How To Fix Brittle 3d Printer Filament? A Complete Guide

Do you have a 3d printer at home? Have you ever had the filament in your 3d printer break off into little pieces? How To Fix Brittle 3d Printer Filament?

This is one of the most common problems faced by people who are trying to use their 3D printers.

Luckily, there are ways to fix this problem so that it doesn’t happen again.

This article will show you how to fix brittle 3d printer filament so that you can get back to printing with no trouble!

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How to fix brittle 3d printer filament?

Ever had this happened?

You print something or your printer makes some noise and not much else; you go to inspect the printed part only to find it’s cracked. Broken. The dreaded BHET (Black Hole Exterior Trapped) filament syndrome is particularly common with PLA, but can obviously affect other materials like ABS as well.

The science behind BHET isn’t completely understood yet, but if you want to stop your stuff from breaking it’s best that we try to figure out what is going on at a fundamental level anyway.

The deformation process of brittle materials like PLA involves breaking large covalent bonds between atoms which are incredibly difficult to reform compared with the relatively weak Van der Waals forces associated with ductile materials like metals.

The problem with BHET is that it’s not always clear when exactly this process will occur, and worse still the process speeds up significantly as the material deforms even further (which gives it that nice clean snap we’re all looking for).

So what can we do about it?

Well, one thing we can try is to stop the material from deforming in such a way in the first place. A common misconception is that printing filament needs to be heated up to make it hard before extrusion.

Actually, you just need to keep print temperatures above room temperature (~20-25 degrees Celsius). We all know that hot melt glue sticks are really brittle until they’ve cooled down into that super stretchy phase, which means that if you cool down your filament too quickly you may also encourage BHET.

This is a really easy thing to test for, if the filament is cold after printing tries warming it up a bit and see what happens. It’s important that you use an accurate thermometer that can reach at least 60 degrees Celsius as PLA starts to degrade well below this value.

You want to keep your tests relatively short (a few seconds) to avoid excessive thermal gradients forming within the material. If you’re not getting any BHET then congratulations, all you need to do is tweak print temperatures accordingly!

How To Fix Brittle 3d Printer Filament? (Cre: 3dprinterly)

Now for those of you who are still having issues with BHET here’s something else for you to try! If we assume that our problem is caused by the deformation process (and that seems like a safe assumption), then we could try to slow this down.

One way to do this is to harness the power of friction, which has been known since before people were making chainsaws out of rocks and bits of flint. Friction will lead to more covalent bonds being broken at first but after these are completely broken it can actually help reform some of them on an atomic level which might just be enough to stop things from breaking. It’s also worth noting that adding some extra material around or even inside your printed object might also help prevent localized plastic bending where it isn’t wanted, which again should put the brakes on BH!

Baked Filament

So to finish up, let’s discuss something that is actually quite useful; filament baking. When you first extrude a filament the molecular structure of the raw plastic is really jumbled and no two ends of a melted strand will be perfectly aligned with one another (at least we hope they’re not…).

It follows then that if we heat up our filament enough we can partly align these molecules back into some kind of order which should make it much stronger!

In any case, there’s good evidence to suggest this does work so next time your print fails try putting the filament in an oven for a little bit at around 100 degrees Celsius, but don’t forget to leave it there for long enough as short periods may do nothing whatsoever!

And that’s it for this week brought to you by the letter B and number 6. As usual, I’m looking forward to what everyone else has to say so please leave your comments in the section below (or on our new google+ community). Until next time, happy printing!

How To Fix Brittle 3d Printer Filament? (Cre: rigid)

PETG breaking in the extruder, the First layer not sticking to build plate.

In my case, one of those issues was the reason for not printing anything further than the issue I had with this material. It is very frustrating to get out of bed in the morning and find out that you cannot print -while you were able to do it yesterday…

Well, what did happen?

To give some background information: I am using Prusa i3 MK2S 3D printer with E3D clone (our short review here ) hotend. For the filament, I usually order PLA/ABS rolls by 3Dnatives. Since started to offer also PETG, I decided to give it a try. So, the extruder broke down. At first, no filament was coming out at all.

I tried removing the filament several times and found that the filament is not getting extruded completely. My guess is that this has something to do with motor steps per mm calibration (which can be adjusted through LCD menus). Still, this did not fix the printing issue since PETG still would come out of the hotend without actually reaching the cold end where it could be caught by extruder gear/pinch wheel mechanism.

This must have damaged my stepper driver or pinion gear because eventually plastic started to build upon the other side of the cold end preventing any further movement of the extruder -a pretty similar situation like if you overload a 3D printer and it would not complete its move to the next point for printing.

