Annual service is critical to getting the maximum machine life and optimal sewing experience from your machine. Bernina machines are made with stitch precision in mind and just like any piece of fine machinery, it requires routine maintenance and service. Do you change the oil, brakes, wiper blades, tires and alignment on your car on a regular basis? I hope so. Even though cleaning and lubrication is a critical part of annual service, it also includes much, much more. Here’s a typical list of procedures that Quilt Perfect performs when providing service for your machine.
- Ground the Machine Properly:
First, the technician places the machine on an anti-static mat and attaches an anti-static wristband to themselves. This step prevents any electrostatic discharge by safely grounding them while they work on the machine, protecting the delicate electronics inside. - Diagnostic mode:
Access the internal memory to determine if the machine has experienced or diagnosed any issues. - Expose the Key Components:
Next, the technician removes all covers to gain access to the major components of the machine. Full exposure is necessary to ensure nothing is missed during the inspection. - Electronics
Inspect all cables and boards for proper connection, damage or wear. - Clean Thoroughly:
All lint, dust, broken needles, pins, etc., and old oil are carefully removed from the machine. A clean machine runs smoother and lasts longer—no room for debris that could cause unnecessary wear. - Untangle the Threads:
Any thread wrapped around the hand wheel, bobbin winder, take-up lever is cleared away. These seemingly small tangles can create bigger problems and even create tension issues. - Clear the Tension Discs:
The technician checks and clears the complete thread path including the top tension discs for any lint build-up, especially from low-quality threads. Cleaning these discs ensures smooth thread flow and consistent tension. - Inspect the Belts:
Both the timing and motor belts are inspected for proper tightness and wear. A loose or worn belt can drastically impact the machine’s performance. - Check the Motor Brushes:
In older machines, the technician inspects the motor brushes and ensures the motor turns freely. Any resistance or wear can affect the machine’s power and speed. - Check for Shaft Play:
The technician checks all shafts for any play or wobble. If there’s any movement, it could indicate a more significant problem that needs attention before it worsens. - Inspect the Bearings:
Each bearing is checked for signs of wear. Worn bearings can lead to grinding, noise, and eventually breakdown, so they must be addressed promptly. - Assess the Feed Dog Mechanism:
The technician inspects the mechanism that drives the feed dogs for any play. The feed dogs need to be tight and functioning smoothly to ensure consistent fabric feeding. - Check Feed Dog Height and Alignment:
The technician checks the feed dog height. Even the smallest misalignment can affect how the fabric is pulled through the machine, leading to inconsistent stitching. - Check Feed Dog Alignment with stitch plate:
The feed dogs are checked for alignment with the stitch plate to ensure they’re straight and not rubbing. Any rubbing can cause uneven feed and poor stitching results. - Examine the Gears:
All gears driving the machine are checked for wear. Worn or loose gears can cause significant issues, and any necessary adjustments are made to keep everything running properly. - Remove and Inspect the Hook Driver:
The hook in the bobbin case area is checked for proper movement. Excess play between the hook, hook driver, and clutch carrier can cause skipped stitches or inconsistent thread tension. - Center the Needle:
The technician checks that the needle is centered correctly in the needle plate—both side-to-side and front-to-back. A slight misalignment can lead to needle breakage, especially when sewing heavy fabrics or wide stitches. - Check Needle and Hook Timing:
The timing between the needle and hook is checked to ensure smooth operation. Incorrect timing can result in skipped stitches and other frustrating issues. - Adjust the Presser Foot:
The presser foot is checked to ensure it sits correctly on the feed dogs and is at the proper height and operating at the correct downward pressure. If it’s too high or too low, it will negatively impact fabric feeding and stitch quality. - Sync the Feed Dogs to the Needle:
The feed dog movement is timed to the needle to ensure they work together seamlessly. This synchronization is essential for consistent, perfect stitching. - Calibrate the Bobbin Case Tension:
The technician calibrates the bobbin case tension with factory weights for optimal performance. Too tight or too loose, and the stitching will be affected—this step ensures it’s just right. - Clean the Bobbin Case:
The bobbin case is thoroughly cleaned of any excess lint or debris. A clean bobbin case means smoother operation and fewer problems with thread tension. - Thread Cutter
Remove, inspect, clean, adjust, and set timing of thread cutter. Replace blade and/or assembly if damaged. - Set/Reset tension
adjust or reset top tension using factory procedures or weights if applicable. - Stepper motors
Check proper operation of all step motors (up to 9) - Knobs
check all knobs and controls for proper operation and correct as necessary. - Screen
Calibrate the screen - Inspect the Foot Control:
The technician checks the foot control for any damage or wear. They inspect the cord, cord end, and electronic contacts for any issues, ensuring the foot control is functioning smoothly. - Tighten Loose Gears:
Any loose or wobbly gears are tightened to prevent further damage. Tight gears are essential for maintaining a smooth, efficient operation. - Test the Bobbin Winder:
The technician checks the bobbin winder for symmetry and adjusts as necessary. A malfunctioning winder might seem minor, but it can create a huge headache later on, so it gets a thorough inspection. - Identify and correct any other issues discovered.
- Lubricate all moving parts. Bernina has 9 different lubricating oils depending on the machine and parts being serviced. Lack of yearly maintenance or failure to use the correct lubricant will reduce machine life and may even interfere with proper operation.
- Return to Factory Specs:
Use factory jig tools to adjust machine to factory specifications. - Test:
Sew out and fine tune for mechanical balance and optimal stitch quality.
By following this meticulous process, our technicians ensure that every component of the machine is in top working order. The result? A sewing machine that runs as well as possible, stays reliable, and avoids costly repairs down the road. Regular service is a smart way to protect your investment and ensure a long-lasting, precision machine.