Bridgeport mill advice, about to pull the trigger

I have been off and on looking for a mill for a while now. I'm gonna look at this mill today and I am prepared to bring it home with me if all goes well. It's a Mill, bridgeport, Series I, 2HP, serial #2J-74250 table size 9" x 48". It has no tooling with it. Suppose to be in really good shape and comes with motors for a cnc conversion(I will be using it manually only). Its right under $1000. What do you guys think? I am still looking for a lathe too. Thank you in advance.

 

Sounds like an OK deal. Check it out and make sure the head functions OK, especially if a variable speed. Keep in mind tooling can set you back a lot more that what you will be paying for the machine, vise, indexer, collets, etc.

 

Not faamiliar with that particular Bridgeport at least I don't know the numbers on it. But the question is do you have 3 phase power?
If not then the price of the unit is usless if it is a 3 phase unit.

Check and make sure that the quill is tight and the table doesn't have any slop.

 

Are the servos already hooked up for X and Y travel??? Does it have one Z travel also??? For a grand, that's pretty cheap for a used Bridgeport...

 

That's not a bad price if it's in good shape. Check the ways of the machine- if it's easy to crank in the center of the X and Y axis, but stiff out at the ends, that indicates wear in the ways, and will mjake it difficult to do dead nuts accurate work.

And if the motor is 3 phase, you're not dead in the water- you can get a phase converter and run it on single phase, but that's going to add to the cost.

 

Just buying a single phase 2HP motor is probably cheaper than getting a phase converter, although you can buy used rotary phase converters for 5HP and below for a couple of hundred bucks.

 

what's the quill taper, I had one that was #2 morse and it was almost impossible to find tooling for it. You want anything else.

 

That's a '64....should be 3-phase.....any part is still available.....easy to work on......spindle bearings are $$$$$$.....an import clamp kit,R8 collets,endmill set will run 200.00....it will be a good start.....you need a good vise, Kurt are the best....if it's not beat, 1k isn't too bad....check the ways for wear.....mine is a '58 I bought from Scootermcrad....

 

+1 on what everyone else said. $1000 isn't a bad deal at all if the machine is in pretty good shape and needs only minimal work. We all have different goals though. The kind of machining I'd be doing now if I had mill would be much cruder tolerance wise than when I was building SAE cars at the University of Delaware, where thousands of an inch mattered.

One thing I will say is that your life will change immediately with the Mill in your shop. Having one is like having an AK-47 in your arsenal when everyone else has pistols. Don't be afraid to pull the trigger, you'll be thankful you spent the money

 

Yeah, but those mounting flanges are Bridgeport specific, aren't they? I had no idea that phase converters were so expensive- me and my buddy made one for his mill.

And yes, the tooling will set you back a ton- if you buy it all at once. Start with the vise, a set of collets and a chuck. You can do quite a bit with just that. Add the other stuff as need arises or as good deals come your way.

 

You can get a new one for that price.

 

Sounds like a deal... does it come with a digital read out? Bridgeports will always be worth something. I have an old one, I run a phase converter "static"... for the work i do its perfect. Most of the time its aluminum anyway but either way I'd buy it. Look in your area for an industrial surplus company...the guys that buy out old shops. You can usually make pretty good deals when you deal in cash... there is always Harbor freight to get ya going.

 

Thanks for all the replies. I will be getting a phase convertor. It a 2hp 3ph motor. It's suppose to the the cnc motors on x, y, and z. Can I sell those for anything? For the tooling I plan on buying it as I need it. Start with small stuff and work my way up. I'm hoping to not need things like a rotary table since I want a lathe too.

 

Dont mean to hijack thread but bought a used Jhead couple years ago. How do you tell the year? Mine has 11x52 table and very large base not seen one like it is this unusal? Good or bad? Thanks

 

my serial is J 99937 what year does that make it? Thanks in advance

 

You can buy an electronic phase converter for under $200 to handle that motor, but it will not instant reverse unless you add a "slave" motor to make it a rotary converter. That is less $$$ than buying a commercial rotary converter. I did this for my B'port.,,,plus, you have 3 phase for other stuff up to the full HP capacity of the elctronic unit.

 

1967...

 

I hear the a rotary convertor is the way to go. I don't want to skimp out on the electrical part.

