OMG, tree #40 is printing now. Somebody either stop me or turn me into an elf.
I've been printing a forest of Christmas trees: https://www.thingiverse.com/thing:1913982, scaled to 33% to fit in the 101Hero and printed in spiral vase mode with 2 base layers using Cura 3.1.
Eventually I started to see some underextrusion due to my nozzle getting clogged.
I tried the "warm yank" method, where you set the hot-end temperature to about 50C, then release the extruder tension and pull out the filament. This worked well enough, but I was afraid that repeatedly opening and closing the 101Hero extruder door would wear out the screw holes way too fast.
What I'm doing instead is placing a pair of pliers (or anything metal) 1-2 mm below the nozzle then, at normal print temperature, extrude a small amount of filament to form a ball attached to the end of the nozzle (I use Pronterface to do the extrusion). Then I set the hot-end temperature to 30-50C, and when it gets there I pull straight down to remove the ball from the end of the nozzle.
This does a good job of cleaning the nozzle, with no need to unload and reload the filament.
I'm thinking it should be possible to do this automatically by printing a small part that has enough bed adhesion to resist the upward pull. Thoughts?
It might be best to try relevelling the bed.
Otherwise check the extruder control wires are able to move cleanly. It might be creating a bad connection.
as the title say, my kickstarter version of 101hero started to pring unevenly, meaning it is extruding more meterial when it's on the right side of the platform then when it is on the left one.
the picture is to show what i ment if anyone dosn't understand
P.S- sorry for spelling/grammer mistakes.
Some miscellaneous notes on keeping the 101Hero printing at its best:
1. Use glue stick.
The thing to take into account here is that the nozzle can easily push into a glue stick layer if it has to, and freshly extruded filament will still stick to the glue stick layer even if the nozzle isn't quite down far enough. I tend to keep my glue layer about 0.2 mm thick (one layer in draft mode), which seems to make mechanical alignment (and drift) much less of an issue.
2. Put acrylic sheets between each pylon.
This is the simplest single modification you can do to your 101Hero that has massive dividends. The acrylic sheet should be clear and thick enough not to easily flex (2.5-3 mm). The pylon has a V-groove the sheet can slide into, but the edge will need to be beveled for it fit snugly. Make a gig (or use a router) to shape the bevel, so it will be consistent on both sides of each of the 3 sheets. I started with the sheets slightly wide, then worked the bevel until I got a snug fit on all 3 sides. Make one side slightly looser so it can be raised and lowered for bed access.
Calibrate the printer once, and you'll only need to do it again if you drop it!
Once installed, the sheets not only make the printer much more rigid, but it also makes it much quieter, and reduces the effects of drafts in the room.
3. Use these glass plate clips: https://www.thingiverse.com/thing:2210718
Taking parts off the bed is the easiest way to knock the 101Hero out of alignment. Using these clips makes bed removal and installation effortless.
4. Print Calibration Towers
Both of the above include OpenSCAD files and Python scripts. I highly recommend using OpenSCAD to modify the prints, and avoid the Thingiverse Customizer. The scripts can be used in any version of Cura, but for me they were easiest to use in 15.04.6.
I print a temperature tower for every new spool, and/or when a spool has been sitting for a while. The main issue is that the temperature sensor on my 101Hero is not at all accurate (it has it's own private unit of temperature), so the temperature ranges printed on the spool are useless to me. I don't care what the temperature setting number is, I just want it to be whatever lets me print with high qualtiy: I just use the value indicated by where the "sweet zone" is on the tower.
I do a speed tower whenever I change anything mechanical, including both hardware and settings, or if I unexpectedly get a lousy print. All my prints to looked terrible after upgrading to Cura 3, the main problem being the pylon stepper motors were skipping steps despite printing at the same old speed that's worked well for me for months. The speed tower made it clear I had forgotten to reset the Cura 3 accelerations from the default of 3000 mm/sec^2 down to the 101Hero limit of 500 mm/sec^2.
These calibration towers should be your most frequent prints. They provide a consistent reference to help you find and fix problems. Be sure to keep all your old towers for comparison.
It will take some learning to create a custom STL in OpenSCAD, and to use the script to make the towers print easily and consistently. See my posts elsewhere in this forum for details. Though I use Cura 3 for all my regular prints, I still use Cura 15.04.6 for the calibration towers to keep everything consistent, and I don't use Cura 15.04.6 for any other prints.
Sigh. This entire thread is about trying to paint a turd gold. It may look better, but it will still be a turd. A shiny turd.
It is important (and also critical and vital) to realize that the 101Hero pylons, bed and arms DO NOT FORM A RIGID STRUCTURE! Precise mechanical calibration is totally useless. Close enough is good enough. Custom g-code won't make calibration any faster, better or easier.
Just the act of removing a print can bork the tower alignment. Changes in room temperature affect the entire printer structure, both in dimensions and stiffness.
That said, there are mitigations that are simple, cheap and effective. Please read my posts in other threads for the details. I'd recommend limiting the total investment in 101Hero upgrades to well under $20. Any more is just paint on the turd.
