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3D printer not extruding enough


How to Fix Under-Extrusion in 3D Printers – Not Extruding Enough – 3D Printerly

A problem that I’ve experienced with my 3D printer is an inconsistent extrusion from the nozzle with a print, which looks bumpy. I wondered how to fix this problem, so I researched exactly how to fix a 3D printer that stopped extruding consistently and got some answers that I’ll share with you.

The best way to fix a 3D printer that is extruding inconsistently from the nozzle is to clear any clogs or jams in the extrusion system, whether that’s in the extruder gears, Bowden tube or nozzle. You should also make sure your filament spool can rotate freely and use a larger layer height.

There are other factors that contribute to your 3D printing extruding inconsistently, which will be explained further in this article.

Why Does My 3D Printer Stop Extruding Consistently?

Bad Filament Pathing or Tangled Filament

If the filament is wounded improperly or the threads are not rolled off by the 3D printer correctly, the filament can get stuck resulting in uneven extrusion.

When the filament spool gets jammed, it produces friction which usually loses its grip on the material when fed into the printer. This results in lower emissions through the reduced flow of the material.

If the filament spool is empty, you will have to load the spool before moving forward. If the spool is not empty, you should check that the filament can easily pass through the Bowden tube.

Check to see if there is much resistance and consider cleaning the tube or applying some lubricant in the pipe.

Extruder Motor Issues

The extruder motor is the most functioning component of the 3D printer. It pushes and pulls the plastic back and forth constantly.

This fast motion requires a current, and if the printer’s electronic components are not cooled enough, the extruder motor will be overheated.

In this case, the motor controllers usually have a thermal cutout which causes the controller to stop working until the temperature goes down. So turn off the printer for some time allowing components to cool down.

Slipping of the Extruder Gears

If your extruder gears have start to wear out over time, it can’t get the same grip that it needs on the filament to extrude it through smoothly. I would check on your extruder gears and look for noticeable blunt areas on the teeth.

A good dual-geared extruder or a fresh extruder should correct this easily.

Layer Height Too Low

The layer height has a significant impact on 3D printing. If you are trying to print something at a low layer height, there will be very little room for the plastic to come out of the nozzle. Make sure to use the appropriate layer height for the printer.

You can change the layer height directly in your slicer software which has different methods depending on your program, but it should be fairly easy to operate.

Increase your layer height gradually through trial and error, and you should be able to eliminate the problem of not extruding during the print if this is your cause.

Inaccurate Extrusion Width

Like the layer height, extrusion width can also cause problems. Different extruders have different extrusion width, so be sure to choose the right extruder and assign the right extrusion width to get a silky and smooth 3D print.

It becomes difficult for the printer to extract material if the width of the extrusion is significantly less than the diameter of the nozzle.

According to the manufacturers, the perfect extrusion width is 100% to 150% of the diameter of the nozzle. You should be able to find these in your slicer using the search function, or by expanding the basic/advanced level view of your settings.

Extruder Jammed or Clogged

If the printer is not extruding enough, the extruder may be clogged. If this happens, check that the filament is clean and the spool is dust-free. If there is a lot of dust on the reel, it can block the extruder as it accumulates inside the nozzle.

In some cases, the plastic isn’t extruding properly, so you can try extruding some plastic manually. If you are still facing issues, you may need to clean the nozzle by following the instructions provided in the video below by Thomas Sanladerer.

Bad Quality Filament

A filament of inadequate quality is one of the most common reasons that cause printers not to extrude enough. Bad quality filaments contain some additives or have unstable filament diameters that affect the consistency of the flowing plastic.

The filament of high quality includes a dryer in the packaging because PLA absorbs the moisture from the air and affects the quality of the printer. If you think this is the problem, try replacing the existing spool with a new, sealed spool of better quality.

If your PLA has absorbed moisture and starts popping while being heated to high temperatures, some people have fixed this by placing it in an oven at a low heat. You can also use a food dehydrator to do the same job.

