Tool Length Sensor (Breaks tool)

When it lowers the z for the second time do you still have the sensor still in place?
It normally comes down quickly on the first pass then backs up a little then comes down slowly for a more accurate setting.

Taylor,
Yes the sensor is kept in place. It is my tool broke on the sensor actually.
It found a few youtube movies where I saw how it works. But to be honest, I didn't notice the second routine for accuracy.

Hi,
I had the same problem with the macro from Stepcraft. Rory from StoneyCNC sent me a simpler macro that worked straight away.
If you message him I’m sure he’ll help you out.

Hi Cpt Wingnut!
Thanks for your reply. I will contact StonyCNC. Although I think stepcraft should edit the macro so it works for everyone. Show poor final testing to what they deliver.

Hi Cpt Wingnut,

If you are still having difficulties, let me know and I will post my M31 macro on this forum.

Peter

Hey Mathieu,
I agree. The Stepcraft macro does a sort of ‘double dip’, but on the second ‘dip’ just crashes into the sensor. The macro I received from Rory does away with the second ‘dip’.

Hi Peterg1000,
Thank you for the offer but I’m all good now.

Hi Peter,

Ik still don't have the macro. Van you send it to me?
Thx

Hi,

Attached is my M31 macro. Medium speed approach followed by a small retract and a very slow second approach and a larger retract to a stop. When calibrating don't use a real tool, a short piece of metal rod will do just as well. This macro will NOT be suitable if you have a tool changer fitted.

The following line of the macro will need to be edited to enter the height of your sensor - the "32.60" is the height of mine when contact is broken :-

"double newZ = 32.60; // The new Z DRO value after probing and calibration "

After probing, execute a "Goto Zero" - the tool should JUST touch the workpiece. Best to make this value relatively small to start with and then refine it gradually. You can use an electrical contact method to detect the contact, and with care can set the height to within 0.025mm if the height sensor triggers consistently at the same Z value.

Peter

Hi Cpt Wingnut,

I'm having the same issues with the Stepcraft M31. Can you post the macro from Rory please?

Hey Greenwood,
This macro has a single 'dip', unlike the Stepcraft double 'dip'.

I do not remember wher i downloaded my macro but it works good.

The difference to the one posted from peter is that it checks for homing first. I noticed that you should always perform a home before the first time you use the tool.

My macro follows, i changed the "double newZ =" to 32.75 instead the original 32.45 as this worked better after some checks.

//M31 probing macro

double Zmin = -100; //Max.Z depth
double FeedrateFast = 300; //Feedrate for probing
double FeedrateSlow = 40; //Feedrate for probing
double SafeZ = 100;
double retractheight = 10; //The retract height
double retractforsecondmeasurement = 2;
double newZ = 32.75; //The new Z DRO value after probing 32.45

bool dodualcycle = true; //Do probing from 2 cycles, first with Fast and second with Slow feedrates

if(!exec.GetLED(56)||!exec.GetLED(57)||!exec.GetLED(58)) // If machine was not homed then it is unsafe to move in machine coordinates, stop here...
{
MessageBox.Show("You need to home the machine first!");
exec.Stop();
return;
}

while(exec.IsMoving()){}
exec.Wait(200);

double Xoriginalpos = exec.GetXmachpos(); // Get the current machine coordinates
double Yoriginalpos = exec.GetYmachpos(); // Get the current machine coordinates

if(dodualcycle)
{
exec.Code("G31 Z" + Zmin + "F" + FeedrateFast); // Do the Z probing with Fast feedrate first
while(exec.IsMoving()){}
exec.Wait(200);
exec.Code("G91 G0 Z" + retractforsecondmeasurement);
exec.Code("G90");
exec.Wait(200);
}

exec.Code("G31 Z" + Zmin + "F" + FeedrateSlow); // Do the Z probing again with Slow Feedrate to get a more accurate reading
while(exec.IsMoving()){}
exec.Wait(200);

exec.ChangeaxisDROvalue(2, newZ.ToString()); //Change the DRO value
exec.Wait(200); //Safety wait for the UC100 syncronisation

if(!exec.Ismacrostopped()) // If tool change was not interrupted with a stop only then validate new tool number
{
double Zup = exec.GetZmachpos() + retractheight;

if(Zup > SafeZ)
{
Zup = SafeZ;
}
exec.Code("G00 G53 Z" + Zup); // Move 10mm above probe plate
while(exec.IsMoving()){}
exec.Wait(1000);
}

Has anyone used a 1/8th inch flat alum plate for zeroing the z axis?
Also, does anyone have a script that omits the homing of the machine?