Homing & Hard Limit Switches

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cnckeith
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Re: Homing & Hard Limit Switches

Post by cnckeith »

wire the two switches you have currently connected to input one "homeall" to individual inputs 1 and 2
and set the Wizard input definition as follows.

homelimit.PNG
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
ShawnM
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Re: Homing & Hard Limit Switches

Post by ShawnM »

Dan, I'm a router guy and have no clue how to setup a lathe and which direction or axis is which letter. All I know is that you only need one n/c switch on each axis at your home position, defined properly in the wizard and software limits set properly for the machine to home and not crash. My router is set up with 3 home switches (I have 3 axis) and soft limits set and it hasn't crashed once in almost 2 years. You have your inputs set up as home only, this needs to be changed first.

I'm hoping a router guy will chime in here and help you with the homing and directions of travel as I don't understand how the lathe works with Centroid. I just watched a video made by cnckeith and the lathe was homed at the far right of the bed which is opposite of yours. I know homing can be where you define it but I just don't understand the lathe setup like many others here on the forum.

Again, all I know is that your settings are not correct and this is causing your crash.
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Re: Homing & Hard Limit Switches

Post by ShawnM »

Oops, I was typing my response when Keith posted his response. There ya go.
leinadltd
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Re: Homing & Hard Limit Switches

Post by leinadltd »

cnckeith wrote: Fri May 21, 2021 8:43 am wire the two switches you have currently connected to input one "homeall" to individual inputs 1 and 2
and set the Wizard input definition as follows.


homelimit.PNG
My apologies, just a little confused here. Are you saying to wire the homing micro-switches from the Z-axis and the X-axis into one "series" pathway coming out of IN1 and change the Acorn Input selection to HomeALL? Next, are you trying to say to wire the "limit" switches from the Z-axis and X-axis the same way coming out of IN2 & IN3 respectfully, changing the Acorn input selections to FirstAxisHomeLimitOk and SecondAxisHomeLimitOk respectfully?

-OR-

Are you saying to wire the "homing" micro-switches from the Z-axis and the X-axis into one "series" pathway coming out of IN1 and change the Acorn Input selection to FirstAxisHomeLimitOk ? Then, are you trying to say to wire the "limit" switches from the Z-axis and X-axis the same way coming out of IN2, changing the Acorn input selection to SecondAxisHomeLimitOk?

I am a detail and logical thinking person. Sometimes the long-detailed explanation is better for me to understand, like water flowing thru a pipe system. People's thought process is different and what is communicated might not be what is understood. I await for your reply.

Thanks, Dan
ShawnM
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Re: Homing & Hard Limit Switches

Post by ShawnM »

No Dan, Keith is saying to wire your X axis limit switch to input 1 and wire your Z axis limit switch to input 2. Use the n/c side of the micro switches. Set input 1 to "FirstAxisHomeLimitOk" in the wizard and set input 2 to "SecondAxisHomeLimitOk". These switches will act as a limit switch AND a home switch. Then set your software travel limits to the measurements you stated earlier in your posts.

You need only TWO switches on the machine, no more, no less. One wired to input 1 and the other wired to input 2.

When you first startup the machine you MUST home it first. Then there is no way the machine will crash into itself. After it homes and sets machine zero it will not go past that mark again.

Make sure the homing travel direction is set correctly and also that the software limits are set correctly. Again, I'm not a lathe guy at all so I can't help with how the directions work on a lathe.
CNCMaryland
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Re: Homing & Hard Limit Switches

Post by CNCMaryland »

Lots to read here, but why not just have the switches for homing and then use Soft Limits in Acorn.
ShawnM
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Re: Homing & Hard Limit Switches

Post by ShawnM »

CNCMaryland wrote: Fri May 21, 2021 2:18 pm Lots to read here, but why not just have the switches for homing and then use Soft Limits in Acorn.
That's exactly what we are trying to convey to Dan. All those extra switches and wiring seem like a nightmare when it so simple. All he needs are 2 switches and some wizard programming and he's done.
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Re: Homing & Hard Limit Switches

Post by andyolney »

Dan-
I'm slowly converting the same lathe and love the simplicity and clean look of the direct drive on the x and z-axis. It is much simpler than the belt drive I have been planning. I also have 425 oz-in motors and am curious how well they work in your design. Also what size is the z-axis ballscrew that you have mounted in the original z-axis bearing blocks?

Andy Olney

PS I bet more details would be appreciated by the forum members, I know I would.
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Re: Homing & Hard Limit Switches

Post by leinadltd »

I purchased the CNC conversion kit from Mike Canada from Spring, TX. Send me PM and I will get you the details.
ShawnM
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Re: Homing & Hard Limit Switches

Post by ShawnM »

Dan, did you resolve your issue?
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