jdudeo

Thanks for the explanations I think I've got a much better grasp on this problem now. I printed the extrusion test, the problem appeared at around the 8mm/s mark but by increasing the temperature to eventually about 255 I was able to print the whole thing successfully. I'm trying my print again now at 230 and it seems fine so far, I guess I should have done more troubleshooting before posting here but it seemed so odd and I had no idea what to search for. About the spool holder design I would like to try that out, currently I'm printing my own free standing spool holder design but it would probably be very efficient to incorporate that low friction design into it.

Robert it sounds very likely that that's what I was experiencing, I've uploaded a video: What seems strange to me though is that it starts off fine, if it can extrude properly at that speed for almost an hour then why does it suddenly start doing that part of the way through? And even if the speed and volume is the problem what is the rationale for that movement? What code is causing this? Also I can't confirm that it's the same problem but I printed a much larger object, I was there for the first 2-3 hours of printing then I went home and left the printer to do its thing. When I came back in the morning it had improperly extruded layers and clean properly extruded layers both at once (as in some clean layers managed to happen after dirty layers) I thought it might be a problem with the filament spool not rolling properly and the filament getting stuck (I'm not too fond of the Ultimaker 2 spool holder because of the distance it leaves between the machine and spool causing the extruder to pull the filament sideways) but after what happened today I thought maybe it might be this same problem. Nevertheless I'll try printing slower and see if the problem persists.

I'm having a strange problem where my print starts out fine, but mid-way through the extruder periodically pulls back on the filament like a retraction but doesn't push the filament back through the nozzle, it just continues extruding at the same rate, creating really stringy prints. It would appear that this is a problem with the G-code but I don't know why such retractions would end up in there, it happens even if I'm printing a model that doesn't require any retraction at any point. I'll post a video and pictures in a few hours but for now here are my Cura settings...

I also do 3D graphics for a living and have been doing it since I was 14, I worked about 5-6 years in 3DS Max and the rest of the time in Cinema 4D. Out of all the forums and discussions I've seen over the years this is the first time I see anybody claim they can cut NURBS and splines out of their workflow (replacing it with box modelling??). Do you realise that objects created with NURBS can be turned into editable polys and be used in booleans? Do you know that the meshsmooth modifier people often use with box modelling is actually generating a NURBS surface? Which can then be turned into editable polys? I don't see how this is a question of either/or... One thing I've experienced though is that booleans should be avoided unless there's no other option. Chopmeister is right about what they do to geometry and the unchamfered and not easily meshsmoothed edges generated are too harsh to fit prominently in a photo-realistic environment.

A telling statement if there ever was one, this ain't worth it...

How much do you know about 3D? Have you never heard about NURBS and spline sweeping? I don't know what the original poster would do with the lines but when sweeped they would be sliceable, though it seems meaningless. I imagine this function could be used to check if a print fits with another print (parts that are supposed to interlock or slot together etc.) or to change the automatically generated support in some way. And this was a discussion fundamentally about converting support material and infill to be part of the 3D model, to me this seems doable with the method I proposed.

what about the possibility of exporting the path of the extruder as one long twisty spline? Or two splines where one is the path while extruding and one is just the moves. It would then be easy to sweep it NURBS style in one's preferred 3D package and it would look exactly like the final print infill and all.

Ok thanks, what about the fan, is it ok to run it without the fan attached? If I do find that the voltages are wrong, where am I looking to solder?

would it be possible to get some more hands-on help with this possibly over Skype or something? I've borrowed a voltmeter and opened everything up, figured out which pin is which with the EAGLE software but I don't know where I should touch with the voltmeter and if I'm ok taking the fan off etc...

Ok it must be a problem with the DIR signal then. I will get a voltmeter and investigate. Thanks for your help with this.

ok thanks gr5 I will purchase a voltmeter and try that out, I seriously doubt it has to do with the limit switches but I'll double check those anyway and report back. The main reason I'm doubtful about the limit switches is that as far as I know they could only stop the head from moving instead of sending it travelling the other way, the problem also occurs regardless of where the printhead is and as I said if it hits a limit switch while it's going the wrong way it will continue to travel in that direction. Just to be specific, the green board I'm referring to is this: https://www.ultimaker.com/products/electronics I previously tried switching the stepper drivers with the problem remaining on the Y axis which is why I think it's the board itself not the drivers.

sorry for the really long delay with my response. I ended up ordering a new Arduino and put that one in but the problem persisted. Is there a chance that the problem is with the green board that interfaces with the connections to the steppers and such? I can't think of any other cause, this problem has been really demotivating and my printer has just been sitting inactive for months..

Ok well I tried switching stepper drivers also and the problem continued to be on the Y axis, so I guess it's not a problem with the drivers but with the board. I'll order a replacement and try that. As far as it being a problem with the end switches I'm skeptical, since the problem occurs regardless of whether it's anywhere near the ends and if a switch was triggered wouldn't that just cause it to stop moving rather than go in the opposite direction? Nevertheless thanks for the help with this.

If I order a new arduino, does that mean I'll have to solder all the ports from my current one onto the new one? I don't know any electronics but it seems I might be better off figuring out how to check the voltages on my current one.

Hey, sorry to bring up such an old thread. I just had the time to try fixing this problem with the Y axis. As suggested I double checked that all pulleys were tight and then tried switching the X and Y steppers. The problem continued to be with the Y axis. I think it originated in the arduino because the stepper itself is actually turning the wrong way. I'd be grateful for any ideas on how to fix this, I googled potentiometer but couldn't find anything on the board that looked like one. By the way I didn't see any black heatsinks on the stepper drivers. What's strange is that sometimes it turns in the right direction and sometimes it doesn't, it also seems to get worse when the machine is on for longer but it's hard to verify that.