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● CNC-300 X axis position change (second keyway with a shift

Ans:
Regarding the original X axis position change  after one workpiece  processing

According to your report the first workpiece has correct key way after processing but second has key way with a shift 1.5mm on X axis, Normally while you turn on power , controller will ask you to execute zero return (Home) , After you finished Zero return (home) process, The controller will use the Home position as machine zero position (X0, Y0, C0)  , Before you turn off power , the controller will memory The position as zero point and program follow the zero position to move first X and first Y point ,.

Please understand that the controller system use Delta servo motor which position was not memory in servo driver , The X axis servo motor zero position must get after perform X axis Home process , It’s not absolute type servo motor which position memory in battery , Please explain it to your customer.

Besides if the controller battery problem , Controller will issue the battery lacking power , Usually the controller battery have long life and it will charge after power on , If the controller lacking power and you don’t solve the problem , It should loss all parameter , not just X axis , So we think it’s not battery problem.

Usually there is one possible reason to happen the X axis shift problem after execute X axis Home process , while you execute X axis Home  , the X axis Home sensor get signal at 97% ,  then controller warning you signal not within 20-80% and issue alarm then you need to adjust X axis sensor, After adjust if you adjust to nest 50% position , It’s possible shift one pitch 5.0mm (X axis pitch: 5mm) , at the same time controller will issue warning X axis Home position was change.   Your situation is 1.5mm , For controller control principle is not possible.

In our experience , sometime operator use unstable clamping fixture or the fixing position is not same between first and second and third workpiece, So the workpiece center change , so keyway shift , It’s cause by CNC system , it’s cause by fixture not clamping stable problem  , You can ask your customer install two dial gauge , One is touch workpiece outside diameter , Another put on X axis slide , Then you execute X axis home process , then check the two dial value is stable or not  , Then you ask operator to change another workpiece then clamp well then check the sensor touch workpiece is with same value or not , You can take out workpiece and change another workpiece then clamp again , Then check dial position , Maybe you can find the reason which cause the 1.5mm shift . 

Please ask your operator to out a dial gauge while first keyway slotting processing , then change second workpiece then execute slotting process then check dial gauge again , If dial gauge on X slide  with same position  , But dial gauge for workpiece OD wrong  , it mean fixture clamping problem., If dial value for x axis slide which first and second with 1.5mm difference , It mean CNC problem , then take a video for us , until now we never have the kind problem.

Solution:

  1. In our experience, it’s possibly caused by fixture not clamping stable problem  , Ask your customer install two dial gauge , One is touch workpiece outside diameter , Another put on X axis slide , Then you execute X axis home process , then check the two dial value is stable or not
  2. If dial gauge on X slide  with same position  , But dial gauge for workpiece OD wrong  , it mean fixture clamping problem. If dial value for x axis slide which first and second with 1.5mm difference , It mean CNC problem , then take a video for us.