Heat Creep Issues

Heat creep is a form of a blockage or clog within your extruder system. It occurs because of a temperature imbalance, where the heat actually travels a little further than it’s supposed to into the PTFE tube.

What then happens is filament because softer within the filament tube and starts to get pushed around the outer extrusion path, leading to extrusion problems.

This can occur if your PTFE tube has worn out, or you have a bad heatsink which doesn’t negate heat away from this area.

How to Fix Inconsistent Extruding From Nozzle?

Patience is something that you will need to consider 3D printing as a profession or hobby. None of the solutions mentioned in this article is complicated. But you will need the patience to clean, remove, and fix the problem efficiently.

Once you find the cause of your inconsistent extrusion, the solutions becomes a lot easier to figure out as illustrated above.

The best intervention is to buy good quality filaments, make sure that the filaments and nozzles are clean, and review the best printer settings for your filament.

If you are experiencing under extrusion at a certain height, you want to check that your Bowden isn’t getting pinched at those higher heights. One thing you can do is to raise your Z-axis through the control box on your printer and see if there are any issues.

Installing a longer Bowden tube should fix this problem. The Creality Capricorn Bowden PTFE Tubing from Amazon is a good choice for your printer.

Increasing your printing temperature is another method that has worked for many users to fix under extrusion at a certain height, so I’d try raising your temperature to see if that helps.

You may be experiencing under extrusion after a nozzle change, retraction, on small parts or even at the start of a layer. There are fixes for each of these specific with the right knowledge.

One of the main reasons why you experience under extrusion after a nozzle change is due to not tightening your nozzle against the heatbreak. If you end up leaving a small gap, you can start to have melted filament slowly leak out of this area.

I’d also make sure to clean out your extruder gears of dust and debris. Also, make sure you don’t over tighten the gears on your extruder, and you want it to be tight enough to have a fairly good grip.

If you are getting under extrusion after retractions, I’d try increasing the retraction length as well as adding some “Retraction Extra Prime Amount” in Cura or your chosen slicer to 0.25 – 0.5mm. Increasing this setting means you add more pressure in the nozzle chamber after a retraction.

It can take a little bit of testing, since larger values can results in blobs on your prints.

Sometimes people get under extrusion on small parts which can be a pain. For one user, the cause was through a badly wound spool of filament that was twisting and causing strong resistance in the Bowden tube. I’d check for the filament pathway and make sure things are going through smoothly.

In some cases, you may just have to change your nozzle to a fresh one, especially if you have never changed your nozzle and you use a brass one. With standard filament, brass nozzles can hold up pretty well, but after a few hundred hours of printing, or from scraping on the build plate, a change can be in order.

If you are getting under extrusion at the start of a layer, check that your “Retract at Layer Change” setting is unchecked as this can decrease the pressure in the nozzle chamber. I’d also try increasing your “Retraction Extra Prime Amount” to a value around 0. 5 – 0.8mm.

Another solution for this issue that has worked for many users is to try turning “Combing Mode” off in Cura or your slicer.

How Can You Tell if a Nozzle is Clogged?

The most obvious symptom is that the filament does not come out of the nozzle properly. The filament is curling or sticking to the tip of the nozzle. There will be a sound or clicking from the extruder. The other signs include:

  • The extrusion is looking inconsistent.
  • A lot of dust around the extruder motor.
  • The print is not silky or smooth.
  • Dotted lines around the print.
  • The printed parts are too fragile.
  • The filament spool has stopped turning.

How Do You Fix a Clogged Nozzle?

When you have a clogged print nozzle, you can use a number of cleaning techniques to resolve the issue depending on the material that is causing the hassle.

The method always recommended by the experts is to use cleaning filaments regularly, but this method is only suitable for partially clogged nozzles and will not open the completely clogged issue. Below are some other techniques to fix a clogged nozzle.

