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--- tools:cnc_router:tuning [2023/09/24 15:56] – removed - external edit (Unknown date) 127.0.0.1
+++ tools:cnc_router:tuning [2023/09/24 15:56] (current) – ↷ Page moved and renamed from tools:cnc_router_avid_pro_tuning to tools:cnc_router:tuning smartin015
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+====== Avid Router for Accuracy Tuning ======
+TODO.  I think the acceleration settings need to be adjusted down as I'm getting some ringing when transitioning from X to Y moves.
+===== TLDR =====
+The testing below I arrived at the following:
+  * X Steps per Inch: 2037
+  * Y Steps per Inch: 2040
+  * Z Steps per Inch: 5080
+  * X Backlash: 0.0075
+  * Y Backlash: 0.002
+  * Z Backlash: 0
+  * X Acceleration: TBD
+  * Y Acceleration: TBD
+The defaults I found where 2038 for X and Y and 5080 for Z.  0 for backlash.
+===== Setup =====
+I found a 3 steel 5 sided box box under the welding table.  I used a large kreg C clamp to clamp it down to a clean part of the spoil board at the front right and it was surprisingly sturdy.
+This will be the platform in which I use digital calipers to measure distance traveled over 5 inches with an accuracy of 0.0005"    And a dial indicator where you can inference down to 0.0001"
+===== Calibration =====
+==== X Axis Travel ====
+  * Mounted the box with the open side to the front
+  * Mounted calipers off the left side of the box with a spring clamp clamping the bottom jaw to the box allowing the top jaw to move freely.
+  * Extended the caliper to near it's full extent.
+  * Jog the router so that the mounting plate is to the left of the calipers and would push the calipers closed if moved to the right.
+  * Slowly jog the spindle to the right with the pendant until it starts to close the calipers.
+  * Zero X axis and zero calipers.
+  * go to MDI so that you can enter Gcode.
+  * ''G1 X-1 F80'' Move the machine to X -1 at 80 IPM
+  * Extend the calipers to near it's full extent again so that it's reading >0
+  * ''G1 X0.0000 F30'' Move the machine back to 0 slowly.   I noticed that if I didn't specify 0.0000 it would be ok with stopping at +-0.0005 as reported in Mach 3.
+  * Verify that the calipers read 0.  If there is variation try to fix the measurement rig so that you get consistent results I was able to get it to be consistently at half a mil.  0.0000 - 0.0005
+  * After you're confident in the setup lets do the x distance measurement.
+  * ''G1 X5.0000 F30''  This will move the spindle to the right and close the calipers by roughly 5 inches.
+  * Record the measurement ie ''5.005'' so it moved 5 mil more than it should have.   Do the test a few times to make sure you are getting consistent results.
+  * Go to the config menu in mach 3 and pick motor tuning.
+  * Look at the steps per inch in the bottom left of the window ''2038''
+  * Determine the distance per step ''5.005 / 2038 = 0.0024558390578999''
+  * Determine the number of steps to travel desired distance ''5 / 0.0024558390578999 = 2035.964035964038''.  Round that to a whole number, 2036.
+  * Update the steps per inch in Mach3 and test again. However I found that this number over corrected and needed to land on 2037 for best results.
+==== X Axis Backlash ====
+Backlash is the term for the slack in the gear teeth, or belts when changing direction.  I.E the difference measured when when travelling to a point when going to that point from the left and from the right.  To test this we will use a dial indicator.  It would be possible but tricky to do it with calipers.
+Attach Magnetic indicator arm to the steel box. and arrange it so that the spindle mount will be able to depress the indicator probe when moved to the right.
+  * Use the pendant to slowly jog the spindle to the right until the indicator has started to be depressed
+  * Zero x axis and zero the indicator
+  * Now test for repeatability by going to -1 and to 0 a few times
+    * ''G1 X-1 F80''
+    * ''G1 X0.0000 F20''
+    * If there is variability of more than 0.002 try to see if you can find the cause. It may be in the measurement rig.
+  * Move to the right, but don't crash the indicator. then back to zero from the other direction.
+    * ''G1 X0.3000 F20''  move 3/10 of an inch.
+    * ''G1 X0.0000 F20''  move back to zero and observe how far it is from 0
+    * repeat the sequence.  to to -1. then 0 then .3 then 0 and make sure all numbers are consistent.
+      * ''G1 X-1 F80''
+      * ''G1 X0.0000 F20''
+      * ''G1 X0.3000 F20''
+      * ''G1 X0.0000 F20''
+  * I observed a backlash of 0.0075"
+  * Under config open Backlash. and put the measured difference into X backlash and check the enable option.
+  * It says a restart is needed so click on config, save settings.  close and re open mach 3,  reset, and try the test above and see if it corrects for the backlash.
+==== Y Axis ====
+I used the same methodology as above I just needed to re-clamp the steel box so the open side was to the left.
+=== Z Axis ===
+For this one with the limited move I used the indicator to measure distance too but the machine was spot on for both travel and for backlash I didn't need to change anything.
+===== Acceleration =====
+I've seen ringing a few times on profile cuts on direction changes.  In the motor tuning section there is the ability to lower the acceleration settings   I still need to come up with a method to tune that.   would like to be smarter than doing a bunch of test cuts but I'm not sure.