The next step would be improved firmware, but the printer is hardly worth the effort, since the gains will be small.
The 101Hero is an amazingly awesome set of ideas with very poor execution. There's no way to turn it into a great printer without replacing all the plastic parts. Such upgrades could be a great hobby project, but would also be a terrible return on investment compared to getting, say, a $99 BuildOne.
Edit: Well, that sounds pretty dismal, right? I want to emphasize that I LOVE my 101Hero! A better printer would not have permitted me to learn nearly as much as I have about the many ways prints (and printers) can go wrong, and the things that can be done to remedy the situation. This, to me, is truly the best and most awesome way to get serious about learning the nitty-gritty of 3D printers and 3D printing without making a major investment.
Last post by BobC -
Sorry, so long as you use the 101Hero plastic parts, you'll never have a robust printer. They're just way too flexible and sloppy, so other upgrades won't permit anything close to the expected improvement. If your heart is set on a small delta, start with a mini-Kossel frame and build from there.
I think all the ideas in the 101Hero are great, but their execution is poor. A stiffer frame (I added acrylic sheets between the columns), higher quality motors (I got mine from the group buy), and rubber bands on each end of the arms will fix most of the problems for a total cost under $10. Any further upgrades will have diminishing returns.
However, rather then do major upgrades to the 101Hero, I'd recommend getting an inexpensive Cartesian printer, such as the BuildOne by Robotic Industries (which should ship soon after Chinese New Year). It will print 7x-10x faster than the 101Hero, and the base printer is just $99 (before tax and shipping). The base model even includes automatic bed leveling. And it can take a world of accessories and factory upgrades.
Still, once the 101Hero is no longer my only printer, I will probably consider doing some serious hacking on it. I'll start with adding a 2020 extrusion exoskeleton and metal/carbon arms. Then maybe a new carriage and hot-end, with conversion to a Bowden feed. We'll see....
Your base is installed upside-down! The smooth side goes up.
Last post by BobC -
I think the key is developing a consistent system for problem detection, correction and prevention.
Whenever I change the filament or modify the print settings, or simply haven't used the printer for a while, I always print a Temperature Calibration Tower (done today because all my prints went bad - it was due to lower room temperature):
Whenever I change anything that affects the printer mechanically, such as the printer configuration or a motor replacement (today!), I always print a Speed Calibration Tower:
I recommend installing OpenSCAD and modifying the .scad files directly, then generating the STL. The Thingiverse Customizer is badly broken and takes way too long when it does work. But do take a quick peek at each tower in the Customizer to learn about the model parameters.
Each model comes with a Python script to modify the Speed or Temperature with Height. These scripts were easiest for me to install in Cura 15, though I use Cura 3 for everything else.
To keep things as fast as possible, both towers are printed in vase-mode, with a single wall, 2-layer base, and no top or fill. Be sure to print the Temperature Tower at a slow speed, 6-8 mm/sec, so the hot-end has time to reach the new temperature before too many layers are printed. (I keep meaning to try using the "Pause at Z" script for this, but I haven't yet looked into it.)
Start the Speed Tower at something like 8 mm/sec, and increase by steps of 1 mm/sec. A step height of 8 mm gives enough steps to cover the entire useful range.
Before starting the print, be sure to always set the speed and temperature as appropriate for the first step of each tower.
There are other things I should mention about the towers, but they aren't coming to mind at the moment. Please let me know if you have problems with them.
The 101Hero has too many sources of vibration and wobble. But they can be managed!
A big part of the problem is the crappy stock motors. The gearing can start sloppy with lots of grinding, and only gets worse from there. High-quality replacement motors are recommended! After the motor replacement I did today, my Speed Calibration Tower shows my useful draft printing speed has gone up to 17 mm/sec! (Clean/fine prints still need 8-10 mm/sec.)
Another factor is that the entire printer frame is unstable. It can get canted just by removing a print, and can wobble during a print. I added acrylic sheets between each column to serve both as stiffening and as an enclosure. But even this doesn't fix things well enough. When I start a print, I always use at least a skirt (or brim or raft) so I can nudge/twist the printer legs until the lines look right. If the print starts before it looks right, I abort, clean the bed, then restart.
The ball joints also have lots of slop and the arms are too flexible, both of which can cause print distortion. My solution is to add snug (not loose or tight) rubber bands at each end of the arms (NOT in the middle!). Made a HUGE improvement for me!
Then there's the spool: The spool holder must fill the entire center of the spool and have very smooth rotation, else the tugs of rotation will cause the print carriage to be pulled and jerked around. The best (and cheapest!) solution is to use a paint roller (described in another of my posts somewhere on this forum).
Finally, the firmware needs an update, especially the internal configuration constants, and particularly the arm lengths. I've been meaning to look at this, but it will take a ton of time to get done, so it hasn't been a priority.
FWIW, I find glue stick works best for bed adhesion. Tape is too fussy, hair spray is too messy.
Last post by Chaloux -
Thanks for your insights. Helped me a lot to make the final decision.