This allows harder materials to be handled Upcut spirals are the most popular

This allows harder materials to be handled upcut

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This allows harder materials to be handled. Upcut spirals are the most popular type of spiral fluted tool. Use these for grooving or slotting, for upward chip evacuation and best finish on the bottom side of the part. These bits allow for rapid cuts since the tool clears the chips away from the material. This type of tool is not recommended for softer materials because of the ragged finish that can result on the top surface. This type of geometry is used whenever the best finish is needed on the bottom side of a part. Downcut spiral tools are best used for thinner materials which will be pushed down into the machine bed rather than being lifted with an upcut spiral. They are also best for leaving a good cut finish on the top surface of cut parts. Note that the cutting speeds usually have to be reduced because the chips are pushed back into the material. Chip extraction is generally less effective with this type of tool than it is with upcut spiral tools. Chipbreaker Use for wood roughing or hogging operations. The chipbreaker is designed to break up chips for fast, clean and efficient removal whilst reducing overall chipload. Compression Spiral Compression spirals are used extensively for cutting double sided laminates. These tools can also be used on natural woods where edge finishing is a problem with standard spiral tools. This tool will leave a clean edge cut.
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29 Tool and Collet Maintenance General Recommendations Tools should be changed at the first sign of edge deterioration causing finish degradation or increase in operator effort to maintain feed rates. Never allow the tools to dwell in a cut. The router bit should be fed in such a manner so that in moving through the work, it has a chance to bite or cut its way freely. If the feedrate is too fast, strain and deflection will occur. If fed too slowly, friction and burning will occur. Both decrease the life of the router bit and are common causes of breakage. The router spindle must be well maintained for any cutting tool to perform properly. Routinely check the collet for wear. Inspect tools for collet marks, indicating slippage due to wear or dust build up. Check spindle on a dial indicator for run-out. Collet and run-out problems cause premature tool failure and associated production difficulties. Do not use adaptor bushings to reduce size of the collet on a routing or production basis. Tools will not perform properly in bushings over an extended period of time. Bushings are for prototype, experimentation, test and evaluation and not for production. Wherever possible, use a coolant when routing. Heat buildup caused by action between the tool and workpiece will lead to premature tool failure. Heat is a function of surface area per unit of time, thus, the more dense the material, the faster the feed rate to minimise heat. However a compromise must be reached between finish and heat.
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  • Fall '19
  • Tools
  • Día, Orders of magnitude, Flute, Tungsten carbide, Collet

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