Bridgeport Series One Buy or Not Buy

[isiahstites]

Considering buying this machine and fixing it up for my own use to build bike parts for my race bikes. I would also build those same parts to sell to others to support my habit.

The machine was removed from my friends fabrication shop and was put outside under a covered parking structure. As you can see there is no plenty of rust. The cover of the Heidenhain controller was left off and I see rust in various locations. Also the screen for the controller at the rear seems to have a broken bulb or something. When the machine was removed it was a working machine.

Any input is welcome as I do not know **** about these machines.

Whats it worth as it sits/ whats the most you would pay? He is trying to help me get my parts going, he offered it to me to use at no cost "just take it", but I do not want to put any money into it to get it running unless I own the machine.

[austin.mn]

I paid $500 for mine, it is an older Boss 3 model. Which has stepper motors on it. It was very easy to get it converted to Mach 3. I used a VFD to do the phase conversion for the spindle motor and I bought some Compumotor drives off ebay to run the steppers.

I am not certain what it would take to run the servos that are on that machine. I haven't had any experience with them, so I can't help you there. But I would happily spend $500 on that machine, or another just like the one I have. I use it a lot and it is a way better machine in my opinion than an import. It already has ball screws on all axis' and has a central lubrication system.

[isiahstites]

Originally Posted by austin.mn I paid $500 for mine, it is an older Boss 3 model. Which has stepper motors on it. It was very easy to get it converted to Mach 3. I used a VFD to do the phase conversion for the spindle motor and I bought some Compumotor drives off ebay to run the steppers. I am not certain what it would take to run the servos that are on that machine. I haven't had any experience with them, so I can't help you there. But I would happily spend $500 on that machine, or another just like the one I have. I use it a lot and it is a way better machine in my opinion than an import. It already has ball screws on all axis' and has a central lubrication system.

Thank you for your reply.

[TarHeelTom]

I bought a similar Series 1 this spring. I suspect that $500 (or a little less) is probably a fair price for that machine. Here's a link to my machine: http://tomwade.me/tw/machinist/nm/

There's a lot I don't recognize on that machine (but I'm NOT a Bp expert). I wonder if those are servo motors...

Bridgeport identified their operating systems with "BOSS" numbers. Mine was a BOSS 5.5

From what I read, at the current time, BOSS 8 (and later) machines seem to be quite stable. The guy I bought mine from spent a fair amount of money keeping the electronics running. For various reasons, I decided to pull all the electronics out of my machine and replace them with a PC and Gecko based system. For a stepper machine, this will run you perhaps $1000 if you can do it all yourself.

Do understand that there are two separate major systems here. One is the main castings portion of the machine, and the electronics portion of the machine. The main castings have a limited life, perhaps 500 to 1000 years. The electronics, OTOH, were nearly obsolete, and somewhat inadequate, when they were first built. I've never tried to keep those old electronics running, but the figure I've heard is $2000 per year.

But unless this machine is just plain worn out, it's probably a good candidate for a ground up rebuild. Strip it down to nothing, repaint it, throw most of those cabinets away, install a PC in it, and put it in service.
Roland Fiesbad wrote two nice series of articles on rebuilding these machines for one of the Village Press magazines. There are probably several rebuild threads here on this forum as well.

The catch here is that for a major shop, the Bridgeports served them well for the first 90 years or so. But now they are obsolete, replaced by the "machining centers". So there are a lot of Bp's and clones available out there for very little money.

Looking at the pictures, that machine has an air operated spindle brake, and an air operated motor to change the spindle speed. The spindle speed change mechanism seems to be a high wear item creating lots of noise. There is a thread here (I think) on removing the variable speed drive. You don't say if you have 3 phase power available, but these machines ran only on three phase power. Quite simple to run them off single phase using a Variable Frequency Drive or VFD. This is a solid state box which takes single phase or three phase power, changes it to DC, then generates a three phase output with a variable frequency. Much easier, quieter, and more repeatable then trying to set the speed with that air motor.