  • Use a brass wire brush to clean the dirt from the nozzle.
  • Acetone is well known to dissolve thermoplastic. Cleaning the nozzle with an acetone bath helps to remove unwanted particles and will fix the clogged nozzle.
  • The other way to fix a clogged nozzle of 3D Printer is to clear it using an acupuncture needle.
  • Heat the nozzle to 250 degrees Celsius and insert the cleaning filament into the nozzle until the nozzle is completely free of old threads. Remove the filament and reheat the nozzle to remove tiny filament particles and then clean the nozzle thoroughly.

It’s usually easy to distinguish under extrusion vs over extrusion for your 3D printer. You’ll see that your 3D prints have more gaps and are generally weaker than usual if you have under extrusion.

Over extrusion is also clear to see, where you have plastic squashed together, leading to a low quality 3D print that isn’t very dimensionally accurate. It is most visible in the outer dimensions of your 3D print.

How To Clean & Prevent 3D Printer Jams

There are various solutions to fix 3D printer jams, but the ideal solution is to prevent it from clogging. Below are the tips that will help you to clean and deter 3D printer jams in the future.

Thoroughly clean the nozzle when switching between filaments.

  • Print at the right temperature to avoid electronic components overheat
  • Use a clean filament of high quality
  • Calibrate your printer bed at the right level
  • Set an optimal and perfect layer height of 50% to 70% of the nozzle height, which is recommended by the experts.
  • Try to store your spool in an airtight bag because this will not only prevent dust from accumulating but also prevents the absorption of the moisture from the air.

Not Extruding at Start of Print

Not Extruding at Start of Print

This issue is a very common one for new 3D printer owners, but thankfully, it is also very easy to resolve! If your extruder is not extruding plastic at the beginning of your print, there are four possible causes. We will walk through each one below and explain what settings can be used to solve the problem.

Common Solutions

Extruder was not primed before beginning the print

Most extruders have a bad habit of leaking plastic when they are sitting idle at a high temperature. The hot plastic inside the nozzle tends to ooze out of the tip, which creates a void inside the nozzle where the plastic has drained out. This idle oozing can occur at the beginning of a print when you are first preheating your extruder, and also at the end of the print while the extruder is slowly cooling. If your extruder has lost some plastic due to oozing, the next time you try to extrude, it is likely that it will take a few seconds before plastic starts to come out of the nozzle again. If you are trying to start a print after you nozzle has been oozing, you may notice the same delayed extrusion. To solve this issue, make sure that you prime your extruder right before beginning a print so that the nozzle is full of plastic and ready to extrude. A common way to do this in Simplify3D is by including something called a skirt. The skirt will draw a circle around your part, and in the process, it will prime the extruder with plastic. If you need extra priming, you can increase the number of skirt outlines on the Additions tab in Simplify3D. Some users may also prefer to manually extrude filament from their printer using the Jog Controls in Simplify3D’s Machine Control Panel prior to beginning the print.

Nozzle starts too close to the bed

If the nozzle is too close to the build table surface, there will not be enough room for plastic to come out of the extruder. The hole in the top of the nozzle is essentially blocked so that no plastic can escape. An easy way to recognize this issue is if the print does not extrude plastic for the first layer or two, but begins to extrude normally around the 3rd or 4th layers as the bed continues to lower along the Z-axis. To solve this problem, you can use the very handy G-Code offsets which can be found on the G-Code tab of Simplify3D’s process settings. This allows you to make very fine adjustments to the Z-axis position without needing to change the hardware. For example, if you enter a value of 0.05mm for the Z-axis G-Code offset, this will move the nozzle 0.05mm further away from the print bed. Keep increasing this value by small increments until there is enough room between the nozzle and the build platform for the plastic to escape.

The filament has stripped against the drive gear

Most 3D printers use a small gear to push the filament back and forth. The teeth on this gear bite into the filament and allow it to accurately control the position of the filament. However, if you notice lots of plastic shavings or it looks like there is a section missing from your filament, then it’s possible that the drive gear has removed too much plastic. Once this happens, the drive gear won’t have anything left to grab onto when it tries to move the filament back and forth. Please see the Grinding Filament section for instructions on how to fix this issue.

