Quick answer: The Model F portable bag closer is a 12 lb handheld bag sewer that sews a single-thread stitch at 38 feet per minute (3.75 stitches per inch). It closes plastic, woven polypropylene, multi-wall paper, composite and jute bags and runs on 115V or 230V. Options include a 2" crepe tape attachment for a neater, more leak-resistant top and a spring suspension unit that holds the machine above the work area between bags.
The Model F handles a wide mix of bag types, including plastic and composite bags. Below are its specs, how to set it up, how to keep it running, and fixes for the most common problems, based on the Model F product page and operating manual.
Model F specifications
| Type | Handheld portable bag closer, single-thread |
| Sewing speed | 38 ft/min (11.6 m/min); 1,830 RPM max at full load |
| Stitch length | Average 3.75 stitches per inch (6.8 mm per stitch) |
| Weight | 12 lb (5.4 kg) |
| Dimensions | 12 x 13 x 10 in (305 x 330 x 254 mm) |
| Power | 115V or 230V |
| Lubrication | Manual oiling system (oil pump) |
| Bag materials | Plastic, woven polypropylene, multi-wall paper, composite, jute |
| Options | 2" crepe tape attachment; suspension unit |
Who the Model F is for
- Operations closing a mix of bag types, including plastic and composite bags
- Filling stations where one operator closes bags by hand at lower volumes
- Anyone who wants a crepe tape closure without buying a pedestal tape sewing head
- Workstations where a suspension unit keeps the closer off the floor and within reach
How to sew a bag with the Model F
- Fill and stand the bag. Leave room at the top. The manual says to sew 4 to 6 inches (102 to 152 mm) above the product, and not farther than four inches down from the top.
- Start the machine at the edge of the bag top and let it feed itself across.
- Don't pull or hold back. The manual is clear: let the machine do the work. Pulling the bag through, holding back the bag or machine, or pulling up on the machine gives poor stitch quality.
- Run off the end so the thread chain forms and is cut.
Daily startup checklist (from the manual)
- Check for loose fasteners
- Make sure the oil reservoir is full
- Push the oil pump four times to lubricate the moving parts
- Check the electrical connection
- Make sure the thread is properly threaded and chained off
- Remove dirt and debris
- Run a couple of test bags
Maintenance schedule
- Every four hours of operation: apply oil from the pump.
- Daily: keep the machine free of dust and dirt, and wipe excess oil from parts.
- Weekly: clean the machine in cleaning solution as described in the manual.
- Every 100 hours: check the motor brushes. Replace them if they're shorter than ¼ inch (6 mm).
- Parts: the manual calls for genuine Fischbein needles, oil and spare parts. Using other parts can void the warranty.
Troubleshooting common Model F problems
| Problem | What to check |
|---|---|
| Skipped stitches or poor stitch quality | Stop pulling or holding the bag; confirm the needle passes through the middle of the needle guard; replace dull feed dog teeth |
| Thread breaking | Thread tension; bent or dull needle; threading path |
| Chain won't start; needle breaks after threading | After threading, turn the pulley by hand clockwise through at least three complete cycles to start the chain |
| Thread fibers look torn instead of cut | Thread knife blades may be dull; replace them |
| Motor issues | Check brushes every 100 hours; replace below ¼" (6 mm) |
Safety
- Wear proper eye, hand and foot protection, and tie back long hair.
- Turn off power before maintenance.
- Clean frequently to prevent dust buildup.
- Model F machines are not suitable for areas where explosive materials are present.
When to choose a different closer
If you need DC power, the NP-7A comes in 12V and 24V DC versions. If you're closing bags on a conveyor all day, a pedestal head like the Model 100 or Empress Model 101 is the next step.
Frequently asked questions
What is the Model F portable bag closer?
The Model F is a 12 lb handheld bag closer that sews a single-thread stitch at 38 feet per minute, averaging 3.75 stitches per inch. It closes plastic, woven polypropylene, multi-wall paper, composite and jute bags and runs on 115V or 230V.
How fast does the Model F sew?
The Model F sews at 38 feet per minute (11.6 meters per minute), with a maximum speed of 1,830 RPM at full load.
How often do I oil a Model F bag closer?
According to the Model F manual, press the oil pump button four times before operation to lubricate the moving parts, then apply oil from the pump every four hours of operation. Keep the oil reservoir full and use the lubricating oil the manual specifies.
How far down from the top should I sew a bag with the Model F?
The Model F manual says to sew 4 to 6 inches (102 to 152 mm) above the product in the bag, and not to sew farther than four inches down from the top of the bag.
Why is my Model F skipping stitches?
The most common cause is interfering with the feed. The manual warns that pulling the bag through, holding back the bag or machine, or pulling up on the machine gives poor stitch quality. Let the machine feed itself. Also check that the needle passes through the middle of the needle guard and that the feed dog teeth aren't dull.
Why does the thread keep breaking on my Model F?
Check the thread tension first, because improper tension will cause the thread to tear. Then check that the needle isn't bent or dull, and that the thread is properly threaded through the machine.
What is the Model F suspension unit?
The optional suspension unit holds the Model F up until the operator is ready to use it. The operator pulls the machine down to bag-top level to sew, and when released, the spring-loaded unit retracts the machine back to its home position.
Can the Model F apply crepe tape?
Yes. An optional 2-inch crepe tape attachment applies tape over the bag top as the Model F sews.
Can the Model F be used around explosive materials?
No. The Model F manual states that Model F machines are not suitable to operate in an area where explosive materials are present.
Questions about the Model F?
Tell us your bag material, product and how many bags you close a day, and we'll recommend the right closer. Call 866-888-6327 (Mon–Fri, 8am–5pm CST), email sales@clevelandequipment.com, or browse all bag sewers.