing the Z axis at the end of a print is potentially disastrous. You might want to home X and Y to get the print away from the extruder, but leave Z where it is until after the print is removed from the bed. There's no need for a sepby dekutree64 - Mechanics
Re: Z-Axis Resolution - 4 years ago
Oh yeah, the noise problem does make sense. Not a problem nowadays with Trinamic drivers, though. BTW, a handy trick is to put a gcode file on your SD card containing only the command G00 Z0. After a tall print, run it to zip back to zero at full speedby dekutree64 - Mechanics
Re: Z-Axis Resolution - 4 years ago
AFAIK there is nothing special about the usual setup. The 8mm screw pitch seems reasonable since CNC machines probably use it for X/Y due to having lower friction/higher efficiency, so that's what was available cheapest and in large quantity when 3D printers were first being mass produced. But the microsteps make no sense. Some amount of microstepping is needed due to the numerical problem you mby dekutree64 - Mechanics
Re: Nema 17HS13-0404S Motor? - 4 years ago
Those are some odd ratings. Mine are 1.2amp, 48oz.in (which if my calculations are correct is 3.45kg.cm), and measured resistance is 8ohm. The 400mA I use is set in the Trinamic driver configuration. I'm not sure if it's per phase or what. The rated 1.2A is ok for intermittent/short duration running, and 600mA continuous would probably be ok if mounted to metal. But mine are mounted to PLA printeby dekutree64 - Mechanics
Re: Nema 17HS13-0404S Motor? - 4 years ago
The link isn't working, but from a search of the model number they are 34mm length? I have that size (used Shinano-Kenshi sold by tony34306 on ebay) on my SCARA printer and they seem plenty powerful. 400mA is about the maximum current before they start getting hotter than I'd like. The extruder works the hardest (Creality style non-geared extruder). I haven't tested the maximum throughput on it,by dekutree64 - Mechanics
Re: Noisy power supply fan - 4 years ago
Ah, should have checked youtube first. There are lots of videos showing how to replace the fan with larger/quieter types.by dekutree64 - General
Noisy power supply fan - 4 years ago
Before I rip into my power supply (standard 24V/15A kind found in most Creality printers and many others), I thought I'd check if anyone else has already solved this problem. With TMC2209 drivers and relatively quiet hotend/part cooling fans, I can't really hear any noise from my printer besides the obnoxiously loud whirr of the power supply fan. It's the kind that automatically changes speed basby dekutree64 - General
Re: Why you should power off when unattended - 4 years ago
I'm pretty sure those kind of stepper drivers run at constant current regardless of whether the motor is moving or not. With newer Trinamic drivers, current can be controlled by software, and set to a lower value when holding still. I always stick heatsinks on my stepper drivers regardless. And a fan for the ones on my CNC, which are that old style, and running NEMA23 motors which they're not reaby dekutree64 - Safety & Best Practices
Re: Looking for new contol boards and firmware - 4 years ago
I love SKR Mini and Marlin for low cost, but the Marlin source code is a nightmare to work in, and I think it will only get worse over time. Smoothieware code looks a lot nicer, but I haven't actually used it before. I've heard good things about Klipper too, which uses an interesting architecture where the main program runs on a Raspberry Pi, and the regular 3D printer motherboard (Arduino+RAMPS,by dekutree64 - General
Re: Scara Firmware Setup Confusion - 4 years ago
Spoke too soon! I've been doing more work on my printer, and after many hours of wading through confusing Marlin code, it turns out single-arm SCARA is indeed mostly supported, just lacking in documentation. First thing, in addition to enabling MP_SCARA in Configuration.h, you have to change Conditionals_LCD.h line 30 to #if EITHER(MORGAN_SCARA, MP_SCARA) Then use MANUAL_X_HOME_POS and MANUAL_by dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Extruder gear slips over the filament - 4 years ago
Pinch the extruder lever and push some filament through by hand and see if it flows out the nozzle freely. That should help sort out whether it's a problem with the motor or gear failing to grip the filament, or something further down the line causing excessive resistance.by dekutree64 - General
Re: Extruder gear slips over the filament - 4 years ago
Check the end of the bowden tube inside the hotend. Those tend to wear out relatively quickly, becoming warped and clogged. Just cut off the bad part and stick it back in, or buy a new one if it's too short. Make sure the end is cut square so it mates to the nozzle and doesn't leak plastic into the threads.by dekutree64 - General