The extruder is clogged

If none of the above suggestions are able to resolve the issue, then it is likely that your extruder is clogged. This can happen if foreign debris is trapped inside the nozzle, when hot plastic sits inside the extruder too long, or if the thermal cooling for the extruder is not sufficient and the filament begins to soften outside of the desired melt zone. Fixing a clogged extruder may require disassembling the extruder, so please contact your printer manufacturer before you proceed. We have had great success using the “E” string on a guitar to unclog extruders by feeding it into the nozzle tip, however, your manufacturer should also be able to provide recommendations.

Related Topics

Problems, defects, 3D printing errors and solutions

Often during the operation of a 3D printer, problems may arise due to which defects appear on the finished model. Or instead of a neat product, plastic noodles suddenly appear on the table.

In fact, the causes of defects can be conditionally divided into 2 types - these are physical and software.

Physical ones are those that arise due to problems with the mechanics or any other causes that can be eliminated physically. These include problems with printer mechanisms (belt tension, backlash), clogged or deformed nozzle, incorrect table geometry, etc. nine0003

Software - these are defects that occur due to incorrect slicer settings or, less often, errors in the printer firmware. For example, incorrectly selected print speed, retract settings, incorrectly selected temperature for plastic, etc.

Very rarely, the problem may lie in the wrong or “flying” printer firmware (although usually the printer simply will not start then), overheating of some boards during printing, etc. These are rather special cases, so we will not consider them. nine0003

Model peels off or does not stick to the build plate

This is the most common 3D printing problem. Every 3D printer has had a case when the first layer treacherously rolls, clinging to the extruder, or the most offensive - when it tears off a partially printed model from the table. The first layer must stick tightly otherwise nothing will be printed.


Gap between table and nozzle 9 too large0023

This is the most common reason. You just need to set the correct gap between the table and the nozzle.

Modern printers often use an auto-calibration (auto-leveling) table system or an auxiliary table leveling program. To calibrate such printers, use the instructions. If there is no manual, it can be downloaded from the manufacturer's website.

If you have a simple printer without auto-calibration, a self-assembly or KIT kit, use a probe or a piece of paper folded in half to calibrate. The probe should be slightly pressed against the table by the nozzle. Before calibration, the table and extruder must be heated. Align the table surface over each adjustment screw (there may be 3 or 4) in turn, and only then check the center point. nine0003

If you're having trouble getting your table surface perfectly level, try raft printing. Raft is a thick substrate in several layers that is printed under the model. It will help smooth out the slight curvature of the table.


A small cheat sheet to determine the correct gap on the first layer

Plastic with poor adhesion

Some types of plastic, due to various reasons, such as large shrinkage, do not adhere well to the surface of the printing platform. In this case, try using stickers or special 3D adhesives to improve adhesion between the table and the first layer of plastic. nine0003

In the early days of 3D printing, there were experiments with different homemade 3D adhesive recipes. ABS diluted in acetone, BF glue, sugar syrup and even beer. Some experiments have been successful. Until now, some enthusiasts use some types of hairspray or glue sticks as 3D glue. But still they are inferior in their properties to industrial 3D adhesives.

Some types of high temperature plastics with a high percentage of shrinkage (ABS, Nylon, etc.) may peel off the table during printing. This is due to uneven cooling and “compression” of the model (the lower layers have already cooled down, but the upper ones have not yet). For such plastics, it is imperative to use a 3D printer with a heated table and a closed case. nine0003

Plastic temperature too low

The hotter the plastic is when it exits the nozzle, the better it will adhere to the print bed. It is better to print the first 5-10 layers at a higher temperature (+ 5-10 degrees) and turn off the blower fan.

Wrong first layer settings (speed and thickness)

A thicker layer sticks easier, so the standard first layer is 0.3mm thick. With an increase in print speed, the heating block may simply not have time to heat the plastic to the desired temperature and it will stick to the table worse. Before printing, check the speed and thickness settings of the first layer in the slicer. nine0003

A lot depends on how the 3D printer prints the first layer. Try to control the printing of the first layer and only then leave the printer to work alone.

