High Volume Automotive Powertrain:18mm four-flute endmill. Customer ran production for 1 year with chatter. Feed rates slowed down to improve surface finish, but sound levels in area were of concern (this was the loudest process over 95 dBA). Stability Diagram made and new 4 flute tool recommended at new RPM. Sound level reduced to near ambient (83 dBA). Surface finish improved, tool cost decreased, and productivity increased after feed rate was doubled (thanks to a stable RPM). Listen to the sound files:
Before, 4 flute Carbide, 7953rpm, 1000 mm/min, 3mm Ae, 35mm Ap
Optimized, 4 flute Carbide, 6200rpm, 2000 mm/min, 3mm Ae, 35mm Ap
Small Machine Shop Aluminum Mounting Component: Chatter on entry level CNC with 10:1 Length/Diameter 0.25” two-flute endmill. Customer tested 6 types of tools and holders to improve process, with minimal success. In 1 hour of analysis and test cuts, D3V recommended new RPM, DOC, and Feed combination using the Chatter Frequency Data in Harmonizer®. Using existing tool the customer reprocessed using new parameters that reduced cycle time by 1.8 minutes and eliminated finish pass due to improved surface finish. D3V solution cost $1000 and half a day onsite, and saved company $6600/year (300 parts/month * .0305 hr/part savings* $60/hr) Case Study Small Shop
High Tech Aerospace Development Project for Titanium: Random chatter with multiple endmills on high end HSK 100 horizontal CNC during deep low-radial immersion finish endmilling using less than 10% of spindle power. Customer spent 3 months tested numerous tool and toolholder designs and large DOE with different cutting parameters. D3V analyzed chatter from 3 different tools and located a machine design stiffness issue. Machine builder used information to redesign the machine. D3V solution cost $5,000 and 2 days onsite, and customer improved process 300% over original parameters with no random chatter.
High Production Automotive Steel Tubing: Random tool breakage and poor tool life for a 10 mm endmill (20 minutes, 20 parts, $200/tool) cost $10/part. Customer worked for 15 months with machine tool integrator and 4 tooling companies to improve tool cost. Numerous tool tests and addition clamping was added to machine with minimal success. D3V analyzed the tool and part structures and determined the tool/holder/spindle was the weak structure and recommended new RPM and Feed based on the Stability Diagram, and to use a standard endmill. D3V solution cost $8,000 and 3 days onsite, and customer cost reduced to $0.81/part (80 parts, $65/tool). Customer saved $9.19/minute or approximate $250,000/year.
Case Study showing Max RPM not always most productive
Case Study Small Prototype Shop using classic techniques in 6061