Tool life is affected dramatically by tool geometry Rake and clearance angles

Tool life is affected dramatically by tool geometry

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Tool life is affected dramatically by tool geometry. Rake and clearance angles, as well as cutting edge length should be examined. Router bit breakage is most often caused by a misapplication of the router bit. Do not assume the proper router bit is being used.
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2 30 Fitting Tools into Collets and Spindles Note: To ensure trouble free operation, always insert the collet into the collet nut until it clicks in and thread it loosely onto the spindle prior to inserting router bit. Collet Maintenance Collet maintenance is one of the most common causes of inadequate tool life or breakage. There are many factors, that can affect this critical tool holding system called a collet. As a chain is only as strong as the weakest link, a router bit can only be as good as the system that holds it properly. The small amount of time spent to regularly inspect and clean the collet system, will be more than offset by increased productivity and a reduction in overall costs. 1. Make sure you have the right size collet for the tool to be used. Push the collet into the nut until it clicks into position. Insert collet at slight angle to engage collet groove in locking ring of nut. 2. Screw the nut loosely onto the spindle or toolholder cone. 3. Insert the tool into the collet. The tool should fill at least 80% of the collet bore but do not allow any of the flute run out to enter the collet.
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31 Collet Maintenance 1. Internal Collet Clamping Surfaces The most important link in the tool holder chain is the inside of the collet. Resin migrates up through the slits in the collet and then deposits itself on the inside of the collet. This resin build up, if not removed, causes the collet to grip inconsistently on the tool shank. By not applying equal pressure throughout the entire gripping range of the collet, the tool holder allows the tool to resonate inside, causing slippage inside the collet. Slippage can cause “fretting”, a condition in which resins are deposited on the shank of the tool. Any resin buildup should always be removed from the inside of the collet. 2. Internal Spindle & Collet Taper The inside taper of the spindle and tool holder is a critical surface which accumulates resin build up and should be cleaned at each tool change to maintain best concentricity. Felt brushes are available to fit most taper sizes and provide a quick means of removing short-term buildup. 3. External Collet & Tool Holder Taper The outside taper of the collet and tool holder require regular inspection and should be cleaned of all deposits each time the tool is changed. Brass brushes work well for this application, but felt cloths can also be used if the tapers are regularly maintained and the buildup is minor. 4. Clamping Nut Surfaces The inside of the nut should be clean and free of burrs on the surface. Any surface burrs or contamination will not only skew a collet but can also permanently ruin a new collet. The clamping nut should be cleaned with a brass brush during every tool change. Special care should be taken to examine the clamping nut threads on a regular basis.
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  • Fall '19
  • Tools
  • Día, Orders of magnitude, Flute, Tungsten carbide, Collet

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