Retraction Settings: How to Eliminate Stringing in 3D Printing
Stringing ruins otherwise perfect prints. This guide explains exactly how retraction works, the right values for every printer and filament type, and how to calibrate it precisely.
Stringing is one of the most frustrating 3D printing problems — fine hairs and threads connecting separate features, making your print look like a spider web. The fix is retraction, and this guide covers everything you need to know to dial it in perfectly.
What Is Retraction?
When your printer finishes printing one area and moves to another (a "travel move"), it can't just stop extruding — molten plastic will continue to ooze out of the nozzle. Retraction pulls the filament backward into the nozzle to relieve pressure and stop that ooze.
Retraction has two settings:
- Distance (mm): How far the filament is pulled back
- Speed (mm/s): How fast the filament is pulled back
Too little retraction = stringing. Too much retraction = jams, grinding, gaps, blobs when resuming.
The Critical Variable: Direct Drive vs Bowden
The type of extruder you have determines your entire retraction strategy.
Direct Drive Extruder
The extruder motor is mounted directly on the print head, right above the nozzle. The filament path is only 1–3cm.
Starting values:
| Setting | Value |
|---|---|
| Distance | 0.5–2 mm |
| Speed | 25–45 mm/s |
Because the path is short, you need very little retraction. Starting at 1mm is typical. More than 3mm on a direct drive often causes more problems than it solves.
Bowden Extruder
The extruder motor is on the frame, and a PTFE tube (often 40–60cm long) carries the filament to the print head. The long tube means you need more retraction to relieve pressure.
Starting values:
| Setting | Value |
|---|---|
| Distance | 4–7 mm |
| Speed | 40–60 mm/s |
The exact value depends on your tube length, tube fit, and filament. Worn PTFE tubes with gaps near the nozzle cause enormous stringing regardless of retraction settings.
Retraction Settings by Material
| Material | Direct Drive | Bowden | Notes |
|---|---|---|---|
| PLA | 1–2 mm | 4–6 mm | Most forgiving |
| PLA+ | 1–2 mm | 4–6 mm | Same as PLA |
| PETG | 0.5–1.5 mm | 3–5 mm | Reduce to avoid blobs |
| ABS | 1–2 mm | 4–6 mm | Increase temp first |
| ASA | 1–2 mm | 4–6 mm | Same as ABS |
| TPU | 0–1 mm | 0–2 mm | Often 0 is best |
| Nylon | 0.5–1 mm | 3–5 mm | Very sensitive to over-retraction |
How to Calibrate Retraction
Step 1: Print a Retraction Test
Download a retraction calibration print — typically two or more pillars separated by a gap. The print head travels between them with no extrusion, revealing exactly how much stringing occurs at your current settings.
Step 2: Establish a Baseline
Set your retraction to:
- 1mm (direct drive) or 5mm (Bowden)
- 40 mm/s speed
- Print at your normal temperature
Step 3: Adjust Distance
If you see stringing, increase distance by 0.5mm and reprint. If you see blobs or gaps where printing resumes, decrease distance by 0.5mm.
Continue until you find the minimum retraction that eliminates stringing without causing blobs.
Step 4: Adjust Speed
Once distance is dialed in, experiment with speed:
- Faster retraction speed generally reduces stringing but can cause grinding on flexible materials
- For PLA and PETG, 40–50 mm/s is a reliable target
- For TPU and Nylon, 20–30 mm/s or less
Other Settings That Affect Stringing
Combing / Avoid Crossing Perimeters
Routes travel moves through the interior of the print rather than over gaps. Enable this first — it's the easiest stringing fix and hides strings inside the model.
Travel Speed
Fast travel moves give the ooze less time to drip. Most slicers default to 150–200 mm/s for travel — make sure yours isn't set lower.
Temperature
This is the biggest lever after retraction. Every 5°C drop typically reduces stringing significantly. Print a temperature tower and lower your temperature if stringing persists.
Wipe Before Retract
Moves the nozzle in a short path while retracting, wiping excess plastic off the tip. Very effective for PETG.
Quick Reference
| Printer Type | Start Here |
|---|---|
| Bambu X1/P1 (direct drive) | 0.8mm @ 40mm/s |
| Prusa MK4 (direct drive) | 1mm @ 45mm/s |
| Ender 3 stock Bowden | 5mm @ 45mm/s |
| Ender 3 with direct drive upgrade | 1–1.5mm @ 40mm/s |
| Any Bowden, long tube (>400mm) | 6–7mm @ 50mm/s |
Find the verified retraction settings for your exact printer and filament in our Settings database.