 

does it have a power draw bar? those are nice, never used the manual ones but I would never want to either. If you are into restoring, the ways can be scraped and restored, a time consuming job to be sure. generally only the x feed (the long axis) will really be the one that wears, since its the main feed.

also, cnc conversion generally needs ball drive lead screws, the acme screws have way too much end play, are you sure it isn't just power feed motors? definitely keep those.
you can set up the stops for the power feed, and do repetitive operations pretty easy.

again, the x axis is the most useful for power feed, but the z axis (up n down) is great because that one battles gravity, and you use it for switching out tooling all the time.

3 phase conversion is easy, don't let it put you off.

and tooling is expensive, but you can find lots of used tooling. lots as in package deals.

also a machine shop with a mill and no lathe is like a one legged man. its only half the equation! I would almost venture to say I would rather have the lathe than the mill.

 

If you are a scrounger you can build your own phase converter for near dirt. 3 phase wouldn't slow my decision process for a single second. Besides I've never seen a 2J that was single phase though anything is possible.

The price is MORE than fair if it's in decent shape.

If it has servo motors it likely has ball screws as well - they usually hold up MUCH better than acme screws, but can backwind under certain conditions - nothing to be leery of just good to know IMHO.

Loosen up the table locks and grab the end of the table and give it a good yank (perpendicular to the travel axis) and see how much play it has. This is also a good indicator of wear in the ways. Of course wind it back and forth and check the flaking - - chrome ways are a plus but probably more costly if you end up wanting to have it redone. Best bet is to buy something in great shape and not have to live with a turd for however long you can stand it. Buy the one with the nicest ways you can find!!!!

Personally I love the 2J versus the step pulley machine, but with VFD's they are almost a wash - I still prefer the 2J. Personal preference.


I run a 2J at home on a homemade rotary converter - works great!!!



BTW - run the spindle down and check out the surface - if it's damaged by the spindle lock it's a pricey repair. Some slight marks there are normal, anything more proceed with caution.

 

Definitely get a rotary converter and you can build one for peanuts. Everything thats pertinate to you has been posted and I'll confirm if the table has reasonable wear (just slightly more difficult to crank at the end of table travel) you won't get hurt at $1000.
As you stated you wanted a lathe also so you had better be prepared to spend a lot more time in the shop. With those two machines there isn't much of anything pertaining to car crafting that you can't make.

Frank

 

When I was an apprentice machinist, many years ago, an old toolmaker taught me a lot about using a bridgeport as a Lathe. As long as its not too long you can turn lots of parts. And, I use several 3 Phase machines with a convertor on single phase.

 

Eviltwin: Peruse this article on how to evaluate a milling machine before buying.

http://www.mermac.com/freemill2.html

 

It is easy and cheap to build your own static phase convertor if you have a little electrical ability. I have used one on my knockoff mill for several years. It has given no problems, although it doesn't start under load. You have take the load off for startup. This isn't a problem with a mill as you back the tooling off before shutdown and restart anyway. I have attached a scan of an article that details how to do this. Once the convertor is turned on then you can start the mill. And yes you do have to stop between forward and reverse.

 

Dito

 

If it doesn't have a digital readout, put that on your short list of upgrades. When doing repetitive stuff, it really speeds things up.

 

Sounds like a good deal. I have the same machine but with a 1.5 HP drive and couldn't get by with out it.

3 phase is easy to obtain in a single phase environment. I run a 16" South bend lathe and my bridgeport at the same time off of a 10 HP rotary converter I built myself. Not too hard to do.

 

I have the same size and vintage J head machine. Mine is 220V 1ph and i love it. It is a good buy if the x and Y axis are tight and the quill is tight. also make sure the auto feed quill works if it has one ( i didnt look up the number).

 

Check for wear. Thats the biggie. As many mentioned the 3 phase isn't that much of an issue. You will learn to spot tooling from yards away at auctions. I use my manual unit more often than the cnc.

 

What voltage is the motor? If it is 440V a phase converter won't do you much good if you only have 220V house current to start with. You may need a transformer. I bought a VFD for my lathe for less than $100. Was for a 1 hp motor however. The price of the Bridgeport is reasonable even if you have to get a new motor.