This is a long multi-station integrated manifold block, which can also act as a mounting beam, machined from long aluminum bar stock. Several groups of counterbores, locating holes, and mounting holes are evenly spaced along its length, and the body has a stepped, sectioned profile. The surface is finish machined.

Flatness over the full length, hole-to-hole spacing between groups, and squareness of the holes to the datum face are all tightly controlled. It is typically used for integrated pneumatic circuits across multiple stations, or as the main mounting beam for a module.

Machining Challenges

• The part is long and slender with low rigidity. It bends and chatters easily during machining, and holding full-length flatness is difficult.
• Several hole groups are spread along the length. The risk of cumulative hole spacing error is high, so positioning accuracy matters.
• The steps are staggered, with holes on both the front and back faces. Flipping the part repeatedly can shift the datum.
• A long part releases stress after roughing. Side bow can appear and is hard to correct during finishing.
• Counterbore depth must be consistent. Step marks can show up on the counterbore floors.

How It’s Managed

Issue	Approach
Clamping distortion	Vacuum holding combined with side clamps to reduce clamping distortion
Stress release and side bow	Stock left on after roughing, then the part is left to rest for stress relief before finishing
Cumulative hole spacing error	Datum indicated in once, with a common coordinate system across the program to control accumulated spacing error
Counterbore quality	Counterbores finish milled, with feed and speed tuned to remove step marks
Inspection	Full-length flatness, hole spacing, and counterbore depth spot-checked on a CMM