Interlock machine is a stretch stich sewing machine generally used in garments factory. We need to adjust different variable of a stretch stitch sewing machine like adjusting tension, adjusting needle and thread, adjusting spreader thread, adjusting stitch length, adjusting differential feed ratio, adjusting presser foot, adjusting presser foot pressure etc. We need to manage light near the sewing machine. Cleaning the sewing machine and oiling the sewing machine is very necessary.
How to Adjust Tension on Sewing Machine:
The tension of the thread should be adjusted according to:
- The material type
- The thickness of the fabric sewed,
- The thread,
- The stitch length,
If you turn the thread tension knob clockwise, thread will be tighter. If you turn it counter –clockwise, will be looser.
Adjusting Needle and Thread of Interlock Machine:
When turning the pulley and make the needle bar in the lowest position, the top edge of the needle and thread take-up (1) should remain horizontal. To adjust the position of take up if necessary, loosen the screw (4). Loosen screw (2) to adjust the length between point A and B to be about 81.5mm, then fasten it tightly. To loosen the needle and thread turns the needle and thread take up (3) toward the left. To tighten the needle take up (3) toward the right. Do not move the spreader thread take up (5)
Adjusting Spreader Thread Take Up:
When the spreader thread take up (1) is adjusted to the top, the small hole A to the other spreader thread take up (2) must be at the same level with the long grove of the spreader thread take up (1). For necessary adjustment loosen screw (3) and (4) first, move the spreader take up (2) up and down, and then fasten the screws again.
How to Adjust Stitch Length:
Stitch length can be adjusted variably in range from 1.6mm-4.2mm or 6-16 stitch per inch. Keep pressing the push button A with the left hand, then turn the hand –wheel with the right hand until you feel the push button lick in.
Keep turning the hand –wheel for a inquired stitch length. Turn the pulley and align the inquired the button. Rotate the hand-wheel clockwise to increase the stich length and counter clockwise to decrease.
Adjusting the stitch length will change the differential feed ratio, therefore after adjusting the stitch length, please adjust the differential feed ratio.
Adjusting Differential Feed Ratio:
The differential feed ratio of this machine is adjustable from 1:0.5 to 1:1.3. To adjust the ratio loosen the nut (2), move the indicator (1) up or down. To stretch the cloth moves the indicator (1) upward. To gather the cloth moves the indicator (1) downward.
Do not adjust screws freely (3)(4) to prevent the feed teeth colliding with the needle plate when the stitch length is the longest and the differential ratio is the biggest. If it is necessary to adjust, please shorten the stitch length.
Adjusting Presser Foot:
Loosen screw (1) and adjust presser foot (2) left and right to a proper position to let the needle may get into the center of presser foots eyelet.
How to Adjust Presser Foot Pressure:
If the fabric is fed smoothly and has perfect sewing the pressure foot could be adjusted to be lightened.Loosen the unit A and turn the screw B clockwise to increase the pressure turn it counterclockwise to decrease the pressure
Lightening of the Operation Environment:
Provide a warning that an industrial sewing unit or sewing system must always be unplugged form the local lightening of the sewing area before relamping, the marking of maximum rated input of a lamp shall be easily discernible while the lamp I being replaced.
Clean Sewing Machine:
- Raise the pressure foot.
- Remove the two screws (1) and then remove the needle plate (2)
- Use a soft brush to clean dust and lints on the feed dog teeth (3)
- Install the needle plate (2) after doing the above cleaning.
- Tilt back the machine head.
- Periodical Maintenance Items to Clean Sewing Machine
Lubrication of Sewing Machine by Sewing Machine Oil:
Please use a Mobil #10 or sewing machine oil or its equivalent lubricant. The sewing machine oil has been drained from the machine before delivery. Therefore before using the new machine remove the oil until the oil level is between the high /low indicate lines of oil level gauge.
Before sure to check the sewing machine oil level every day and refill l the sewing machine oil if oil level is lower than the lower indicate line of sewing machine oil level gauge. When the machine starts functioning check the lubrication system to see if it is well functioned before operating the machine.
Standard Opereating Procedure of Sewing Needle:
To make sure that all metal equipment such as needles, hand sewing needles, kimball guns, scissors, snips, pins, etc. is held under control during the manufacturing processes and that all products manufactured for Auto do not contain any hazardous metal materials that could harm the customers.This procedure is applicable to all our ready-to-wear suppliers.
- Suppliers: The suppliers are bound to comply with all the conditions stated in this memorandum and take necessary precautions in the light of warnings provided.
- Auto Auditors: Auto auditors will pay random visits to the suppliers to make sure that the suppliers comply with all the conditions stated in this procedure.
- The equipment that has been given to the operators by the Department Supervisors should be attached to work benches to stop accidental loss.
- The supervisors must check equipment periodically and withdraw any equipment found not fit for purpose.
- Only the supervisors or nominated personnel can issue replacement needles, or equipment. Spare needles, kimball guns, scissors are not allowed at the work station.
- The supervisors should keep the metal equipment in secured and locked cabinets. The cabinets are always locked and keys are kept only by the supervisors or a nominated employee.
- Mechanics/operators should pay extra attention to ensure that tools or instruments do not get lost in garments.
- Staples must not be used in any operation or in the sewing room.
- Pins must not be used in the packaging of any product.
- Razors must not be used as cutters. If cutting of this type is needed, a modeling knife/scalpel with a secure blade must be used.
- Scissors and clippers should be tied to the workplace to prevent potential loss within a product. If it is not possible to tie them, then they should be logged in/out at the beginning/end of each shift.
- Personal items such as keys, hairgrips, jewellery, etc. cannot be placed on/near machines or/and tables.
- If a product is found to be contaminated with metal fragments and the metal cannot be found after thorough inspection, then the product must be placed in a sealed locked container labeled Contaminated Stock by the Department Supervisors, and recorded in the Metal Detected Stock Sheet.
Applıcatıon Of The Broken Needle Polıcy:
- All needles must be accounted for in all operations of the manufacturing process. This is ensured with the implementation of the Needle Change Report.
- Whenever a needle break occurs, every effort must be made to recover all of the broken pieces before the manufacturing starts again and the products move onto the next process. Needle parts need to be checked against a profile or new complete needle to ensure that all parts are found.
- If a needle breaks during a manufacturing process, machine operator should stop working and inform the Department Supervisor. The incident should be recorded with all relevant information on the Broken Needle Report and all parts of the broken needle should be collected immediately and affixed on the report with a large, transparent adhesive tape.
- If all parts of a broken needle are not found, then the products on which the operator is working, and any others in close proximity to the machine and workspace must be checked. If all parts are still not found, all products must be removed and packed into a polybag and passed through the metal detector in order to isolate any products containing metal fragments. These products must be thoroughly examined in a quarantined area until the missing needle parts are found. This must be recorded in the Metal Detected Stock Sheet. If, for any reason, all parts of the needle cannot be found, the products need to be put into a sealed locked container labeled Contaminated Stock and must be recorded in the Metal Detected Stock Sheet accordingly.
- New needle can only be attached to the machine when the broken needle is found and accounted for. Then the machine operator can continue working.
- Broken Needle Reports must be kept for a minimum of three years, and there after disposed off in sealed containers. Auto Auditors will check these reports randomly.