Plastic Spaghetti

[suecottingham]

My 7th grade life science classroom is part of a study with a local university on the outcomes of 3D printing on students and their 21st century skills. We have gotten a Maker Bot 5th generation printer and it has worked beautifully from October till this week. Now I am getting, for lack of a better term, plastic spaghetti or “hair” on student prints (see pictures below). Parts will print normally and others not. Sometimes rafts are on when this happens some times they are off, there does not seem to be a pattern, or at least I haven’t found one yet. The students are designing with Tinkercad and Tinkercad support people have said to use D to drop every single shape on the plate (which I do personally) and Maker Bot support has said to lower the temperature and make sure rafts are on, which I have done. Even when I put the rafts on, when I hit print, the rafts go off and the resolution mm go to 0 which I know are wrong. I would have just changed it BEFORE I hit print but it doesn’t ALWAYS stick.

I know we are new to this but Tinkercad suggested this forum to see if anyone else had any ideas or had encountered this issue. You all come very highly recommended!

Thank you in advance for any help you can provide for my students.

Dr Sue Cottingham

7th Grade Life Science Teacher

[ch4s3r]

I would suggest resetting to default setting in your makerbot software in the print settings menu. Then run the initial setup utility on your makerbot itself, follow the steps through the bed leveling ect… Perhaps this will correct the issues. Also there are lay flat and place on bed functions in the makerbot software that should be able to auto rotate and optimally orient your objects to reduce any floating. Hope this helps!

[3DecorRVK]

Hi Dr. Cottingham,

What is the temperature your extruder is set to? One thing you can try is first unload the filament you have in your extruder. Then pre-heat the extruder at a temperature a bit higher than the normal print temp of the filament you are extruding (for example if you print with ABS at 230c try preheating at 235-240c). Then try reloading your filament to see if you get a steady flow of filament. Then try doing a couple of test prints to see if that makes a difference.

If that doesn´t work you may have a blockage in your extruder, at which point you would need to clean your hot-end by submerging it in acetone for about 15 -20 minutes, and looking for/clearing any physical blockages in the extruder, which may require you to detatch/re-attach the extruder from your printer.

I hope you get a better flow with one of those two suggestions, if I can think of anything else I will post it here. Take care and best wishes!

Ty

[Andrew_Dowling]

Potential problems:

1. Your first layer isn’t sticking right. your initial Z axis probe isn’t registering correctly. The result will be almost 100% what you see above. My solution now is to grab that lead screw on the back, and manually force it to skip steps - manually adjusting the bed height about 0.05mm up or down. I know what a good layer line looks like. Shouldn’t dig into bed. Shouldn’t be “round” Should be elliptical, with a flattened top. Should overlap with layer line printed next to it. Just grab the screw in the back, and turn it. It will resist you turning it, but eventually you will hear a click, and make it skip steps.

2. You turned off filament jam detection. And you are getting a filament jam - but only for like 2 or 3 layers. Then it starts making the result above. You would get a half finished print, followed by a birds nest. Try and look for it doing this. Turn on filament jam detection and try swapping to a new or different smart extruder. (you do have at least 3 smart extruders, right? You need at least 3. NEED. That is need in all caps, period at the end of the sentence. 2 is 1 and 1 is none.)

3. Something got changed. See first post. Reset everything. Level bed. Cant go wrong with that. Good first step.

4. you filament is wet. Water absorbs into a lot of plastics. It turns to steam in the hot end, and makes lots of little stringies. Result is little hairs on the finished print, but you do get a fully finished print. I don’t think this is what is happening here to you. Solution is to dry the PLA at 60 Celcuis for a bit and then store it in a dry box (see photography dry box), with desiccant, on a spool holder you will make out of a PVC pipe, and then drill a 4mm hole in the dry box and run a PTFE Bowden tube from the dry box, to makerbot.

[suecottingham]

I have found that if I can force the rafts to be on and the resolution to be at least 0.4 with supports on I can get some things that are recognizable. For instance see the pictures below. This is what I printed this morning for a student. I have included a picture of what was designed as well as how it turned out. As you can see. Part of it turned out…OK… part of it is not even close.

[suecottingham]

The extruder is set to 215c normally Makerbot told me to take it down to 210c so I have done that but it hasn’t seemed to help. When I load and unload I let the color go the whole way through and it produces an even flow so it seems to flow ok. Makerbot had me check all kinds of things. Some things on a plate print fine and some don’t - see the pics I just put up of the crocodile and the bird for mutualism. It is crazy.

[suecottingham]

I have found that if I delete the program off the computer and reinstall I can get one print every day (the school won’t let downloading for fear of viruses on their networks) so I have to take it home every day to do this. I do this with my laptop, my husband’s laptop, and the laptop for the printer. I try to get 3 prints per day. If one messes up, I am out of luck for that printer every day. Yes I am still in touch with Makerbot every chance I get. Level the plate after every print to make sure it is correct. I can’t find any functions other than the D in Tinkercad that lay things flat on the plate to reduce floating. I think that is me being new and EVERYONE has been so helpful! The students and I are learning TONS!

