1. Introduction
The SENTRO 40-Needle Knitting Machine is designed to simplify the knitting process, allowing users to create a variety of knitted items efficiently. This manual provides comprehensive instructions for setup, operation, and maintenance to ensure optimal performance and longevity of your machine. It is suitable for both beginners and experienced knitters looking to expedite their projects.

Figure 1: SENTRO 40-Needle Knitting Machine and included accessories.
2. Product Overview
2.1 Included Components
- SENTRO 40-Needle Knitting Machine
- Crochet Hook
- Needles
- Screwdriver
- Yarn (starter quantity)
2.2 Key Features
- 40 Needles: Allows for efficient creation of various knitted items.
- Double Mode: Supports both 'T' (Tube/Circular) and 'P' (Panel/Flat) knitting modes.
- Row Counter: Integrated counter to track the number of rows knitted.
- Tension Adjuster: A lever to control yarn tension for consistent stitches.
- Hand-Crank Operation: Manual operation for ease of use without power.

Figure 2: The knitting machine ready for use with yarn.
3. Setup
- Place the knitting machine on a stable, flat surface. Ensure the suction cups (if present) are securely attached to prevent movement during operation.
- Identify the 'T' (Tube/Circular) and 'P' (Panel/Flat) mode switch. Select the desired knitting mode by sliding the switch.
- Locate the tension lever. This component helps regulate the yarn's tightness as it feeds into the machine.
4. Operating Instructions
4.1 Casting On (Starting a Project)
- Ensure the mode switch is set to 'T' (Tube) for circular projects or 'P' (Panel) for flat projects.
- Hold the yarn tail and thread it through the white yarn guide.
- Starting from the first white needle (or a designated starting needle), wrap the yarn around the needles in an alternating pattern: one needle in front, the next behind, and so on. Continue this for one full rotation.
- Once the first rotation is complete, feed the yarn through the tension lever, selecting the appropriate tension setting (loose, medium, or tight).
- Begin turning the hand crank slowly and steadily. The machine will start forming stitches.
4.2 Knitting Modes

Figure 3: Mode switch for 'P' (Flat) and 'T' (Tube) knitting.
- 'T' (Tube/Circular) Mode: For seamless, tubular items like hats, scarves, or socks. The machine will knit continuously in a circle.
- 'P' (Panel/Flat) Mode: For flat pieces like blankets or panels for garments. The machine will knit back and forth, reversing direction at the end of each row.
4.3 Tension Adjustment
The tension lever allows you to control the tightness of your stitches. Experiment with different settings (loose, medium, tight) to achieve the desired fabric density for your project. For an extra tight tension, you can thread your yarn through 2 or 3 spaces on the tension lever.

Figure 4: The tension lever with various settings.
4.4 Changing Colors
To change yarn colors, simply cut the current yarn, leaving a tail. Tie the new yarn color to the tail of the old yarn with a secure knot. Continue knitting, ensuring the knot passes smoothly through the needles. Trim any excess yarn tails after a few rows.
4.5 Casting Off (Finishing a Project)
Once your project has reached the desired length, cut the yarn, leaving a long tail (approximately 3-4 times the circumference of your project). Thread this tail onto the included needle. Slowly turn the crank, using the needle to pick up each loop from the machine's needles as they become accessible. Continue until all loops are off the machine. Pull the yarn tail to gather and secure the stitches.
4.6 Instructional Videos
Video 1: Demonstration of the SENTRO Knitting Machine in operation, showcasing its use for various projects.
Video 2: Step-by-step guide on how to start knitting a beanie using the machine.
5. Maintenance
- Regularly clean the machine to prevent lint and yarn fibers from accumulating in the needles and gears. Use a soft brush or cloth.
- Store the machine in a dry, dust-free environment when not in use.
- Avoid forcing the crank if it jams. Investigate the cause (e.g., tangled yarn, dropped stitch) before resuming operation.
6. Troubleshooting
- Dropped Stitches: This can occur if the yarn tension is too loose, the crank is turned too quickly, or the yarn is not properly fed. Ensure consistent tension and a steady cranking speed. Re-hook any dropped stitches using the crochet hook.
- Yarn Jams: Often caused by incorrect yarn threading, overly thick yarn, or uneven tension. Check that the yarn is correctly seated in the tension guide and not tangled.
- Uneven Fabric: Adjust the tension lever to achieve a more consistent stitch size. Ensure the yarn is feeding smoothly without snags.
7. Specifications
- Brand: SENTRO
- Model Name: SENTRO knitting machine 840A
- Item Model Number: 840A
- Number of Needles: 40
- Material: Plastic
- Product Dimensions (L x W x H): 13.78 x 13.78 x 9.06 inches
- Item Weight: 3.09 pounds (1400 Grams)
- UPC: 780262758368

Figure 5: Product dimensions of the knitting machine.
8. Warranty and Support
For specific warranty information regarding your SENTRO 40-Needle Knitting Machine, please refer to the documentation included with your purchase. For further technical assistance, troubleshooting, or inquiries about replacement parts, please contact SENTRO customer support through the retailer where the product was purchased.