Plastic does not choke from nozzle

The printer has already begun to print, but the print table remains empty. Or part of the model did not print.


Clogged nozzle

In 3D printing, a nozzle is a consumable. The nozzles are clogged or worn out (frequency depends on the type of plastic). The simplest thing is to replace the nozzle. But if there was no spare at hand, you can try to clean the old one. To do this, there is a whole set of thin needles. Or you can heat a clogged nozzle above the melting point of the plastic and “burn out” the blockage. But later it is still better to replace the nozzle. nine0003

Low temperature nozzle

You need to increase the temperature of the extruder in the slicer settings or check the thermistor and heating block. Sometimes the thermistor may not read the temperature correctly due to a malfunction or incorrect 3D printer firmware settings.

If the problem occurs after replacing the thermistor - contact the manufacturer or read articles about PID tuning.

Empty extruder

As the extruder heats up, plastic begins to ooze out of the nozzle. Because of this, the extruder may start printing half empty. Because of this, part of the first layer is not printed. You can push the plastic manually by simply pushing the bar into the nozzle. Or solve this problem programmatically - in the slicer, add a contour print around the model (one line).

Some manufacturers and 3D enthusiasts add a line print on the edge of the table at the beginning of each GCode. This is done so that there is plastic in the nozzle by the time the model is printed. nine0003

Feed mechanism does not push through plastic

The plastic pushes the feed mechanism to the extruder - a motor with a special pulley put on the shaft. If for some reason the plastic is not pushed through (nozzle clogged, extruder temperature low, etc.), then the pulley “gnaws” through the bar. You need to push the plastic bar with your hands or cut off the damaged piece.


Elephant foot

The first layers of the model are wider and protrude beyond the boundaries of the model. This is due to the fact that the upper layers put pressure on the first ones that have not yet cooled down and flatten them. nine0003


High table temperature

Due to the too high temperature of the table, the lower layers remain soft for a long time. Try lowering the table temperature. It is better to reduce gradually (in increments of 5 degrees). You can try to turn on the blower when printing the first layers.

Small gap between nozzle and platen

If, when printing the first layer, the nozzle is too close to the table, then excess plastic will be forced out. After a few coats, this will not be as noticeable, but can lead to the effect of an “elephant's foot”. nine0003

Plastic re-extrusion

When too much material is squeezed out of the nozzle, the walls of the model are not smooth, but bumpy, with sagging.


The solution is software - in the settings of the slicer, you need to set the material feed rate (fluidity) to a lower value. The average value is 95-98%.

It is worth checking the diameter of the rod. If its size is greater than 1.75, then the plastic will be squeezed out more than necessary. nine0003

Plastic underextrusion

The plastic is squeezed out too little, because of this, gaps may appear between the layer. The finished model will be fragile and fragile.


Wrong thread diameter

Check the filament diameter in the slicer settings. Sometimes, instead of the popular 1.75, the default is 2.85.

Incorrect feed factor settings nine0003

Check the fluidity settings in the slicer. The average should be 95-98%.

Clogged nozzle

Something could get into the nozzle and partially block the exit of the plastic. Visually, the plastic will choke from the nozzle, but in a smaller amount than necessary for printing.



Hairiness or cobwebs on finished model

Thin threads of plastic protrude from the outer wall of the model (most often on one side). The defect appears due to the flow of plastic from the nozzle during idle movement. nine0003


Insufficient retract

A retract is a slight pull of a plastic filament from an extruder. Due to the retract when the extruder is idle (from layer to layer or from model to model), heated plastic does not drip from the nozzle. For some flowable plastics (eg PETG) the speed and amount of retraction must be increased.

"Hairiness" can be easily removed by grinding or cutting off the threads with a sharp scalpel. nine0003

High temperature extruder

The higher the extruder temperature, the more fluid the plastic becomes. It is important to find a balance so that the plastic is not too liquid and sticks well in layers.