The big sheet metal pan looks like a flood coolant tank and catch basin. Usually these have all rusted out. On the machine I bought, he'd thrown away the metal tank and dropped the pump into a five gallon plastic bucket. On the other hand, a lot of people seem to be getting away from flood cooling and going to mist cooling. Lot depends on what materials you plan to cut.

Happy chip making.

Tom

[austin.mn]

Great write up on your site Tom. My machine is a floppy head as apposed to the ridged turret you have. Made it easier to get into my garage, but other than that fact I wish I had a rigid head. It seems that I have to check the tram every time I want to get a ridge free finish. I have even tried to really tighten the crap out of it, but still after a few days of cutting I still have to make a minor change.

Isi, I think that those are SEM servos, probably 140vdc units, and I don't know the specs on the encoder. I did see that MachMotion has a reasonable package deal on servos and drives that are a bolt on solution.

http://www.machmotion.com/Drives-and..._53/index.html

There maybe some one on here that can help interface the motors and drives you already have there. I know that I had read about using a MESA pci board to hook all that to the computer and run it from EMC2 I am not sure if that board will work with Mach though. I haven't looked into it that far.

Keep us up to date on your progress.

[isiahstites]

Thanks for the post Tom and Austin!

So if I understand you guys correct I can **** can the current control and go to a regular PC?

What all needs to be replaced to make this work and what does it cost?

Also I have single phase electric, what do the VFD run cash wise?

Thank you guys!

Scott

[austin.mn]

Yep, and that is what I would do instantly. An older control like that is going to be a pain. For one you would have to find an old computer to connect to it and then get a program from the manufacturer just to be able to drip feed gcode into it. Not that that is a super big deal, its just that by switching to a pc for control, you will have a lot of cool features you wouldn't have had on the original control. For instance, if you want to face a block of material, just use the wizard in Mach and it creates the Gcode for you right on the machine and hit the start button. Simple.

A VFD is going to be about $200 and is pretty simple to wire. Hooking that motor drive combo to a computer is probably going to be a little tougher and you are going to want to find any and all wiring diagrams you can pertaining to the electronics you have there. I am fairly certain that those are analog drives, which means that you will need to provide them with +/- 10V to get the motors moving. I believe you will need a Mesa 5i20 pci card to handle that chore. I did some looking into it a while back, as I wanted a closed loop system on my machine.... then I cheaped out. (actually, the machine as it sits does what I need it to do just fine, so I decided to keep some extra money in my pocket)

If you are comfortable reading basic wire diagrams and aren't scared to wire this thing up yourself you could have it up and running for under a $1000. Then you will need to start buying collets, endmills and specialty cutters depending on projects. That is where you will really start seeing the cash roll out the window. Nice thing about cnc though, you can get by with only a few different endmills. Sure it won't be ideal and projects will take a bit of extra time, but you can do it.

[isiahstites]

Originally Posted by austin.mn Yep, and that is what I would do instantly. An older control like that is going to be a pain. For one you would have to find an old computer to connect to it and then get a program from the manufacturer just to be able to drip feed gcode into it. Not that that is a super big deal, its just that by switching to a pc for control, you will have a lot of cool features you wouldn't have had on the original control. For instance, if you want to face a block of material, just use the wizard in Mach and it creates the Gcode for you right on the machine and hit the start button. Simple. A VFD is going to be about $200 and is pretty simple to wire. Hooking that motor drive combo to a computer is probably going to be a little tougher and you are going to want to find any and all wiring diagrams you can pertaining to the electronics you have there. I am fairly certain that those are analog drives, which means that you will need to provide them with +/- 10V to get the motors moving. I believe you will need a Mesa 5i20 pci card to handle that chore. I did some looking into it a while back, as I wanted a closed loop system on my machine.... then I cheaped out. (actually, the machine as it sits does what I need it to do just fine, so I decided to keep some extra money in my pocket) If you are comfortable reading basic wire diagrams and aren't scared to wire this thing up yourself you could have it up and running for under a $1000. Then you will need to start buying collets, endmills and specialty cutters depending on projects. That is where you will really start seeing the cash roll out the window. Nice thing about cnc though, you can get by with only a few different endmills. Sure it won't be ideal and projects will take a bit of extra time, but you can do it.

