Definition of 4th Axis CNC Machining Capability
The reason this matters to a buyer is setups. Every time a part is unclamped and reclamped, a small positional error is introduced between the features cut before and after. Cutting in one setup removes that error, which is how tight position and concentricity callouts between faces are met. It also removes labor, since one operator load covers what would otherwise be two or three.
Parts that benefit include valve bodies, pneumatic tool housings, manifold blocks and any casting with holes or faces on more than one plane. JoinCast runs 4th axis work alongside standard 3 axis milling and lathe turning at its Taichung plant, so parts are routed to the machine the geometry actually needs.
Why This Matters for Your Business
For a procurement manager this shows up as a quotation that looks expensive per machine hour but cheaper per finished part, and as a lower first article rejection rate on position callouts. Asking a supplier how many setups your part will take is often more informative than asking what machines it owns.
It also bears on lead time. Fewer setups mean less fixture design before production starts, which matters when you are working to a fixed launch date.
FAQ
When does an aluminum die cast part actually require 4th axis CNC machining capability?
4th axis CNC machining capability becomes necessary when a part carries machined features on more than one plane and those features have to be positioned accurately relative to each other. A housing with a bore on the front face and cross-drilled ports on the side is the standard case.If every machined feature sits on one plane, a 3 axis center will do the work at a lower rate. Send your drawing and ask which operations the supplier plans and how many setups each one requires. Our CNC automation systems at JoinCast describe how we route parts between machine types and where the rotary work sits.
How does 4th axis CNC machining capability affect unit cost and lead time?
4th axis CNC machining capability usually raises the machine rate and lowers the total cost per finished part, because one setup replaces two or three. The saving grows with volume, since fixture and programming time is spread across more pieces.On a short run of a few hundred parts, the setup saving may not cover the fixture cost, and a 3 axis route can be cheaper. Lead time tends to improve for the same reason: fewer fixtures to design and prove out before production. Ask the supplier to quote both routes if your volume sits near the crossover. Our CNC machining capabilities at JoinCast list the machine types available for each route.
What fixturing is required for 4th axis CNC machining capability on a die casting?
4th axis CNC machining capability depends on a fixture that holds the casting square to the rotary axis and repeats that position part after part. On an aluminum die casting the fixture usually clamps on as-cast datum pads or on a face machined in the first operation, since general as-cast surfaces carry draft and vary within the casting tolerance.A supplier should tell you which surfaces it intends to use as datums before it builds the fixture, because that choice decides where your tolerances accumulate. Our mold engineering capabilities at JoinCast cover how datum pads are designed into the tool at the outset.
