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● CNC-300 How to check the cutting result (why can't cut material well)

Ans:


Regarding the possible reasons causing you can’t cut the material well.

  1. The both side don’t grind symmetry , Besides if the right corner of cutter was dull , It will cause right side cutting sharp edge can’t cut material , The dull cutter body touch the work piece before cutter edge cut the material , It will cause cutter can’t cut material smoothly because cutter touch inner hole at dull surface, Please understand that you must use tool grinder to sharpen the slotting cutter well , Don’t use bench grinder to hand grind  the slotting cutter ,  Attached is the standard slotting cutter photo for your reference.
  2. Regarding the slotting sound and cutting chip , The problem cause by :

    a)  Both side not grind symmetry , cutter right side is dull , Not sharp , Relief angle grind not well  etc..
    b)  If  cutter is too short and cutter install over slotting bar tool long , Usually the cutter edge over slotting bar as short as better because rigidity reason , Normally , the cutter edge over (out side length) slotting bar hole is “Keyway depth +1-2mm “.
    For example , keyway depth 5mm , The cutter set over 6-7mm long from slotting bar OD surface , If operator set cutter 15mm long over slotting bar and cutter body only 15mm-20mm ,  It will cause the cutter not stable , The cutting edge sway (rock) during cutting process and the cutter can’t cut material stably due to cutter rigidity is bad.
    , Need to correct length (6-10mm cutter total length must have 40-50 mm , Cutting edge not over 8mm) , If you need longer (Over 10mm)  , You need add support block at cutter top position to add the cutter rigidity.

    Besides, If setting the 1st point X at 2.2  , the other side is X value is -1.8  , It mean you don’t set your work piece at  rotary table center , If to freedom to install the chuck on rotary table , Do you align the slotting cutter to parallel to our X axis or parallel cutter body to parallel to our feeding Y axis.
    If cutter edge not sharp or install not alignment  , It will cause dull cutter surface to touch the material ,  Then it will cause the bad slotting result  .

  3. Besides, If setting the 1st point X at 2.2  , the other side is X value is -1.8  , It mean you don’t set your work piece at  rotary table center , If to freedom to install the chuck on rotary table , Do you align the slotting cutter to parallel to our X axis or parallel cutter body to parallel to our feeding Y axis.
    If cutter edge not sharp or install not alignment  , It will cause dull cutter surface to touch the material ,  Then it will cause the bad slotting result  .
  4. Following is to teach you how to check the cutting result , If the cutter edge is with good sharpen process and set at correct alignment position , and cutter material is good such as ASSAB 17 , SECO (Hardness HRC67-69)  HSS-CO8 or CO 13  , and material is pure material ,  The slotting chip will be like roll shape chip , If the slotting chip is break shape,
    Below points for you to check :
    a) Cutter grind no good
    b) Material is not pure material such as tube material
    c) Material too hard (Hardness over HRC25 and your cutter can not cut the material smoothly 
    d) Cutter not alignment well to cause cutter body touch inner hole then cause dull cutter can’t cut inner hole well.