In the selection of the optimal extruder temperature, a test model - a tower - helps a lot. It clearly shows how plastic behaves when printed at different temperatures.

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Temperature test nine0003

Top "perforated" or uneven

The top of the model is bumpy or with holes. The problem may arise if the top of the model is flat. For example, like a cube.


Insufficient airflow

When printing the top plane (cover), the plastic does not have time to cool down and remains too liquid. Because of this, the threads are torn and holes are formed. Increase the fan speed on the last layers. nine0003

Few top layers

The top of the print may be too thin and deform as a result. Check slicer settings. The number of upper layers is not recommended to be set less than 6.

Low percentage of filling

If the infill percentage is too low, then the top layer will simply have nothing to rely on. Increase the fill percentage in the slicer settings.

Model deformation

Some parts of the model seem to have melted in some places or on one side. The problem most often occurs when printing with PLA plastic. The defect appears due to the fact that the plastic does not have time to cool and deforms.


Insufficient airflow model

Turn the fans on to maximum. If their power is not enough (in some printers, the fan is located only on one side), you can put a regular desktop fan and direct it to the 3D printer table. nine0003

Small model

Small models are difficult to blow well. Try to print small items alongside larger ones, or place several identical models in different corners of the table. So the plastic will have more time to cool.

Layer offset

Layers shift along the x or y axis during printing.


Print head jam

Turn off the printer and try to move the extruder along the x and y axes with your hands. The extruder must move freely. If there are jams, check the mechanics of the printer. Bearing wear or the curvature of the shafts may be to blame. nine0003

Electronics overheating

Sometimes electronics problems can be to blame for misaligned layers. The most common cause is overheating of the drivers or too low current exposed to them.

Table top is loose

This is most often seen in 3D printers with glass. During printing, the nozzle may hit the model and move the glass slightly. Before printing, check if the glass or other printing surface is well fixed on the heating table. nine0003

Skip layers

Small holes are visible on the print, or the shell of the model is not continuous.


Teflon tube deformed

There are 2 types of thermal barriers - all-metal and with a Teflon tube. If overheated, the Teflon tube may deform. Plastic will pass through it, but in a smaller amount.

Low extruder temperature or high print speed

If the extruder is not heated enough, then the plastic will not be liquid enough and simply will not have time to be forced through the nozzle. The higher the print speed, the higher the extruder temperature should be.

Sometimes the outer walls print well, but the infill is “torn”. In this case, slow down the infill print speed in the slicer.

Model bundle

Cracks form on the surface of the printout during or after printing. Cracks can be large or very small. Most often, this problem occurs with plastics with a high percentage of shrinkage - ABS or Nylon. nine0003


Sudden temperature difference (if model delaminates during printing)

With a sharp temperature difference (for example, a draft), part of the model cools down faster. This leads to uneven shrinkage and incorrect distribution of internal stress. For plastics with low shrinkage, this is not critical. But if the shrinkage percentage is more than a few percent, the model may burst in layers.

For printing with such plastics, it is recommended to use a printer with a closed housing. If this is not possible, try to avoid drafts and sudden temperature changes in the room where the 3D printer prints as much as possible. nine0003

Print temperature

Due to too low printing temperatures, the layers may not “stick” well to each other. Raise the print temperature in the slicer settings.

Hardening (if the model cracks after printing)

Sometimes cracks appear on the model a few days after printing. This is due to uneven distribution of internal stress after cooling. You can try to “harden” the finished product. nine0003

For hardening, the model is placed, for example, in an oven, and heated to the softening temperature of the plastic. After that, the heating is turned off and the oven is left to cool slowly with the model inside. Due to this, the stress inside the print is distributed more evenly. But accuracy is very important in this method - if you make a little mistake with the temperature, the finished product can “float”.

Ringing

In places where the extruder changed direction, ripples are visible. Most often it looks like a shadow around the “sharp” protruding elements of the model. nine0003


Mechanical problems

Sometimes the problem occurs due to extruder play. Check if the extruder mount to the rails is loose. Be sure to check the tension of all belts.

