Dual limit switches ???

Am upgrading a Bridgeport Series 1 CNC to EMC2 after removing the old BOSS 5.

Everything is proceeding fine, but opened up the Z head wiring box to rewire the limit switches from NO to NC.

Discovered to my surprise that there are three limit switches for the Z axis. Research in the Bridgeport maintenance manual shows that there are two micro switch type switches, operated by ramps, and these are supposed to be set 0.040" from the end of travel. In addition, there is a plunger type switch which is the upper limit switch, and should be set to 0.020" from the end of travel.

The book refers to the upper micro switch as a "deceleration switch", presumably to warn BOSS 5 the the upper Z limit is near.

Any idea how to feed these two upper limit switches to EMC2 ? At this point, I'd planned to put all limit switches in series and use the limit switches as home switches also. Now I'm baffled.

Project info: tomwade.me/tw/machinist/nm/

Tom

Thanks, John.

One more quick question. Been trying to find an elegant solution for telling the lube pump to turn on. I have four solid state AC relays mounted, one each for flood, mist, and vacuum cleaner (shop vac, for cutting wood, etc). Just occurred to me to use the eStop + to turn on the spare relay to send power to the lube pump.

Does that sound like a workable plan?

Tom

BigJohnT wrote:

On my lube pump (air spring type) I used motion to trigger a timer in classicladder. This way when there was no motion there was no lube dripping all over the place.

I'm using a Tiwanese clone of the Bijur pump, which gives one shot of lube every 30 minutes. If I find I'm getting too much lube (sure don't want too little lube) I'll use the motion idea to turn the lube pump on..
What would be the connection for motion to a pin?

Flood and Mist are connected to an output pin on your breakout board and inside of EMC you connect iocontrol.0.coolant-mist and flood to your physical pin.

What are you using for your I/O into the PC?

BTW, nice score on the mill.

John

Using a PMDX-132 for primary I/O, with a PMDX-107 as a speed control for the spindle (vfd). Unfortunately, I'm out of I/O pins, so need to order either a PMDX-122 or C1 or similar for a secondary I/O.

Thanks. I'm loving having it. Was looking for something a little bit bigger than the Sherline, and discovered that the Bridgeport filled that niche quite well, and was (I thought) going to be less money. it'll end up being slightly more money, but it's a bunch more machine.

Tom

BigJohnT wrote:

You will find out real fast that the real money is in tooling... I use flea bay for my kwik switch 200 tooling and Maritool for my BT30 tools.

John

I found a good source for tooling holders, a guy out in Oregon who buys truck loads of surplus stuff to get a few holders for himself, then lists the rest for sale.

www.tools-n-gizmos.com/