Bridgeport Boss3 Questions

[damae]

WooHoo! I just bought a Series I with Boss 3 control! I can't wait to get it in the garage and start cleaning it up!

In the meantime, I have some burining questions:

1. Can I use a VFD to run the whole machine on single phase? Is a phase converter neccessary for that?

2. How much noise does a phase converter make?

3. Can I just convert the machine to single-phase by swapping the spindle motor? In other words, can the Boss 3 control run on single phase? It seems to make sense that it would run on only one leg of the 3 phase.

4. Where can I find suitable single-phase replacement spindle motors? Or would it be cheaper to run the spindle off a VFD. If the spindle motor is the only 3-phase component, then running it off a VFD would essentially convert the whole machine to 3 phase, no?

5. Can I move this thing with a pallet jack? They can load it onto the trailer with a forklift for me. How do I get it off the 18" high deck of the trailer and onto the Driveway? Once on the driveway (on the pallet jack) will it be easy to pull it uphill? The driveway slopes away at about a 1" per foot.

6. Does this machine have ballscrews or acme leadscrews? They were protected with a coiled steel shield so I couldn't see them directly.

7. How much (aproximately) would a ballscrew kit cost?

Any answers to those questions will help me enourmously! Thank you!

[machintek]

Has ballscrews.
T2 transformer is a 3 phase device for the drives.

George

[Zoriander]

but which ballscrews are normal? and how much do they cost?

[damae]

Originally Posted by machintek Has ballscrews. T2 transformer is a 3 phase device for the drives.

Thanks George! So it sounds like I can't run the Boss 3 control off of single phase. Is that correct?

Can anyone answer any of my other questions about moving the machine, VFDs, or spindle motors? Thanks in advance, if you can!

[machintek]

Need to tell you a few things up front. In a 20+ years in field service, most of it BPT related, I have seen less than half a dozen BOSS 3s. Most of the boards are wire wrapped. That means they have long pins and wires wrapped around them instead of a printed circuit boards. These are prone to corrosion and thus bad connections. I do not believe you have RS232 for communications. These machines were talked to in 20ma (milli amp) communications loop. I changed a lot of transistors in this circuit. The outside device was a TYPE 33 or TYPE 43 teletype.
You could rewire the entire machine for single phase but would also need to do something to run the spindle motor. For the effort and time you would need to invest, I would suggest you get a rotary phase converter.
Moving the machine can be accomplished with a forklift or can be rolled around on 1 inch round steel bars. I installed a machine into a garage by having a tow truck meet me there, lift the machine out of a truck with a sling around the ram, and extend his boom inside the garage as far as possible. From there it was the rollers.
My S1STD was removed in pieces from a trailer with an engine hoist. The head, ram, and turret came off as one piece. A strap around the spyder lifted the base, table and knee. Your machine is a lot heavier, and that slope really worries me. Can you roll your car up that incline? The machine ways about the same.
I would have to do some reaearch on ball screws to see what is available. Grab one one of that coiled cover and move it to the side to expose the ballscrew. Unless you need to do precise work, these ball screws may be OK. Remember that this machine moves in .001 inch steps, so that is as close as you will get.

George

[damae]

George,

Thank you again for the good information! Wow, wire wrapped, I haven't seen any of those since I was a kid! (you know, the Radio Shack kits).

Do rotary phase converters make a lot of noise/heat?

I'm told the control on my machine was acting somewhat flaky. Now I have a prime suspect in what's causing it -- the corroding wire wraps. On the other hand, it could have something to do with the 50 pounds of chips packed in between the control boxes and the base of the machine. Hehe. They are packed in there right up against the side of the cabinets where all the air vents are. I was thinking that some chips just made their way onto the board and intermittently make contact.

I bought the machine with the idea that I could limp the control along for a few months. But if it doesn't work, or is too costly to convert, I'll just scrap it and build my own control. I have some nice servo motors, Nema 42 I think(it has 5.875" bolt circle) with .625" shafts. They're 2kw motors and I have the matching 3ph AC drives, so I know it would be strong enough. Those drives can resolve down to 4000 increments/rev. If the ballscrew is 5tpi I could get better than .001" resolution, depending on how good the ballscrew is.

Do you think they're double-nut ballscrews? I won't be able to go get the machine for 2 weeks, so I can't take a peek at the screw yet.

Thanks again for your help!

[DLMACHINE]

Retro it! You won't be happy with it otherwise.The retro would be single phase and extremely low maintenance.

[damae]

Originally Posted by DLMACHINE Retro it! You won't be happy with it otherwise.The retro would be single phase and extremely low maintenance.

You're probably right. I can just rip out and replace the control, but what about the spindle motor? VFD? Or replacement single-phase deal?

Is there an aftermarket for the control? In other words, could I sell it on ebay to recoup any of my retrofitting cost?

Also, I'm still very curious whether or not rotary phase converters make a lot of noise while running. Anyone here running one?

[jderou]

mine (rpc) is quite annoying, constant hum. Unless you can mount it somewhere far away, or somehow insulated, you won't like it. But sometimes you gotta do what you gotta do.

[machintek]

Rotary phase converters are just motors. They will make as much noise as the fan on the end and how good the bearings are. The CNC will make a LOT more noise when it is cutting. even moving in rapid may make more noise than the phase converter. Good thing you have not listened to a BOSS 8 or 9!

George

[TR MFG]

As others have stated moving this machine will be hard to do up hill. I moved a M head bridgeport out of a garage once with an engine lift and thought it was going to kill the two of us! Rent a forklift or get a tow truck if you can.
As for the control if works and dose what you need it to ok. But if not look into an Ajaxcnc I think they make a kit for replacing Boss controls.

[DLMACHINE]

There are a number of retro comapines out there shop around.As for selling the OEM control, you can try but I doubt you'll find any takers.

I run a 20hp rotary converter and once you start working you don't even hear it.If you're only running the spindle motor then you can buy a static converter for less money.VFD tend to be alot more money.