In this quick guide, let's discuss how to prevent 3D printer oozing before starting a large print project to eliminate frustrations, and to create successful prints.
We are going to cover root causes and solutions to fix the problem.
Let's get started
Root Causes
- Overextrusion is the number 1 cause of oozing due to excessive filament coming out of the nozzle.
- Poor retraction setting
- Uncalibrated printing speed
- Uncalibrated printing temperature
- Clogged nozzle
Try These Solutions
Clean Hot End
Disassemble the hot end and thoroughly clean the nozzle if the 3D printer stops mid-print via the Atomic pull method.
Other times, a clogged extruder nozzle happens when the temperature isn’t hot enough to keep the filament soften enough and feed through the nozzle.
- Use a brush with metal wires to clean the nozzle
- Always clean the nozzle when switching to another material
- Clean right after a print to maintain the hot end
- Always keep dirt particles and material residue away from the nozzle
Clean it first! Do not try printing again until it’s fixed.
Other times, a complete nozzle replacement is needed after frequent use.
Re-Dial Printing Speed
Check the speed tab on your 3D printer and lower the print speed to see if that fixes the problem. Print speed plays a major role in print quality, and the time it takes your extruder to move and the amount of filament coming out of the nozzle has to be relatively calibrated, so the filament has enough time to exit the nozzle.
- Try 40 - 60 mm/s first then fine tune the speed to mitigate filament leaks and stringing
- Try 150 - 200 mm/s travel speed
- Try a small test project first
Typically, when the extruder is moving to a new location, the filament cable is pushed back into the nozzle so it can be extruded from the tip again.
Try different speed settings to find the sweet spot.
Adjust Retraction Distance & Speed
Retraction speed matters a lot in terms of reducing oozing and stringing. Here are a few settings to pay attention to when adjusting:
Retraction distance ( - The long er the distance is the more time it takes to retract relative to the speed - Less stringing
Retraction speed is very important that influences print time as well as reducing stringing and oozing. If the sweet spot is 5 mm distance with a speed of 40 mm/s, you may experience a different result when it's 5 mm and 20 mm/s.
Slow speed doesn't relieve the pressure fast enough to prevent excessive extrusion.
When dialing the speed, try 5 mm/s increments until no visible problems occur. A good retraction starts at 50 mm/s with a distance of 3 mm.
Adjust Temperature
Reducing the temperature helps extrude less heated (Liquid form) material, which reduces stringing and oozing. Higher temperature materials are more prone to stringing due to their viscosity properties.
- Lower temperature and monitor if there are any improvements
- Perform a small test project before committing to a large print project
- Use higher temperature for a good first layer adhesion, then lower the temperature for the rest of the print
- Try different materials and find the temperature sweet spot for every one of them
- Lower extrusion speed so the timing of filament material melting and extruder movements are closely coordinated
- Use PLA (Can also string and ooze if not used properly)
Fine Tune Extrusion Amount
Calibrate the material extruder to make sure only an appropriate amount of filament is extruded. We can do this by fine tunning the E steps and measuring them.
Repeat the process until getting it right. Avoid over extrusion at all cost.
Adjust Extrusion Line Width
Always match the nozzle diameter with the width of the line to improve the print result.
Match Filament Nozzle Diameter To Filament
Always match the filament diameter to the diameter of the nozzle. 1.75mm or 2.85mm are the two most common filament diameters on the market.
Check Filament Flow Rate
Make sure flow rate is 100%
Maintain Proper Filament Storage
Always store the filament spool airtight container in a dry environment to prevent absorbing moisture.
Moisture is a bad thing for 3D printer filament. We call it hygroscopic, and the moisture is transformed into steam in the nozzle resulting in pressure reduction leading to filament dripping out of the nozzle.
