Bridgeport Boss Success

[PFM Dave]

Success!

So it has taken a while... 2.5 years to write this story as I needed to make this a real success story. So I retired from my JOB and started phase 2 of my life. Part of that was my desire to have a real CNC Mill. I found one local to me on Ebay a Bridgeport Boss, still no idea how old this machine is but I know it had a paper tape in the control box, it was heavy and looked cared for even if it had nor run in some 12 plus years. A deal was struck and we got it to my place. I purchased new Leadshine Stepper drivers with the intent to start with the old steppers. Well it ran!!!! Lots and lots of research and some prior experience with PC based gear led me to Centroid Acorn. Stripped the existing controls and power supplies as others have done and layed out the enclosure for controls, VFD, circuit protection and wire management. Bench tested the hardware and scored my first win. Installed the enclosure and wired up the existing stepper motors to the new drivers and Acorn board. Purchased a good used PC off Ebay and away we went. Watched Marty on Youtube and got the turns ratio pretty close, installed inductive “limit / home” switches and had a running machine! Next day I had the Acorn fail to start! What? How? Read such good things. My next let down was no real warranty for the CPU board, purchased a new CPU from Jameco loaded the firmware and have not had a single Acorn problem that was not related to operator error since.

I was not satisfied with the original 30 something year old stepper motors so upgraded them as reasonably as possible. Lets face it the machine had not made me a dime yet. Installed new Leadshine NEMA 34 stepper motors, lucky for me with a 5/8 shaft size. And now I really had a running machine! Well it had a little bearing noise but the run out in the spindle was OK, run it. Well advance the clock a few years and a few projects and the machine has turned a profit! It was still a little slow, 60 IPM rapids, spindle at 3000 RPM sounded bad. Time for an upgrade!

Purchased new spindle bearings from MATCO, very nice people, new closed loop stepper motors and drivers from Leadshine, ES-MH234120 Motors, ES-DH1208 controllers and cables. And a new motor pulleys from Surplus Center. I am dropping names not because I get paid but shout out to good companies that help.

What are the end results???? Well bearing noise is gone, spindle run out .0001, literally between two hash marks. Spindle max speed of 5000 RPM and smooth. Table motion and control as I have never seen on a big old iron like this... 140 IPM rapids and returns to zero every time. Went with the default of 4000 steps per revolution, fault condition monitored by Centroid.

Only made a few chips today but it is now the success story I wanted to put up on this board. I have a lot to learn and many more projects to build. Now to learn G54-G59 so I can put my two vices to work.

Big thanks to Keith and Marty for making learning a visual experience as well. I learned a bit about machine tools at 15 years old, converted a mill drill to dos based CNC in 1991 and now I have something a bit more serious and I did not take a second on my house to get here.

Regards,

PFM Dave

[martyscncgarage]

Great work Dave! Glad you found the resources that helped you along...
Marty

[PFM Dave]

Rapids are now at 175 IPM for X and Y, I cannot control the 5" Z that fast....

Now for next project...

PFM Dave

[cnckeith]

right on! love those old boss machines.
thanks for posting always nice to hear about you'all getting things running.
did you have a photo album link to include so we can see it?

[dirtydaveMO]

Great job. Pictures would be nice. I am working on an old Bridgeport too. I have stripped all the old electronics and ordered a 1712.oz.in Closed Loop Stepper Motor Nema 34 and Acorn controller.
Dave