Overlocker Not Cutting Fabric or Cutting Unevenly - How to Fix It
If your overlocker has stopped trimming the fabric edge cleanly, or isn't cutting at all, it's usually one of three things - the knife is disengaged, the blade is blunt, or the blade needs replacing. Here's how to work through it.
Work through these steps in order
Start at step 1 and work your way down - most cutting problems have a simple cause.
Check the knife is engaged
This is the most common cause of the machine not cutting at all. It's very easy to accidentally disengage the knife, particularly if you've previously been doing a flatlock or another technique that requires it to be switched off.
- Check the knife engagement lever or switch is in the correct position for cutting
- Refer to your manual if you're unsure where this is on your specific model
Check the blade condition
Overlockers have two blades - an upper and a lower. Understanding which one is likely to be the problem saves time.
- If the cut edge looks ragged, torn or uneven rather than clean, the blade is likely blunt and needs replacing
- The upper blade does most of the cutting work and is the one that needs replacing most often - start here
- The lower blade is more durable but can be damaged if you've sewn over a pin - if replacing the upper blade doesn't fix the problem, inspect the lower blade for nicks or damage
- General wear on the lower blade over time can also affect cutting quality even without a specific incident - if you sew regularly and haven't changed it in a long time, it may be due
Replace the blade
Blade replacement is straightforward but needs to be done carefully - the knife is extremely sharp.
- Turn the machine off completely before attempting to replace the blade
- Follow your manual carefully - upper and lower blade replacement procedures differ and vary between models
- Never touch the blade edge with your fingers
- Dispose of the old blade safely - wrap it in card or tape before putting it in the bin
Check the cutting width
If the machine is cutting but trimming too much or too little fabric from the edge, the cutting width may need adjusting.
- Locate the cutting width dial or setting on your machine - check your manual if unsure
- Adjust and test on scrap fabric until the trim width looks right for your project
Check for fabric that's too thick
Very thick fabrics or too many layers at once can be too much for the blade to cut through cleanly, even when everything else is set up correctly.
- Try reducing the number of layers if possible
- Slow right down when approaching thick seams to give the blade time to cut through cleanly
- If you regularly overlock heavy fabrics, check your machine's specifications to confirm the maximum fabric weight it's designed to handle
Test on scrap fabric
Before returning to your project, test on scrap fabric of a similar weight. Check the cut edge is clean and even along the full length of the seam before continuing with your actual work.
Quick fix checklist
Run through this before contacting us - it covers the most common causes.
- Knife engagement lever checked and confirmed in the cutting position
- Upper blade inspected for wear and replaced if blunt or damaged
- Lower blade inspected for nicks or damage, especially if a pin has been sewn over
- Blade replaced with machine turned off and manual followed carefully
- Cutting width checked and adjusted if trimming too much or too little
- Speed reduced for thick fabrics or multiple layers
Still having trouble? We're here to help.
If the overlocker still isn't cutting cleanly after working through these steps, get in touch and our team will take it from there. We stock replacement blades for most overlocker models.
Still stuck? We are happy to help.
Our service team has seen every machine in our range and can usually diagnose problems over the phone.
