X axis hard limit fault

[simjim33]

I have a problem with my X axis settings.
I set my travel on the X axis to be -80mm
I now have homing working as expected. the machine homes and then comes 2mm off the sensors.
I want to set my tool hight system up. The only mounting Point is - on the axis from the home point.
So I try to jog off the home (0) point to find the values for the set up for the tool hight.
I get a X axis Hard limit Alarm at -4mm. This should not be possible at all. Should it?

Nothing is stopping the axis physically
Please advise a solution.
current core firm ware v1.26 current firm ware v3.39.

Thanks



Simon

 

[pinoy-cnc]

Quote from simjim33 on May 28, 2019, 12:53 pm

I have a problem with my X axis settings.
I set my travel on the X axis to be -80mm
I now have homing working as expected. the machine homes and then comes 2mm off the sensors.
I want to set my tool hight system up. The only mounting Point is - on the axis from the home point.
So I try to jog off the home (0) point to find the values for the set up for the tool hight.
I get a X axis Hard limit Alarm at -4mm. This should not be possible at all. Should it?

Nothing is stopping the axis physically
Please advise a solution.
current core firm ware v1.26 current firm ware v3.39.

Thanks



Simon

hi simon,



go to F1

under general setting

disable the hard limit

hope it will help..



Rex

 

[simjim33]

Thanks Rex for you reply.

doing that though will lead me to ask more questions.

like why is it happening in the first place.

Im not too impressed with a machine that has to have fumctions turned off to get it to basic function. (Like backlash, door sensors need a unused input to by pass the lack of them being there)

If you set workable parameters and the machine faults for some reason that s a problem.

Hard limits should work to stop damage to the machine. They are a important safety feature.

Again thank you for the reply but I want to know if my Masso is faulty.

 

[masso-support]

Hi Simon,

I see you are running older software and if it is the result of a software bug then it might have already been fixed.

A new version 3.41 came out today so you could try that and see if it fixes your issue.

If it doesn't fix it can you send a copy of your settings file.

I can't picture your setup but does the X axis travel over the limit switch when moving to the tool setter?

Cheers

Peter

 

[simjim33]

Hi Peter.

There are no limit switches on the machine. Only home points. Induction type.

How do you send a copy of the settings file?

The tool setter is minus from the home piont.

 

[simjim33]

In my view this is a parameter error inside the masso.

 

[broken_ghost]

I had a similar issue but it was to do with how you set up the x axis in masso. In the axis settings page you need to set the home to where the switch is not 0, so if you have -30 travel you need to set the home to 30 so the masso knows it can travel beyond the switch, then it will hit the soft limit after that at 0. at least that fixed the issue for me

 

[simjim33]

1That s interesting. Thank you for that I will try that next. Just to be clear do you mean the homing axis screen?

Because I don t recall anything on the axis screens in relation to homing.

That seems a easy fix.

I wonder why that is the case ?

Maybe my logic is wrong in this case but it s worth a shot.

I would never have seen that.

My mind says. Set your axis parameters first.

Then set up the home function as the axis already knows it s limits.

If this does work, I spent a morning moving a home switch I didn t need too.

Just looked at the manual again. I can understand my confusion.

 

[masso-support]

Hi Simon,

For your machine settings file.

Just go to the F1 screen then under Save & Load Calibration settings click [Save to File]

You will now find a file called MASSO_Settings.htg on your USB stick.



The homing inductive sensor is your limit switch and so long as your axis does not pass over it in its travel then you should not get a hard limit tripping.

I use the same sensor type that you have but can't use the hard limit on mine, and have it turned off, because my X and Z axis will move over the sensor before it reaches the extent of it's travel.

It isn't a problem because I am using soft limits which keeps the axis in bounds after homing.

I think most people turn them off and rely on soft limits.

With soft limits the axis can pass over a sensor and will still stop the axis before it reaches the extremes of its travel. Mine moves to within 2mm of the ends and stops on the X & Y and right to within 1mm of the top on the Z.


For hard limits to be effective you would need sensors at each end of the X and Y axis otherwise you only have a hard limit at one end of the travel and it will crash at the other end.

They must also be at the extremes of travel.

I plan to make a homing / soft limit video setup video in the near future to help with the setup process.


Hope this helps

Cheers

Peter

 

[simjim33]

hank you for the reply Peter.

I will try that now I'm back in the shop.

One question though. If the machine hasn't got absolute encoders on it. will it store the last portion in a memory file?

If the machine gets turned of where it finishes. how exactly will the machine know which way to travel to home. at it seams to me all distances are relative to the home point. unless you stick your home point in the corner. you will have a problem.

I don't want to put my home point in the corner as i want to be able to open the doors and change a tool. Then close the doors and tell the machine to auto zero the tool.

Does that make sense?

 

[simjim33]

Update.

Thanks to Rex and Peter.

Disabling hard stops works.

Im not really impressed with that config.

Im not to sure about having to have the home piont at a corner.

But this allows me to get the the tool setter so I m happy for now.

Next thing to do is sort this wonky ball screw out,

yep I have a wonky screw.

 

[breezy]

Quote from simjim33 on May 30, 2019, 2:28 pm

I don't want to put my home point in the corner as i want to be able to open the doors and change a tool. Then close the doors and tell the machine to auto zero the tool.

Does that make sense?

Our setup has the home point in the rear right corner, tool zero set in the front left corner at X,Y zero, but the WSC is X=200, Y=10 set in G54. Tool change position is set to X=700, Y=20 which is in the middle of the front edge.

Check this page Manual Tool Change

Regards,

Arie.

 

[simjim33]

That s interesting.

will it move to the last work position and then go off to auto hight tool then restart work.

I was going to set a G5# and insert that call in post.

Can it be done with a M6? ( tool change call?) so I don t have to set the post.

 

[breezy]

Sequence of events with auto tool zero enabled

• Start MASSO.
  
• Home machine - machine homes & sets tool length. Stops at ATZ point.
  
• Start program.
  
• If tool required is in machine - it starts cutting.
  
• If not goes to
  • Tool change position.
    
  • Change tool - press start program.
    
  • Sets tool length.
    
  • Goes to last position
    
  • Starts cutting.
    
  
  
  

Last 5 operations occur on each tool change command.

Regards,

Arie.

 

[simjim33]

Thanks Arie.

so no need to write that all into the post then.

Interesting.

Maybe I won t have to move the home piont again.

 

[masso-support]

Hi Simon,

In answer to your previous question about Masso using the current machine coordinates to figure out which direction to move to find the home switch the answer is no it doesn't.

By definition asking to home the machine is basically telling it that it is lost so it simply moves in the direction setup in the homing section on the F1 screen. When it finds the switch it will stop, back off and set the coordinate to the value you tell it on the Homing page. If in an extreme case you put the homing sensor in the center of the axis and start homing on the side of travel the machine will crash because it will not find the switch. This is why it is important to put the switch as near the end of the axis as possible and so long as you always start homing on the correct side of the homing switch you will be ok. Mine are within an inch of the ends so it isn't really a problem. Since my homing switches are within the area of travel and will trigger before I get to the end I have to turn off hard limits. The good thing is because i'm using soft limits the axis will move to within 1 mm of the ends and not crash.

I hope this helps

Cheers

Peter

 

[simjim33]

Hi Peter.

yes I understand that.

Machines I have used have had absolute encoders. So maybe I m just a bit spoiled.

Its fine I can work with what is now working.

thanks for the help.



Simon