Now, what I did:

1) Printed new cold end in PETG (which is working at the moment and still prints without any problems in PLA/ABS). You can find the STL file.

2) Since filament was still getting stuck somewhere inside hotend, I decided to remove the whole thing by using WD40 as a lubricant. This made things worse since all of the pieces got glued together because of that lubricant. I could separate parts but then pieces were just making bigger clumps due to rough surface after applying such “lubricant”. Now, maybe overkill but I started looking for a better way how to separate them apart.

3) Reading somewhere that acetone can be used to remove any sticks/glue, I decided to try it. This worked surprisingly well. I put a couple of drops of acetone on a bigger clump and started trying to separate pieces by hitting gently them against the desk (at first). Since parts were still connected together, this did not work very well so I applied more acetone and let the whole thing dry for about 20 minutes or so. After that, things came apart really quickly even though there were still several smaller clumps which just fell out pretty easily after a few gentle taps

4) Now all of the separated pieces but one were easy to handle since they still stuck together because their outer surface was covered with some kind of plastic-like coating. I repeated the acetone/dry procedure and got rid of that last little clump. This is how it looks like after everything was dry:

It seems that other parts are also stuck together but I am going to separate them with WD40 -which should work better since those parts were never glued together in the first place… So, what can you learn from this? If something does not look normal inside your hotend , do not hesitate to remove it from the extruder and check it out before trying some other tricks which might only make the situation worse 🙂

How To Fix Brittle 3d Printer Filament? (Cre: all3dp)

How to fix brittle PLA filament? by The 3D Printing Nerd

Most PLA (polylactic acid) filament that is sold off the shelf has problems when printing large prints for prolonged periods of time. This can be due to many reasons, among which are thermal stress induced by cooling down the print too fast after extrusion, lack of bed adhesion, and warping.

I’ve had some bad experiences myself with PLA not adhering properly to my BuildTak surface or to glass. When moving up in height from 220*220 mm to 250*250 I also noticed the layers were coming loose. Since I don’t use any glue or tape on top of my build task sheets, this was clearly an issue with either adhesion or shrinkage/warping.

When using ABS, PETG, or other more flexible filaments as part of your 3D prints you will not have this problem. This is because those organic materials are a lot softer and can follow the slight variations in height from one printed layer to the next. PLA on the other hand is a very brittle material that has a glass transition temperature of 60 degrees Celsius (I’m not going into the particulars of how these temperatures are measured). It means that if you cool down PLA too quickly after extrusion, this will lead to shrinkage and internal stress.

It’s not really apparent immediately when printing small objects with PLA, but I found out soon enough what happens when using larger layers (>200 mm) height.

The first thing that happened was that the top surface was lumpy and uneven, causing noticeable ridges.

This effect is caused by the shrinkage from cooling down from the molten state too quickly, which causes internal stress and will likely cause warping and possibly splitting in larger prints. This is what can happen:

I would like to claim this happens because I use a cheap filament supplier (DONT), but it’s actually pretty much any manufacturer of PLA filament you can buy at your local hardware or office supply store. Many brands do not even bother to test their products before selling them, thinking that it will not matter for small prints. What they don’t realize though is that just by slightly adjusting settings such as print speed and temperature they could get better results without investing any R&D dollars.

How To Fix Brittle 3d Printer Filament? (Cre: makershop)

After I switched to the Prusa PLA filament supplied with my i3 MK2, I have not had any problems whatsoever.

The prints are always nice and smooth, sticking well to both build task sheets as well as glass plates. No more warping or funky lumps on my top surface. When using an external print fan for faster cooling, this will also reduce the number of layers shifting causing less visible ridges in your 3D prints!

The Prusa branded PLA is manufactured by Eastman Chemical Company (more about that company here ). As far as I know, they don’t produce generic lines like Makerbot or Hatchbox (both brands used by many manufacturers) but seems that they’ve started selling their own line under the Prusa label.

There are probably other brands that do this as well, but I only tried the Prusa branded filament supplied with my i3 MK2 and can currently recommend it highly enough for all your PLA printing needs.

Conclusion

3D printing filament is a key component to every successful 3d printer. If you’re experiencing brittle, weak prints or if your extruder’s nozzle has clogged up with leftover filament that won’t feed through the tube, it may be time for some maintenance! We’ve created this guide on how to fix common issues like these and more.

When in doubt about what might be causing your problems, contact us – we’re happy to help troubleshoot any issue you encounter.

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Tags: #Petg #Tpu #Abs #Supports #Panels #Pause #Kidney #Lower #Speed #Creep #Quality #Adhesion #Monoprice #Filament #Firmware #Bed