Thanks again! Can you break down where the $1000 would go to?

Scott

[TarHeelTom]

Think I paid about $150 for a NOS VFD from http://www.dealerselectric.com/

You can frequently pick up an old PC for perhaps $25 to $100. Oddly enough, the older PC's will do a better job than the newer ones. Try for a Point of Sale computer (Cash register). They come in a really small box.

Power supply for the servos, perhaps $150 to $200

Drivers for the servos or steppers, perhaps $500.

Break out board (BOB), perhaps $200. I used a PMDX.

I spent about $50 for heat sink for the Gecko drivers. Turns out I took out a ton of heat sink from my cabinets. Didn't need to buy any heat sink at all.

Software, Mach3 is about $150, if I recall, but you need to have Windows installed. EMC2 runs on Linux, and the two together are free. You're probably gonna need some CAD/CAM software, from free to several thousand dollars.

Screws, bolts, wire, tywraps, cords, plugs, etc will probably eat up a couple hundred.

I already had several monitors sitting around, and keyboards, and wireless mouse. Turns out you can't really use a wireless mouse, so buy a wired optical mouse.

In addition to that thousand dollars for the computer retrofit, you're going to need (probably) a vice ($600), hold-down set (<$100), and tooling. That machine looks like it has an Erickson #30 quick Change chuck. There are lots of collet holders and end mill holders available for the Erickson. In addition, NMTB #30 tool holders will also work. Some of them will work straight out of the box, but on others, the diameter of the flange will be too large by about 0.10". A few minutes on the lathe will cut it down to size.

Most of my holders use a DA180 collet. I'm buying soon another tool holder which will use DA300 collets, which covers the smaller sizes better, which meets my needs better. YMMV. But be aware that there are several different types of holders which will cover different sizes of collets

I've had good luck buying new in box NIB surplus tool holders from
http://www.tools-n-gizmos.com.

Tom

[austin.mn]

Scott,

I just pulled that $1000 from my butt... I didn't even know I had an extra $1000 laying around.. let alone in my butt...

You will really need to do a bit of research and see what you are really working with before you can actually put a shopping list together and add it up.

1. Check out the Servo specs, don't go by what I wrote I was just guessing from the picture. You need to know Volts, Amps, do they have encoders or resolvers? and most importantly do they still work?

2. Motor drives? what are they? Can you find a wiring diagram?

3. Is the monitor the only problem with the machine? I have seen old machines like that with a newer monitor sitting on a stand next to the controller and wired in. So depending on what kind of parts you need to machine, maybe all you need is a phase converter and an old monitor you can get for free.

4. If number 3 is the case. Your buddy probably has the drip feed software and and old computer to hook up to this thing and you can have it up and running with a home made phase converter you can build with junkyard parts.

Ideally you will want to get the control upgraded to a new control, just for the ease of use. But if the bottom dollar is the big issue, you can probably get this machine usable for little or no money. You need to get over there and write down every number you find on it and where you found it. Then google away until you find all the answers you are looking for.

[TarHeelTom]

Austin is exactly right.

You need to find out what you have and what you need before you buy anything. Doing the research might be a little bit tough, but it's doable.

Tom

[isiahstites]

I thank you both for all of the time you took to post. Your posts have taught me quite a bit as I am in the learning stages of the machines.

This information has been/will be very important on what/if I am going to do anything with this machine.

I already already went to Mastercam training and have already purchased the software, now I need a machine and tooling.

Thanks again fellas,
Scott