problem size in mach3

[kocher]

hi, can anyone explane please after i put gcode into mach3 itis always reads  wrong size ex if i want square 1in it engraving it gos to  0.940 so i have to  creat square 1.325 in till i get 1 square inch i need your advise please
T1M6
G0Z1.0000
G0X0.0000Y0.0000S15000M3
G0X0.0121Y0.0202Z1.0000
G1Z0.0000F9.4
G1X1.3371Y0.0202F14.2
Y1.3452
X0.0121
Y0.0202
G0Z1.0000
G0X0.0000Y0.0000
G0Z1.0000
G0X0Y0
M30

[Hood]

If you command a 1 inch move via the MDI line does it actually move 1 inch?

Hood

[kocher]

no if i command a 1 in  it will be  0.740 . thank hood  for your help.
 T1M6
G0Z1.0000
G0X0.0000Y0.0000S15000M3
G0X0.0163Y0.0198Z1.0000
G1Z-0.0250F9.4
G1X1.0163Y0.0198F14.2
Y1.0198
X0.0163
Y0.0198
G1Z-0.0500F9.4
G1X1.0163Y0.0198F14.2
Y1.0198
X0.0163
Y0.0198
G1Z-0.0750F9.4
G1X1.0163Y0.0198F14.2
Y1.0198
X0.0163
Y0.0198
G1Z-0.1000F9.4
G1X1.0163Y0.0198F14.2
Y1.0198
X0.0163
Y0.0198
G0Z1.0000
G0X0.0000Y0.0000
G0Z1.0000
G0X0Y0
M30

[Hood]

Then it sounds like you have your steps per unit set wrong.

If you tell me the following info I will work out what your steps per unit should be

Is it steppers?
What microstepping do your drives have? (or make/model if you are not sure)
Do you have any reduction between motor and screw?
What is the TPI or pitch of the screw?


Hood

[kocher]

 the steppers are direct drive. (helical couplers )

  high-precision linear Round rails, diameter 0.8-inch,
     

  The use of high-precision new ball screw, 

there is no rebound in return;  diameter 16 mm; pitch 10 mm;   

  Aluminum alloy T-slot table,  Can help you cut and fixed,
  Manufacture than wood table has a huge advantage,

   NEMA23 stepper motor current is 3A, the weight 2.2 pounds ,Torque 1.7n.m 245 oz.In.

    30v 3A CNC drive,tb6560 , Optical isolation, the maximum 1 / 16 micro-step,Spindle control relay

     400w 30v Switching Power Supply

 spindle motor is  850w, 4 level speed, 5000--30000RPM, Strong power;

  milling tool diameter:  8mm,6mm,3.175mm

Router is the length of 28 inches, width
 thanks  for your  answer

[Hood]

Do you know the microstepping you have the drives set to, it says there that Max is 1/16, is that what you have it set at?
Are your native units inch?
Hood

[kocher]

sorry all i know u did help me to run my machine in past i have this info it may help again thanks for your advise . steps per 760 .velocity 151.98. Acceleration 4. step pulse0 dir pulse 0 .

[Hood]

Ok can you attach your xml and I may be able to work it out from there. With the steps per unit at 760 it would mean from the above info that you are just 1.49 microstepping which doesnt sound right.
Hood

[Hood]

Ok looking at your numbers I am thinking you are at 1/2 stepping so your steps per unit would be 1016, give that a try and see.
Hood

[kocher]

i did put 1016 per step its working  perfect size  thank very much it is  working 100% thank you .