where do you call Home

Don Baer

Moderator
Staff member
other than where you hang your hat where do you call home on the Z Axis. I am putting the home limit switches on the machine and the Z axis is got me a bit puzzled. the X and Y I am setting up as all the way left and forward but the Z I am having a hard time with. I want to say all the way up. So where do you hang your hat.
 

Brent Dowell

Administrator
Staff member
Messages
14,921
Location
Reno NV
I home the z axis using a little metal puck and an alligator clip. I have that connected to the z min end stop.

So when I home the z, I put the bit in the spindle, the alligator clip on the bit, and run the homing cycle to min. The z axis goes down until the connection is made.

The thickness of the puck is deducted from the position.

You can either home to the spoil board or the top of the work piece surface. When creating the tool paths in Vcarve at least, you can specify if you want the z=0 to be the top of the workpiece or the top of the spoilboard.

I'm sure the more experienced guys will chime in if I got something wrong.
 

Don Baer

Moderator
Staff member
I home the z axis using a little metal puck and an alligator clip. I have that connected to the z min end stop.

So when I home the z, I put the bit in the spindle, the alligator clip on the bit, and run the homing cycle to min. The z axis goes down until the connection is made.

The thickness of the puck is deducted from the position.

You can either home to the spoil board or the top of the work piece surface. When creating the tool paths in Vcarve at least, you can specify if you want the z=0 to be the top of the workpiece or the top of the spoilboard.

I'm sure the more experienced guys will chime in if I got something wrong.
I have a seperate input for that. The board I have has an input for homing all three axis so you can just tell all the axis to go home. Like for a tool change. then after the tool is in place you can move to the work piece and do the zero operation with the probe. On my board there are 4 inputs.
In 1 - E Stop
In 2 -, Axis Over travel limits
In 3 - axis home limits
In 4 - Z probe input.
 

Bill Arnold

Moderator
Staff member
Messages
7,778
Location
Thomasville, GA
Ditto on Brent's post for me. I do not use a 'home' position for X & Y. I use the center of the work piece as my starting point, then zero Z as Brent described.
 

Darren Wright

Administrator
Staff member
Messages
16,574
Location
Kansas City, Missouri
Yeah, pretty much the same here, especially with two sided pieces, prefer a center datum. I guess for parking the spindle, it's left and front, then the spindle is about 5" high on the old cnc.
 
Messages
155
Location
Emporia, KS
It seems like there is a confusion of terms. When I was teaching CNC eons ago, home and starting point/position were two different animals. Home was left front with the spindle up for tool changes and end of program. Starting point/position was where you zeroed x, y, and z.
 

Leo Voisine

Member
Messages
3,824
Location
East Freeetown, Massachusetts
Machine home is a point where the MACHINE zeros out. VERY VERY VERY common. All machines I have ever worked with have a MACHINE HOME or MACHINE ZERO. That includes Mach3

Where you set your WORK zero is called an OFFSET. It is the distance away from MACHINE zero. G54 is an OFFSET amount in X, Y, Z. Same with G55 and so on.
 

Don Baer

Moderator
Staff member
It seems like there is a confusion of terms. When I was teaching CNC eons ago, home and starting point/position were two different animals. Home was left front with the spindle up for tool changes and end of program. Starting point/position was where you zeroed x, y, and z.
Machine home is a point where the MACHINE zeros out. VERY VERY VERY common. All machines I have ever worked with have a MACHINE HOME or MACHINE ZERO. That includes Mach3

Where you set your WORK zero is called an OFFSET. It is the distance away from MACHINE zero. G54 is an OFFSET amount in X, Y, Z. Same with G55 and so on.
thanks guy for confirming what I thought, I was just over thinking things. I guess because of the shortage of the few part I need to get this ting finished I have waaaaaaaay to much time on my hands.
 
Top