Re: Scara Firmware Setup Confusion - 4 years ago
Yeah, that's the one I was thinking I'd buy if I can't figure out how to add the necessary calculations in Marlin myself, but it still costs almost as much as the rest of the printer. And true the STM32F103 doesn't have hardware floating point, but considering that Marlin's base CPU usage is low enough for 16MHz AVR, a 72MHz ARM ought to have plenty of cycles to spare for software float calculatiby dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Scara Firmware Setup Confusion - 4 years ago
After much procrastination, I finally got around to finishing construction of my printer. But now that I've got the firmware configured and flashed, I can confirm that Marlin does not have single-arm SCARA kinematics yet. So we're stuck with expensive Duet boards or nothing for now. Sad because SKR Mini has all the fancy hardware a SCARA needs for under $40.by dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Scara Firmware Setup Confusion - 5 years ago
Yeah, I do wish someone would write some documentation for this. The Marlin site says "Support for Cartesian, Delta, SCARA, and Core/H-Bot kinematics", and there are some config files here , but that seems to be the extent of the documentation. No explanation of what exactly is implemented or how to set it up. The original MPSCARA used a script to convert cartesian coordinates to polar coordinateby dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Heat bed stops heating within a few degrees of target temp - 5 years ago
Did you run PID autotune?by dekutree64 - Reprappers
Re: Brake vs. shorting stepper coils - 5 years ago
Dang, that's some rotten luck. I just bought a 1200mm T8x2 off ebay last week for $35 and it's straight as can be. It had foam pads taped around it, then placed into a tube with more pads stuffed into the ends, and then the tube placed into a long skinny box. Never had any trouble with 500mm screws off banggood either. But fair enough. The stepper motors with built-in brake would be nicest, butby dekutree64 - Mechanics
Re: Brake vs. shorting stepper coils - 5 years ago
If the bed is heavy enough to backdrive ballscrews, it's heavy enough to preload leadscrews. Use 'em. They're cheap, compact, and work just as well in this case. 1mm or 2mm lead.by dekutree64 - Mechanics
Re: Homemade single arm SCARA，How to setup the software - 5 years ago
MPSCARA has a python script for coordinate conversionby dekutree64 - Polar Machines, SCARA, Robot Arms
Re: Extrusion thickness 2040 vs 3030 - 5 years ago
It should stay flat if it's screwed to a 2x4 frame, assuming you can find decent wood that won't bend back and forth every time the humidity changes. And yes, it certainly will weigh a ton. If you want it to be portable, a self-supporting aluminum frame with corrugated fiberglass floor would probably be about as light as you can get. Plus no humidity issues like wood products. The fiberglass isby dekutree64 - Mechanics
Re: Extrusion thickness 2040 vs 3030 - 5 years ago
Yep, I'd skip the aluminum and screw the X rails straight to the bed. Print motor mounts that screw to the bed as well. If the Y motor rides on the carriage with its own belt to move the toolhead back and forth, then the X motors can be mounted with shafts horizontal rather than vertical, which would allow simple L bracket motor mounts.by dekutree64 - Mechanics
Re: Extrusion thickness 2040 vs 3030 - 5 years ago
Do you even need the aluminum? Seems easier and cheaper to build a frame out of 2x4 lumber, stick a sheet of MDF on it, and screw the rails straight to that. If necessary, raise the pen holder up from the rail slider blocks rather than raising the rails from the bed.by dekutree64 - Mechanics
Re: Wall Delta Printer - 5 years ago
QuoteVDX ... another viable conept with a "sideways" kinematic with low footprint and "foldable" arms is a SCARA or better a "parallel SCARA" (for higher accuracy and stiffness). Here is a good sample of a "parallel" - ... or here, a DIY type - I've been messing around with designs for a "wall SCARA" and I do think it's a better bet than delta. I'm hoping to keep the business end all up nearby dekutree64 - Reprappers
Re: Patents - 5 years ago
QuotegolfwolfWould I slow its weaponization, were I to publish my results in a different language than the colonizers' tongue? No, the people you're concerned about are an international group. And they have effectively infinite money, so being able to do something cheaply means nothing to them. Assuming the end result of your invention is the same as any other well made linear motion guide, thenby dekutree64 - General