High print speed or high accelerations

Moving the extruder too fast can cause vibrations that cause ripples on the wall of the model. The lighter the weight of the extruder, the less noticeable the ripples will be. To get rid of ringing, simply reduce the print speed in the slicer settings. nine0003

Slits for thin-walled models (not solid shell)

The thin wall of the model is not solid, but consists of two thin walls with a narrow gap between them. This problem is often faced by fans of printing "cutting" for baking.

Left model with wall defect, right without

Wall thickness and nozzle diameter mismatch

If the wall thickness is 1 mm, and the nozzle diameter is 0.4, it turns out that for a solid wall, 2 nozzle passes are few, and 3 are already many. The result will depend on the slicer algorithm, but most often you will get 2 walls with a thin slot in the middle (the slicer cannot change the wall thickness). The solution to the problem may be a slight refinement of the 3D model or the use of a different slicer. nine0003

Algorithms for calculating 3D models are constantly being improved and refined, and now this problem is less common.


When modeling, take into account not only the thickness of the nozzle, but also the percentage of “overlapping” of lines on each other. If you have a nozzle with a diameter of 0.4 - make the wall in your model not 0.8, but 0.7 - 0.75.

Wrong model geometry

When instead of a circle you get an oval, and instead of a square you get a semblance of a rhombus. nine0003


The main reason is malfunctions in the mechanics of the printer. Be sure to check:

Belts

Check belt tension in x and y. Belts stretch over time and may need to be tightened or replaced. Each 3D printer has its own way of tightening the belt. If the belts are slightly stretched, you can tighten them with the help of a "spring".

Loose pulleys, etc.

Check if all bolts and nuts are tight. Are there backlashes. Pay special attention to tightening the pulleys located on the motors along the x and y axes.


Sagging of some parts of the model

Some parts are not printed, broken, or instead of a neat surface, a swollen plastic snot is obtained.


No support for overhangs

A 3D printer cannot print in the air, so if there are overhanging elements in the model, you need to set supports - supports. The slicer can set the necessary support itself, you need to check the appropriate box in the settings. nine0003


When printing with soluble support, you can set the gap between the model and support - 0. This will make the surface smoother. If the support material and the model are the same, you need to add a small gap. Otherwise, it will be difficult to separate the support from the model.

Split model

Sometimes the supports can take more plastic than the model. In this case, to save material and time, it will be more convenient to cut the model. If you have more than one 3D printer, then the model will print several times faster. nine0003

When cutting the model, you can leave grooves or mortgages so that the pieces of the model are connected without displacement.


Totals

In this article, we talked about the most popular 3D printing defects and how to solve them. Don't be intimidated by such a long list. Some problems are rare and you are unlikely to encounter them.

There is a list of problems that arise due to the design features of a 3D printer, so try to choose a printer that suits your needs. To do this, you need to understand what products and what material you need. nine0003

Problems associated with printing algorithms are quickly eliminated by software developers.

Do not be afraid of possible difficulties and each seal will be successful.


3D printer does not feed plastic from the nozzle when printing.

Recently, 3D printers are beginning to gain popularity, and this is not surprising, because 3D printing allows you to create almost any shape, and the printers themselves are starting to drop in price, as a result of which they become more affordable. It would seem that it is enough to buy a printer, but after buying a printer comes the understanding that printing is not as easy as it seems, and setting up and calibrating the printer can take a lot of time, from several hours to several days, or even weeks. nine0003

In this article I want to tell you how to solve one of the most annoying problems that you will surely encounter with any 3D printer - when the plastic does not feed when printing or it feeds in pieces.