Thank you so much.

[suecottingham]

I have found that if I delete the program off the computer and reinstall I can get one print every day (the school won’t let downloading for fear of viruses on their networks) so I have to take it home every day to do this. I do this with my laptop, my husband’s laptop, and the laptop for the printer. I try to get 3 prints per day. If one messes up, I am out of luck for that printer every day. Yes I am still in touch with Makerbot every chance I get. Level the plate after every print to make sure it is correct. I can’t find any functions other than the D in Tinkercad that lay things flat on the plate to reduce floating. I think that is me being new and EVERYONE has been so helpful! The students and I are learning TONS!

Thank you so much.

[OZcardesign]

On the replicator 2 this kind of issue come from the engine wire, make some resherch on GOOGLE with “REPLICATOR WIRE ISSUE” maybe is the same one !

[DaveDelay]

Sometimes part tip over. Sometimes there’s bad adhesion. Sometimes I’ve even notices that makerware even goofs up and doesn’t get it right. I’d suggest to make sure the build plate is level by printing a one layer leveling file and inspect the bottom of the file to look for even pressure of the filament. For me and my 2X I always wipe the kapton build plate with iso alcohol every build for a clean surface.

[Andrew_Dowling]

Makerbot 5th gen is PLA only. I do agree with the possibility of a clogged nozzle.

[Andrew_Dowling]

I don’t think the re-installing the makerbot desktop is actually doing anything. I think you might be tricking yourself into thinking it is helping.

2 ideas here. I had a weird issue once where my screen stopped working. It was all white. I eventually found that if I left the makerbot unplugged for about 3 days, it would get better / go away. I think it was some sort of charge unbalance building up in the control board. But I honestly have no clue. Try unplugging you machine over a 3-4 day weekend (and maybe unplug it at the end of the day every day) and see if that helps.

#2, Also - print SLOWER, print hotter. Adjust your print speed to half what it is now. Under the custom menu - Adjust your temperature up to 216. Adjust all of the extrusion speeds down below 30mm /sec. First layer speed down to 10mm/sec. first layer of raft speed down to 10mm/sec. I think the gears that push the filament are having trouble keeping up with how fast the makerbot is trying to print. There might be something wrong with the smart extruder. I am trying to work you around the problem.

if the above doesn’t completely fix things, try adjusting the filament diameter down 0.1mm to 0.3mm.

Finally, add more shells under “model properties”. Try 3-4.

[magnacarte1133]

HOLD ON!

Let’s get the basics out of the way first before we make this instructor go way too far into places she doesn’t have a need to. She has to teach her students first, not research the hacks and tricks of the machine. And we don’t want her to screw any warranty protections she may have on the machine. Contact me through the hub and we’ll work this out together. Allow some time (not your lunch-break:)

Do not use modeling software to trick your 3d printers into behaving. There are tricks however, but that’s not going to help you in this case.

Cheers!

[Andrew_Dowling]

I wonder if this just comes down to the raft model spacing… Try bumping that down a bit. Too much and you might get a part that wont come off the raft, but if you get 100% good prints, its a step in the right direction. You might need to bump down the raft model spacing option for smaller prints. Been thinking about it all day, things I have experienced. Makerbot 5th gen is officially on my not recommended list in terms of reliability.

[suecottingham]

I use the painters tape that came with the printer - I clean it every 3-4 prints with alcohol but not every time. I will start doing that. That is an easy thing to do. Since this problem has started and Makerbot had me level the plate again, I have been leveling it before every print. The thing is sometimes it doesn’t print the bottom layer for it to adhere to and I think that is my major issue.

[suecottingham]

I only have the makerbot PLA filament from the makerbot site so that is a plus. When it does print it prints beautifully and it appears to be random when it decides to print and when it doesn’t. Some files will turn out just fine and others not.

[suecottingham]

I have tried to heat the extruder without the filament and it keeps telling me to load the filament. I am doing something wrong there. Test prints from the machine always come out right. I will keep trying.

Thank you for your help

[ch4s3r]

Hi Sue! I have been wondering what software are you actually using to print? Tinkercad or the makerbot slicer?

[3dworldhl]

Are you always printing with 0.4 mm layer height at least?

The max layer height recomended for a 0.4 nozzle is 0.36 mm. If the leyer height is higher the layers won’t stick well to each other.

The problem will be worse and much notable in models with smaller surface (as shown in the pict.).

Reduce the layer height to 0.15 mm (even if the prints take too much longer). If it solve the problem, increase gradually your layer height.

[Andrew_Dowling]

Don’t just math it out. Its not that simple. Things will work - there are other issues going on here. the smart extruder is far from perfect. there are a wide range of values that will work. 0,04 is not statistically significant!