Looking for advice on a small (ish) mill

Wow thanks guys. I didn't get emails that I had any responses. This was really nice to come back to. I have a friend who taught me the basics of machining, who I found out has an old Bridgeport. He converted it to a full cnc system, but it's been sitting on a trailer for 4 years. He said every 4 months, he'd go WD40 it, and replace the tarps around it. He Wants to open up his own shop, but can't do it in the next several years, so he's been saving it. But he offered to let it live in my shop, so it has a purpose. I'd get a rotary phase converter to give it 3ph. But the table is pretty rusty. He said he doesnt blame me if I don't want to mess with it at all. But dang... I'd only be paying for Transportation costs, de-rusting and the converter. He mentioned we should convert it back to manual, but doesn't have the hardware.

I need to be able to bore these atv cylinders! I've had 3 come into the shop in the last week that I've shipped off to get bored. And the shop called and let me know they had an accident, and ruined a cylinder. Ah! So they're paying to sleeve it, then re-bore it. What machines do you guys have that you're looking to sell?
 
Congrats! Sounds like a plan! Might want to go the VFD route rather than rotary converter as it gives you easy speed control.

Pics or it didn’t happen!
 
How long are the heads you are going to fly cut???

Most of the heads we would do are single cylinder, but I do quite a few RZRs as well. Those heads are maybe 10" across.

And ACHiPo, we had talked about going VFD, but he said you can only get something like 70-80 % of the capacity of the motor with those, as opposed to the rotary, you can get more. Thoughts? And here are pictures. What do you guys think? Worth it? How hard would it be to convert it back to manual?

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That looks like a project. :) Never seen a BP like that before. Has a different table and knee than I have ever seen. Looks like an Ericson BT30 QC spindle.
 
Thoughts? And here are pictures. What do you guys think? Worth it? How hard would it be to convert it back to manual?
Well Crutches, I'd say you've got a bit more than a small mill there! That thing is a beast! If it runs and the axes move, it seems like it would be worth some TLC especially if you get to hang onto it for a while. Nice score.

It's definitely massive enough to do heads (and V-8 blocks!).

Regarding the VFD that motor may be big enough to be problematic for a VFD, although if it isn't, I wouldn't be terribly concerned about losing 20% power.
 
Looks like a Bridgeport Series II maybe

One of the few that are really worth what everybody goes nuts over

That is a much heavier machine than your typical vertical universal machine and will serve you well for your intended purpose. The "standard" Bridgeport mill is much too light IMO and tends to chatter, but not their bigger machines. There was a series of early NC mills that were about as rigid as one could imagine but being early NC, many were scrapped when the CNC became standard-I used to know where there were two, and I was offered one if I helped the owner convert the other to more modern electronics

You've done well young Jedi, and I hope,for your sake it lives in your shop a good long time
 
I don't think that mill was ever manual, and if it was converted, then someone went through a heck of a lot of work machining castings to install the round rails. That knee and saddle are nothing like anything I have ever seen on a BP, but looks like a factory instalation. It could be operated manually simply by hanging some handwheels on the axes.

Regarding the VFD that motor may be big enough to be problematic for a VFD, although if it isn't, I wouldn't be terribly concerned about losing 20% power.

That looks like a standard 2HP BP spindle motor, but could be a 3HP. In either case would be no problem for a VFD. And no, you won't lose 20% power with a VFD, you will get full power with a better torque curve. If you were using a static phase converter, then you would lose about 33% because the motor is only running on single phase
 
I don't think that mill was ever manual, and if it was converted, then someone went through a heck of a lot of work machining castings to install the round rails. That knee and saddle are nothing like anything I have ever seen on a BP, but looks like a factory instalation. It could be operated manually simply by hanging some handwheels on the axes.
That is Bridgeport's first entre into the world of NC and I think you'll have a LOT more work trying to put handwheels on it than you'd expect and you'd be disappointed in the performance.

With new electronics it can be a Helluva machine
 
Alright guys, it's been a journey... I bought a rottler boring bar on ebay shortly after making this post last year. I've been boring atv cylinders with it, and it's worked, but I've needed a mill to do other things. So I bought a 50's round ram Bridgeport in ebay that had a J-head installed. Long story short: freight companies were a nightmare to deal with, and kept having logistic errors, which caused the seller to get mad, and repost it. So I lost it. Ill get my money back, but don't have the mill. I was telling this friend of mine about it, and he said. "well that Bridgeport is still sitting on the trailer. I'd like to not have to worry about it. It's yours. Take it for free. Clean it up and use it and it's yours."

So he said it's a Bridgeport series 1, that the company he worked for upgraded. It has full linear ball screws on the Y that are tight, can do 0.0005" well. He said we should ditch the cnc, convert it back to manual. They put a 54" table on it.

So I'm going to go up (about 2 hours away) and we will see about getting it onto my trailer. So here's my questions:

Advice... What are the first things you want to say about it? (or about how much you hate me )

Where do I start? Soak it in wd40? Take the table off?

Just sit and drool over it?

Where can I source hand cranks for it? Besides ebay?

Thanks! I'm excited for the journey.
 
Well, the price is right. If you have the space jump on it.

Don't know if I would bother converting it to manual, you'll get better cuts with the servo drives and providing they work it should cost a lot less than finding/fabing all the stuff to change it. The control and drivers have come way down in cost since that unit was built and LinuxCNC is free.

Disclaimer, I'm just getting started with CNC but I am a computer guy. I also used to own a small engine shop and did racing kart engines so I know what kind of work you're doing. I suspect a lot of folks think CNC is going to be too complicated, or the time to do a set-up will be a lot more than just putting their work in the vise and cranking away with it. Your buddy might be one of those, or he might really know why this particular machine would be better manual. However, I'm gonna bet it will take a lot less time, effort, and $$$ to update the electronics than to try and convert it to manual. Most people go the other way for a reason.

There are lots of folks on here and CNCZone that will be helpful and with a machine like that you can even ask questions on Practical Machinist. Off the top of my head you'll need a control board (I bought a 5 axis for $20), servo drivers, and an older PC besides cleaning it up of course. I would figure out what the servos are and get one driver to test them with first. Once you get it running you can use a pennant to control it without having to actually write a program for what you need to do.

BTW, there are much better ways to remove rust than WD40 but that table doesn't look too bad. Some scotch brite and mineral spirits might be all you need.

Congrats on your score, keep in touch and if you're looking for a small engine dyno let me know.

Cheers,

John
 
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