[forhire]

At present my Bridgeport TC3 with the DX-32 control always homes the table under the tool carrousel. I have a job that requires a very tall fixture and some long tools. Looking at the arrangement I'm sure homing under the carrousel will prove disastrous. I know I can set my clearance point at the far extreme so I'm fine on tool changes but when I home everything on power up it's going to drive the fixture into the tools. How can I reverse the homing direction and/or set new home point? I poked through the setup but didn't find what I need.

[alastairseggie]

Hi Forhire

I am by no means an expert on CNC machines but, from an electrical/mechanical point of view I cant see how it would be done short of moving the home switches or trigger blocks. when the machine homes it has to go to a known physical point on the machine to take its reference. You might be able to start up then home the machine then park it at the far end of the table while you set up. Then machine. all the time keeping the machine on and homed.

Alastair

[forhire]

I am by no means an expert on CNC machines but, from an electrical/mechanical point of view I cant see how it would be done short of moving the home switches or trigger blocks. when the machine homes it has to go to a known physical point on the machine to take its reference. You might be able to start up then home the machine then park it at the far end of the table while you set up. Then machine. all the time keeping the machine on and homed.

There is a limit switch at each end of the axis. I poked around in the setup and it appears I can reverse the trigger order it but obviously I need to reverse some of the axis measurements. This is where my limited knowledge derails. I was hoping someone on the list could shed some light as to all the edits that would be required.

I have it sorted for this go around. I had to modify my fixture a bit and mount it at the far extreme. I have an inch x axis clearance so I'm safe.

[alastairseggie]

On My R2E3 there are 2 switches per Axis (X and Y.....Z has 3) These are in a single housing. Then there are 2 limit and 1 Home metal stops that trigger the switches. on the X the one closes to the machine is the Home and the furthest the limit. see pic

http://flic.kr/p/fN35at

The home switch is only used for homing and is in a different circuit from the Limit switches which are part of the emergency stop Circuit. You would need to both move the home switch the metal stop and tell the machine that it has homed at say 18,0,0. I cant find any command or mention of being able to change the Home position in the manuals I have.

Perhaps I am missing something

[greggv]

there has to be something written in the homing routine that tells the motor to go cw or ccw. You may have to move the home limit switch, but you're going to have to change something in the executive program to reverse the motor's rotation when homing is called for.