I will give an example from personal experience. Not so long ago, about a couple of months ago, I purchased my first Anycubic i3 Mega 3d printer, it took me a week to calibrate the printer and study the basic parameters for printing, after which I printed various shapes for a long time without problems on PLA plastic, which went to kit. And so, when the PLA plastic ended, I decided to buy myself ABS plastic for a test to see what the difference was from PLA. I inserted ABS plastic, printed the first figure, and when I started printing the second figure, I got the same result as in the photo - the plastic did not stick to the table, it was squeezed out of the nozzle in pieces, printed lines through one, and eventually stopped printing altogether:

My first suspicions fell on the nozzle (photo), which was eventually confirmed - the nozzle clogged when mixing ABS plastic with the remnants of PLA plastic, which burned into the nozzle.

The solution to the problem was simple: take pliers, clamp the nozzle, take a burner and burn the plastic out of the nozzle for about five minutes. If you want the nozzle to return to its original shiny appearance, then we throw it into a bowl of boiling water and vinegar / citric acid.

A day after cleaning the nozzle, problem No. 2 appeared - the plastic again stopped “going” from the nozzle. I started cleaning the nozzle again, but it didn’t help, by the way, the plastic began to grind against the gear of the stepper motor (the stepper motor could not push the plastic thread into the extruder, as if something was in the way), in the end it turned out that the plastic was clogged / burned in the thermal barrier due to the fact that the sealing tube was not inserted to the end of the thermal barrier, the thermal barrier itself heated up and melted the ABS plastic, creating a “plug”:

Plug:

The solution to the problem is the same as with the nozzle - we disassemble the extruder, “pull out” the plastic with a burner, push the sealing tube to the very end, assemble the extruder, enjoy printing.

Below is a photo of the extruder, in the photo the upper part is a thermal barrier (it must be cooled), the lowest golden part is a nozzle, between the thermal barrier and the nozzle is a heating element that melts plastic.

Below I want to give additional ways to solve the problem when plastic does not come out of the nozzle, let's look at them. nine0003

1. Choose a plastic recommended by the printer manufacturer

Each type of plastic differs not only in color, but also in a number of properties - material, diameter, melting point, so we look at the characteristics of the printer, which plastic can be used. Example: you bought plastic with a diameter of 2.85, and your printer has a sealing tube with a diameter of 1.75, the plastic will simply get stuck in the tube.

2. The plastic has run out or the plastic is tangled in the spool

If you have chosen the right plastic, but printing still does not work, look at the spool, the plastic may have already run out or is tangled. nine0003

3. Plastic has worn off on the gear of the stepper motor or a problem with the clamping mechanism

We look at the stepper motor that feeds the plastic into the extruder, if the gear is spinning and the plastic does not go, then there may be 5 problems:

- Extruder clogged, see item 4.

- Slow feed has chipped plastic on gear. We take out the “broken off” plastic from the sealing tube, insert a new plastic.

- The clamping mechanism has broken. Usually it consists of a spring and a roller, we look, maybe the spring has moved away. nine0003

- If you changed the stepper motor drivers, then the motor may not have enough power to push through the plastic.

- Stepper motor failure. We check by replacing the engine from some axis.

4. Extruder clogged

Above, I described what the extruder consists of (thermal barrier, heating element, nozzle). If the extruder is clogged, then you need to understand in which of its parts, for this we disassemble the extruder completely and see where the plastic is, burn it out with a burner. nine0003

If the plastic enters the extruder and the extruder is not clogged, check the wires on the heating element and the heating element itself, it is possible that the contacts are faulty due to which there is no heating, due to which the plastic is not delivered.

5. Insufficient temperature for heating plastic

If everything is OK with the previous points, check the heating temperature for plastic in the print settings. Each type of plastic has certain properties, one of them is the melting point. If the temperature is very low, the plastic will not melt and will not come out of the nozzle, and vice versa, if the temperature is too high, the plastic may burn and clog the nozzle. nine0003

An example of temperatures for the two most popular plastics:

PLA - heating temperature 180 degrees, table heating temperature 60-80 degrees

ABS - heating temperature 240 degrees, table heating temperature 110 degrees

6. Nozzle pressed too hard against the table

If the table is not calibrated and the nozzle is strongly pressed against it, then the plastic will not flow, you need to calibrate the current table so that there is a gap between the table and the nozzle of 0.

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