5 Tool Holders Tool holders such as the ISO 30 have additional matching and

5 tool holders tool holders such as the iso 30 have

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to examine the clamping nut threads on a regular basis. 5. Tool Holders Tool holders such as the ISO 30 have additional matching and mating tolerances beyond those of the older tapers. Because of their unique design, these tool-holding systems can be more prone to runout caused by resin buildup. “Fretting” or “Bronzing” will cause inconsistent gripping in the taper and / or the flat mating surface and reduce consistency of tool life. If ignored, these conditions can eventually produce premature spindle failure. The mating surfaces should be cleaned regularly. All of these components are critical and should be regularly maintained. One more item not to be overlooked is that collets should be replaced on a regular basis, approximately every 400 to 600 run time hours. This means inspection for metallic damage such as bell mouthing or burrs with every tool change. If damage is visible, the collet should be discarded and replaced. Also consider that even if there is no damage present the collet can be worn out through metal fatigue. Heat is directly transferred from the tool to the collet. These heating / cooling cycles remove the original tempering of the steel. Collets are made from spring steel allowing them to have a certain amount of elasticity to grip the tool. As the heat cycle is repeated this elasticity diminishes. Over time, a collet requires increased tightening to maintain the tool in proper position. As over tightening increases, the collet is distorted, creating eccentricities in the tool holder. Therefore, instead of over tightening older collets and creating a number of other problems, the collet should be replaced. Often the cost of a new collet can be offset by the cost of needlessly broken tools in one shift alone.
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32 Troubleshooting Cutting Problems For every problem there is a possible cause and a solution. Here are some typical problems that you may encounter and possible solution for each problem. Problem Cause Solution Tool Breakage Heat buildup due to incorrect tool selection Use correct tool for material being cut Heat due to inadequate chip removal Use up spiral tool to help in chip removal Too high a plunge rate Reduce plunge rate Blunt tool Replace tool Tool runout Tighten tool in collet or if necessary change collet Worn collet Replace collet Too high a feed rate Reduce feed rate Too high a chip load Reduce feed rate or increase RPM or change tool to one with more flutes Vibration Improve workpiece hold down to machine bed Tool not fitted correctly in Re-fit tool in collet ensuring at least 80% collet of collet length is used Tool deflection Reduce feed rate but if possible use larger diameter tool Poor cut finish due to No coolant Use mist coolant or cold air gun chip rewelding to cut edge Blunt tool Replace tool Too slow a feed rate Increase feed rate Incorrect tool selection Choose correct tool for material being for material machined Heat due to inadequate chip removal Use up spiral tool
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33 The AXYZ Series CNC routers are the cornerstone of the entire AXYZ International product line. The
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  • Fall '19
  • Tools
  • Día, Orders of magnitude, Flute, Tungsten carbide, Collet

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