OK, for 2 weeks now I've done everything I can think of, gone through the calibration section numerous times, read every forum post I can find yet still cannot get my Dual calibrated and printing. My first problem is that I could not get the Estep calibration working no matter what. Right now I'm just working with the left head and setting things up per the build guide, loading defaults and trying to extrude 100mm of either PLA (at least I think it is PLA since it is what was sent with the kit and there's nothing to indicate what it is) or ABS results in the same issue. The filament starts to feed then stops, restarts, sometimes jumps and many times the hob chews half way through filament. I've tried temps up to 220 on the PLA and 260 on the ABS with no luck. The only way I could get it to reliably feed 100mm of filament was to modify the Gcode to change the feed rate from 200 to 50. I was able to use the slower speed to go through the measure, feed, calculate, update Estep retest cycle until I can reliable feed 100mm but ONLY at the slower speed. Thinking I at lease had the feed calibrate I've tried using S3D to print a 20mm test box. I've done the IR calibration with the belt segment numerous times and done the bed leveling even more times using thinner and thinner pieces of paper yet when it goes to print the filament will not stick and everything gums up on the head. I've tried different bed temperatures, cleaning the glass throughly to remove finger oils, blue painters tape and even 30 minute temperature soaks per other forums on 3D printers trying to get filament to stick. I can't help but feel that the may revolve around my inability to get the filament calibration to work with "normal" feed rate but I'm out of ideas. Also, just to make sure. Using S3D I select "other" from the printer choices, load the dual.fff and change temps and stuff for the material I'm playing with right? Suggestions? Ideas? Forum posts that might address this? (I sure as h$^& can't find one) Any help would be greatly appreciated. It's very frustrating to be so close and to see what others can accomplish with their Duals yet I can't even get a single print head to work. Thanks for your time and any help you can provide.
So you have 2 problems... calibrating the extruder bed adhesion Looking at your extrusion behaviour it very much looks like your stepper is missing steps when running at higher speeds. Did you check the voltage of your driver ? If the voltage is ok (it should be somewhere between 0.5 and 0.6V) switch the drivers of stepper 0 and 1. As for the bed adhesion, what is the distance of your head at start ? Can you post some pictures ? Did you use Uhu stick of hairspray ?
Three suggestions: Does your filament run straight? http://wiki.e3d-online.com/wiki/File:Dual_grub_tight.jpg Did you mount the extruder idler correctly (too much pressure or bearing in wrong position)? Did you mount the inner PTFE tube correctly (clean cut, length 66mm)? http://wiki.e3d-online.com/wiki/File:Clip_up.jpg
@Rob The stepper rarely misses a step but will on occasion. Most of the time the gear chews through the side of the filament and I have little slivers of filament on the gear hob and in the idler area. I'm pretty anal about settings and stuff so made sure I set all the steppers to the mid range of 0.55V. I have them all within +/- 0.01V. Not sure what you mean by "switch the drivers". I'm also not sure how to answer your "distance at start" question and photos request. Are you talking about distance when after it homes? Distance with it starts printing? I guess I'll try the glue stick and then hair spray tricks next although I'm curious why many don't seem to need it while others it's the only thing that works. @K2B Yes, I did the "running the section of filament on a loose hob back and forth" to center the hob. I "think" the idler is correct. The filament seems to be running in the middle of the bearing. How do you know what the proper pressure is? I didn't see anything in the build instructions on how to set it. I'm 99.99% certain I got the PTFE tube right. Measure twice cut once. Got a PM regarding the head so I may just tear them completely apart (again) and reassemble just to make sure. Thanks to both of you for your assistance.
I meant swap the stepper drivers from extruder 0 with extruder 1, see if the problem is stepper related. This is the distance of the nozzle above the bed.
