Need Help!- Homing and Limits Setup

[Mr.Chips]

Homing and Limits have been set and when I press Reference all Home everything goes home just fine in the picture on the machine. It is a fixed gantry so I wanted home to be in the X-, and Y+ and Z+, this way it would be the easiest to load and remove work.

When the machine has been homed and Soft Limits is activated I can drive the X in the plus direction and the Z in the minus direction, however I cannot move the Y in the minus direction. The only way I can move the Y in the minus direction is to disable the Soft Limits.

I have attached a screen shot of the Homing and Limits setup screen showing the settings; hopefully this will show where the problem is.

[Juka]

Originally Posted by Mr.Chips Homing and Limits have been set and when I press Reference all Home everything goes home just fine in the picture on the machine. It is a fixed gantry so I wanted home to be in the X-, and Y+ and Z+, this way it would be the easiest to load and remove work. When the machine has been homed and Soft Limits is activated I can drive the X in the plus direction and the Z in the minus direction, however I cannot move the Y in the minus direction. The only way I can move the Y in the minus direction is to disable the Soft Limits. I have attached a screen shot of the Homing and Limits setup screen showing the settings; hopefully this will show where the problem is.

What happen if you chance "Y-axis Home Off -27.5" to positive +27.5 ? (second picture)

Juka

[Mr.Chips]

Originally Posted by Juka What happen if you chance "Home Off -27.5" to positive +27.5 ? (second picture) Juka

I changed the Home Off to positive +27.5, and the Reference all Home still works but I can no longer activate the "Soft Limits" button. So I switched it back to -27.5.

Thanks anyway.

[ger21]

Curious why you have it set up so that all the coordinates are negative?

The reason you can't jog in the Y- direction is because you're home position is already at the limit of your soft limits, at -27.5. How far do you want to be able to move (from home) in the Y- direction? If you want to move 10", then change the softlimits to -37.5.

It's hard to tell in the pic, but it looks like if the router mover right along the gantry, that would be X+. Do you have Y- moving towards me in the pic?

[Mr.Chips]

Originally Posted by ger21 Curious why you have it set up so that all the coordinates are negative? The reason you can't jog in the Y- direction is because you're home position is already at the limit of your soft limits, at -27.5. How far do you want to be able to move (from home) in the Y- direction? If you want to move 10", then change the softlimits to -37.5. It's hard to tell in the pic, but it looks like if the router mover right along the gantry, that would be X+. Do you have Y- moving towards me in the pic?

The table is in the XYZ home position now.
The cut area in the Y axis is 27.5". So I want the table to move 27.5" in the - direction.
I added the Axis and direction on the photo. Possibly this will help you.

[Greolt]

It is perfectly reasonable to have the machine hit home switches in the position shown but you have your Y axis pos and neg around the wrong way.

Change that by reversing the Y in "homing and limits"

Then set the "home off" amounts to, X 0 and Y 27.5

Get that right and get your head around it before progressing to setting up soft limits.

Which will be something like X 0-19 and Y 0- 27.5

Greg

EDIT: Oh yeah you also must set the Y to seek home in the positive direction

[ger21]

Yep, what Greg said. I had a feeling the Y was backwards.

[Mr.Chips]

Originally Posted by Greolt It is perfectly reasonable to have the machine hit home switches in the position shown but you have your Y axis pos and neg around the wrong way. Change that by reversing the Y in "homing and limits" Then set the "home off" amounts to, X 0 and Y 27.5 Get that right and get your head around it before progressing to setting up soft limits. Which will be something like X 0-19 and Y 0- 27.5 Greg EDIT: Oh yeah you also must set the Y to seek home in the positive direction

I think I changed it like you suggested see photos, shut Mach down and restarted and with it set like that the Reference all Home still works but I can no longer activate the "Soft Limits" button.

My head hurts, wrapping too much I guess.

Most people use a movable gantry and I have a movable table, like a milling machine, this may be the confusion???

[ger21]

Oops. Moving table means you had it right the first time. Well, almost.


Hold on while I double check this

[ger21]

Set Softlimits Y min to 0 and Y max to 27.5, and Y Home Offset to 27.5

That should work.

[Greolt]

Ok well it is confusing because I read the red arrows on your picture to represent the relative spindle movement and not the actual table movement.

That is the way you must think about it. Imagine the tool moving instead of the table.

Greg

EDIT: and what Gerry said is correct. (which is also what I said) at least that's what I meant

[Mr.Chips]

Originally Posted by ger21 Set Softlimits Y min to 0 and Y max to 27.5, and Y Home Offset to 27.5 That should work.

See configuration pictures.

After changes it still homes OK
And the "Soft Limit" button will light when moused.
The Y will now move off of home with the soft limit light on.
However the X will not move off of home in the + direction, but it will move to the - dir until it hits the limit. I het reset toclear that, and I can move X in the + direction only slightly then it starts singing the soft limit song and stops.

Hmmmm I tried to set these soft switches months ago and gave up, wonder if that wouldn't be the easiest.

Confused in the southern Arizona Desert.