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Southland CNC of Cornelia, Georgia is a Tier Two supplier to the automotive industry, providing machined aluminum sand-cast components to all three American and the six largest foreign auto manufacturers. The company, which was started 19 years ago in President/Owner Keith Armour’s garage on a single machine, has now grown to 30 employees using 21 high-capacity machining centers.

Southland machines a variety of parts that includes production runs of very high volumes and other production runs of relatively low volume. Southland uses dedicated hydraulic clamping fixtures on Okuma Howa vertical machining centers for its high volume production runs, because these fixtures greatly decrease production time, which makes the fixturing highly cost-effective. The dedicated hydraulic fixtures also provide clamping pressure that is consistent and repeatable, which improves machining accuracy. According to Keith Armour, the typical tolerances are held to 20 microns true position, with critical dimensions to +/- 6 microns, which he credits largely to the hydraulic fixturing supplied by Southland’s longtime supplier, Advanced Machine & Engineering (AME) of Rockford, Illinois. Because low volume production runs do not justify dedicated fixturing, Southland uses manual fixturing for its adaptability and lower cost of acquisition, when appropriate.

Southland currently has four horizontal machining centers that use hydraulic tombstone fixturing, and three vertical machining centers that use hydraulic tombstone fixturing, all designed and built by AME. These fixtures are dedicated to high volume production of single parts or single families of parts.

Southland chose AME to provide its first tombstone hydraulic fixture because the fixturing solution was competitively priced and specifically designed by AME engineering to fit Southland’s production needs. Delivery, which was very important to Southland’s production scheduling, was significantly better than any other designer/supplier, according to Armour. The first AME fixture specifically replaced the customer-supplied fixturing Southland had been using, which Southland determined was not providing the efficiency needed to meet cost and schedule goals for the high volume production run.

The advantages provided by the AME-designed fixture included reduced load/unload time, reduced cycle time, reduced scrap rates, and error-free loading. The initial application of the fixture reduced Southland’s cycle time by over 50 percent, which allowed Southland to meet the high production volume without additional machines. On one bearing plate for a supercharger assembly, according to Keith Armour, production has gone from 50 units to 110 units per day with the same superior tolerances and a 1.67 Cpk, critical to the Six Sigma conformity for its major automotive customers.