How good is a bad Bridgeport?

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Just trying to get an idea what conditions to settle for in a used Bridgeport. I have a round column 8x28 now, it is what it is but within its envelope it does good work. If I'm looking at used and possibly abused mills, how much wear and tear on a full size B'port would still be better than a new square column from China?

I know that is a really subjective question without a definite answer, but I don't know how else to put it. I'm not talking about needing to replace a motor, or cross feed, just the basic wear and tear on the ways, table and spindle. I don't want to buy one and need to do a full rebuild and scrape the ways to get it where I can use it. I can handle backlash with careful use. I won't be making parts for NASA, this would be for a home shop, I need the machine to hold at least .005" and a minimum of .003" would be better.

Scott
 
I've sold nice BPs in the $3000 range , all with readouts and power feeds . They were variable speeds , the pulley heads were $2200-$2400 . I have a BP in the garage that I might be selling soon , at this point , I can't get the Kubota into the garage . :(
 
How much better is a worn BP compared to it's high grade clones, like Lagun or the Taiwanese badges like Acer, Sharp, Atrump, Supermax, etc?
 
I had the Lagun FTV-2 and loved it . 10 x 50 inch table . It went to some foreign country that the buyer was queen . No kidding . :grin: Showed up in a Rolls Royce and peeled out 31 Benjamins , picked it up the next day .
 
Once saw the table shift a 1/8” as it entered the work on a worn out Lagun. I determined this machine to be garbage, and never again graced the handwheels with my loving embrace. But my supervisor, a toolmaker of forty years, uses that machine day in and day out, turning out “one off” parts to tolerance as if it were a brand new machine. He even repainted it, and has had it moved twice, in order to keep it nearby his office, as he’s been shuffled through departments. How good is a bad Bridgeport? About as good as the man at the cranks.

Even so...I’d buy the new square column.
 
Speaking from experience,
I owned a worn out Bridgeport,
I was able to do some decent work. Having a knee mill is great.
It’s frustrating that the full travel of your X axis goes from smooth as glass (loose) to very tight at the ends. A bent table is common.
Over torquing the T-nuts over the years causes the table to warp. The slop in the ways is common, you can overcome it by locking down everything you can.
I don’t have the time or energy to rebuild a worn out mill.
Buy one that serves you well.
My 2 cents sir.
 
Personally I'm not a fan of the Chinese machines. I've used a few in my day, but they were disappointing experiences compared to the US made iron. I do own a Bridgeport, but again it was not originally my machine of choice. I was originally looking for a Tree brand machine, specifically the 2UVR model. We had several Bridgeports, and Trees in our shop, and the Trees were by far the easiest (for us short guys) to setup and use. Changing tooling was easier, and the Tree machines seemed more stout and less prone to vibration.

That being said I looked for over 2 years for my first mill and found every Tree machine on the market to be either wildly over priced, or worn to the point it would have taken more time and money to refurbish than it was worth. In addition I found the tooling to be far more expensive and much harder to find.

One thing I did note throughout my search was that machines that appeared to be run hard and put away wet generally reflected lack of attention in their state of repair. Those covered with dried cutting oil, filthy oil and grease fittings, and covered in chips showed far more wear than those kept clean and regularly lubricated. On the other hand those with no signs of having been used, and sporting a fresh paint raised red flags as to what the condition of the machine was before the new paint was applied.

I almost put purchasing a mill on the back burner until someone alerted me to one from a local high school that was sold at an auction. The buyer bought it as part of a lot and was only interested in keeping another machine in the lot which happened to be a Clausing lathe. I contacted the buyer and went over for an inspection. What I found was a mill in reasonable condition for a reasonable price. There was about .030 backlash in the X lead screw, and .020 in the Y lead screw. The table didn't bind throughout the length of travel, and did not get tight near the ends. The variable speed head was quiet and would easily shift from high to low range, and the auto down feed worked properly. About the only problem I found was that the ram wouldn't change position regardless of how loose the retaining bolts were. After an extended period in storage the ways on the ram had rusted to the point the head wouldn't move. About a weeks worth of daily doses of penetrating oil finally freed the head.

Digging into the history of the machine I found it was originally purchased by the high school in 1972. It was in their machine shop until about 1992. At that time it was replaced by an early CNC machine and sent into storage. In 2002 the school district deemed it to be surplus and was auctioned off at that time. Essentially it sat for 10 years in a store room. If the machine is being sold by the original owner they should be able to provide some history. If it's being sold by a vendor they should know where it came from and what type of work it did.

I guess my point is that a relatively thorough inspection will needed on any machine you are truly interested in to be sure the machine will be "reasonable" condition. Many can be dismissed due to obvious lack of maintenance and operator care. Patience and perseverance are the keys to finding a good machine at a reasonable price. Don't be fooled by a machine that looks shiny and appears to have little or no wear. These machines were purchased to work on a daily basis. If the normal wear parts like crank handles, feed levers, and adjustment fasteners don't show some wear proceed with caution.
 
There was a pretty nice looking B-port clone on Dallas Craigslist not long ago. I see some from time to time up in your area. There's a Craigslist ad in San Angelo for a guy selling out a machine shop. He lists two mill/drill machines (a large and a small), but doesn't have pics or any description. The large one could be a B-port, or may be something else.
 
My question is difficult to put into words, both the asking and the answering. Let me put it in terms I am more used to.
I've been a commercial mower for several years, putting it in those terms..... A commercial Scag zero turn rider is a pure joy to use. It cuts great, has lots of power to get through tall and thick grass and even light brush. A Commercial Scag with thousands of hours on it isn't anything a pro would keep using in most cases. But that same unit for a guy with a large yard he mows once a week would still be far and away better than the 38" rider he could get new at a big box store.

Does a B'port knee mill start out with such a high level of quality and accuracy that even after years of use and wear it is still better than an new square column?
 
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