The Lincoln Electric Magnum SG Spool Gun Air-Cooled 25 ft (K487-25) is Lincoln’s classic air-cooled spool gun for aluminum wire welding, featuring a 25 ft cable that connects directly to compatible Lincoln wire feeders and MIG welders. The K487-25 has been a trusted platform for aluminum MIG welding in fabrication shops, shipyards, and field service applications for decades.
| Model | Magnum SG Spool Gun, Air-Cooled |
|---|---|
| Part Number | K487-25 |
| Cable Length | 25 ft (7.6 m) |
| Cooling | Air-cooled |
| Wire Diameter Range | 0.030 in – 3/64 in (0.8 – 1.2 mm) |
| Wire Capacity | 1 lb (4 in) small spools |
| Compatibility | Lincoln Electric wire feeders and MIG welders with Magnum SG gun receptacle |
| Connector Type | Lincoln Magnum SG connector (adapter may be required for some machines — see Compatibility) |
| Vendor | Lincoln Electric |
- Aluminum wire MIG welding: The K487-25 is purpose-built for 4000- and 5000-series aluminum wire. Wire feeds pull-style from a 1 lb spool at the gun, bypassing the long push liner entirely and delivering smooth, consistent arc performance on aluminum.
- Soft-alloy materials: Silicon-bronze, soft stainless, and other deformable wire alloys benefit from the same short-feed-path design, reducing the frustrating stop-and-trim cycles of conventional MIG gun setups.
- Marine, automotive, and HVAC fabrication: At 25 ft of cable length, the K487-25 gives fabricators working on large aluminum assemblies the room to move around the workpiece without repositioning the power source.
- Shops upgrading from standard MIG to aluminum capability: The K487-25 is often the first spool gun welders add to an existing Lincoln setup — it requires no new welder, only a compatible machine and the gun itself.
The K487-25 Magnum SG is designed for Lincoln Electric wire feeders and MIG welders equipped with the Magnum SG gun port. Common compatible platforms include the Lincoln LN-25 series wire feeders and select Power MIG models. An adapter cable (such as the one included in the K1809-1 kit) may be required for machines that do not have a native Magnum SG port.
If you are adding a spool gun to a Lincoln welder that currently runs a standard Magnum gun, confirm that your machine’s control board supports spool gun operation — some older models require a firmware update or adapter. WeldingMart’s team can help you verify this before purchase.
See all Lincoln and brand-compatible spool guns in our Spool Guns collection.
WeldingMart is an authorized Lincoln Electric distributor. The K487-25 you order from us is a genuine Lincoln Electric product backed by the full manufacturer warranty — not a gray-market import or unauthorized copy. We have stocked the Magnum SG line for years and our team can answer compatibility questions for your specific machine. US shipping, expert support, and genuine Lincoln product — that is the WeldingMart difference.