51700M - Sewing machine Union Special - Free user manual and instructions
Find the device manual for free 51700M Union Special in PDF.
Pick your language and provide your email: we'll send you a specifically translated version.
| Product Type | Industrial Overlock Sewing Machine |
| Model | 51700M |
| Brand | Union Special |
| Dimensions (L x W x H) | Approx. 500 x 400 x 400 mm (19.7 x 15.7 x 15.7 in) |
| Weight | Approx. 25 kg (55 lbs) |
| Power Supply | 220-240 V, 50/60 Hz, 1-phase or 3-phase depending on configuration |
| Motor Power | 550 W clutch motor (standard) |
| Maximum Sewing Speed | 6000 stitches per minute |
| Number of Threads | 3 or 4 (convertible) |
| Stitch Type | Overlock, safety stitch, chain stitch |
| Needle System | DC X 27 or similar industrial needles |
| Lubrication | Automatic oiling system with oil reservoir |
| Maintenance | Regular cleaning of lint; oil level check; needle replacement |
| Safety Features | Safety switch on presser foot; hand wheel lock; needle guard |
| Spare Parts Availability | Widely available through industrial sewing machine dealers |
| Reparability | Modular design; many parts user-replaceable with standard tools |
| Included Accessories | Knee lifter, spare needles, oil bottle, screwdrivers |
| General Information | Heavy-duty machine for denim, canvas, and other thick fabrics; used in garment manufacturing |
Frequently Asked Questions - 51700M Union Special
What type of thread should I use with this machine?
For industrial overlock machines, use thread cones with a tex rating of 40-60. Avoid home sewing spools as they may cause tension issues.
How do I adjust the stitch length?
Locate the stitch length adjustment knob on the left side of the machine. Turn it to increase or decrease the stitch length. Typical range is 1-5 mm.
My machine is skipping stitches. What should I check?
First, check the needle for damage or dullness. Replace if necessary. Then ensure the threading is correct and the tension settings are appropriate. Also verify the looper timing.
How often should I oil the machine?
The machine has an automatic oiling system, but you should check the oil level daily. Refill the reservoir with industrial sewing machine oil to the indicated line.
Can I sew through very thick fabrics like denim or leather?
Yes, the 51700M is designed for heavy-duty materials. Use a heavy-duty needle (size 18-21) and reduce the sewing speed for better control.
What is the difference between 3-thread and 4-throat overlock?
A 3-thread overlock uses three cones to form a narrow seam, while a 4-thread adds a chain stitch for extra strength. This machine is convertible between both modes.
How do I change the needle?
Turn off the machine. Loosen the needle clamp screw with a screwdriver. Remove the old needle and insert a new one with the flat side facing away from you. Tighten the screw securely.
Why is the fabric not feeding evenly?
Check the presser foot pressure adjustment. Ensure the feed dogs are not worn. Clean any lint from the feed dog area. Also verify that the differential feed ratio is set correctly.
Where can I find replacement parts?
Authorized Union Special dealers carry genuine parts. Many generic parts also fit. Check online industrial sewing machine suppliers or contact your local dealer.
What safety precautions should I take?
Always disconnect power before threading or cleaning. Keep hands away from the needle area. Use the safety guard provided. Do not wear loose clothing that could get caught.
User questions about 51700M Union Special
0 question about this device. Answer the ones you know or ask your own.
Ask a new question about this device
No questions yet. Be the first to ask one.
Download the instructions for your Sewing machine in PDF format for free! Find your manual 51700M - Union Special and take your electronic device back in hand. On this page are published all the documents necessary for the use of your device. 51700M by Union Special.
USER MANUAL 51700M Union Special
Manual assistant
Powered by Anthropic
Waiting for your message
Product information
Brand : Union Special
Model : 51700M
Category : Sewing machine