Still not sure what you mean by "swap the stepper drivers". Are you saying the built-in drivers on the Rumba board are movable or are do you mean to swap the cables and tell S3D to use the right head so that I'm driving the left head but plugged into the right heads output on the Rumba? Regarding the distances. Here's a shot of the clearance when homed: Here's one once it starts printing: I loaded Alex9779 FFF config and have been experimenting with it and have managed to get a bit further. I was able to sort of print getting adhesion to the painters tape but I don't know what is causing all the voids. I can extrude cleanly and without issue if I feed using the extruder feed command in the Prepare section yet when I print the extrusion isn't smooth. I also tried using the glue stick and a different temperature for the ABS and got this: The dimensions of the test box seem close to what it should be but I'm not sure of the cause of all the voiding during printing. I'm thinking temperature setting as the feed rate seems to be OK without any stuttering. I guess I'll keep tinkering around temps and the like to see what happens.
Another thought, as this is really strange: Did you drill the cable spines? On my BigBox they all were too tight, pressing the tube too much. Just try once to feed the filament directly, without using the PTFE tube.
You can indeed move the stepper drivers. I did replace one because I did have problems with my Y-stepper driver. As for the voiding during printing, it looks like you are printing too fast or at a too high temperature, or your fans are not running. Your cooling setting should be something like this: Especially when printing small objects like the 20mm cube the Adjust printing speed for layers below setting is important.
@K2B: Fortunately I spotted that on the build. While doing the prebuild subassemblies I saw that the extruder body had a bit of a problem. The feedthroughs were badly printed and actually closed off. There was no way to feed filament through. I took a 3mm bit and cleared the holes and tested with the PTFE. Using Alex9779's config is actually letting me print (sort of). I tried printing 3 calibration boxes but they all turned out like the photos above show. I switched over to some of the filament that came in the kit thinking I may have a filament problem. I've used the ABS filament with great success with the Polyprinters at the Makerspace I used to be a member of. Printing with what I believe is the white PLA that came with the kit (not sure since none of it was labelled) I kicked off the 3DBenchy gcode on the SD card and wound up with this: Looks like it isn't filament but more likely a setting or settings of some sort. It's like the full amount of filament isn't getting extruded: @Rob: Thanks for the clarification. I had no idea you could do that with the Rumba and drivers. I believe I have sort of a handle on the drive now and in 20mm test box prints I did have the fans turned off as I never had or needed them on my Thing-O-matic (that still runs actually but prints poorly hence the purchase of the Dual). I don't remember there being a fan on the Polyprinter so thought for such a small part I didn't need the fans as they were needed to control warping etc on larger prints that retained heat. Since the file on the SD card does control the fans I don't get the voids like on the test print but as you can see above it looks like the extrusions are too "thin". I backed off on the tension on the idler and don't see any more slivers but still aren't sure where the sweet spot is. I'm thinking the above photo leads even more credence to your statement that it is printing too fast but that's the speed in the gcode on the SD card so I figured the printer must be capable of printing at that speed. Do you know if I turn down the Fr on the LCD if it affects ALL feedrates? I was thinking of turning it to say 50% but if it's a function of filament feed rate along with X and Y feed rates the ratios would remain the same i.e. slower X and Y but slower extrusion rate also. I may try it just to see what happens. Thanks again to both of you for helping.
Annnddddddddd. . . . . it didn't work. . . Printing with a Fr of 50 had no effect on the width of the extrusion.
OK, based on digging through forums for the last hour I believe I have a PID issue based on the wavy lines in the Benchy print and looking closely at the photos. Found something in the forum regarding kicking off an auto-tune via the terminal but as usual cannot for the life of me find it so I can reference it for any other noob like myself to use. The too thin filaments are under extrusions maybe? Will try to address that next after straightening out heater tuning.
Your last prints of the benchy look very much like under extrusion. Did you calibrate your filament ?
There is feedrate (overall factor) and flowrate. The latter you want to modify. In your case I would also inspect the nozzle whether there is some dirt inside. A result like yours is pointing out to some hardware problem.
Well crap. I thought I hit "post" on this last night. Anyhoo, thank you for the suggestions but it "just started working". I have no freakin' clue what I did other than auto-tune the PID and then go back and auto-level about a dozen times and added the fan settings that Ron suggested but all of a sudden my printer is now capable of printing the 20mmx20mmx10mm calibration block: and I really wished I understood what I did so I could pass it on to someone who may be having problems. Thanks again for your suggestions and willingness to help.
