The Bridgeport Sold for $995. A Court Ruled Anyone Could Copy It †
Precision Valley
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For sixty-four years the Bridgeport knee mill was the machine every American shop trained on - head on a ram, ram on a turret, table on a knee, a drawbar wrench hanging beside it. Production in Bridgeport, Connecticut ended in June 2002. What finished it was not a better machine.
This video follows the whole argument, from Rudolph Bannow's 1936 sketch on a paper bag and machine number one in 1938 to the copies that began arriving from Taiwan in 1975 - Kingport, Millport, Newport - and to Textron's 1982 complaint at the International Trade Commission naming forty-three firms. The survey it commissioned found sixty-one percent of machine shop employees calling a Taiwanese mill a Bridgeport, and that recognition is exactly what sank the case.
The Commission ruled the silhouette functional and generic; the Federal Circuit affirmed in January 1985. Bridgeport had taught America to machine so completely that the shape stopped being its own. If you trammed one of these heads, chasing the last thousandth around the dial, tell us which shop and which year.
#bridgeport #milling #machinetools #manufacturinghistory #machinistlife
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The Bridgeport Sold for $995. A Court Ruled Anyone Could Copy It †
Precision Valley
9,882 views
For sixty-four years the Bridgeport knee mill was the machine every American shop trained on - head on a ram, ram on a turret, table on a knee, a drawbar wrench hanging beside it. Production in Bridgeport, Connecticut ended in June 2002. What finished it was not a better machine.
This video follows the whole argument, from Rudolph Bannow's 1936 sketch on a paper bag and machine number one in 1938 to the copies that began arriving from Taiwan in 1975 - Kingport, Millport, Newport - and to Textron's 1982 complaint at the International Trade Commission naming forty-three firms. The survey it commissioned found sixty-one percent of machine shop employees calling a Taiwanese mill a Bridgeport, and that recognition is exactly what sank the case.
The Commission ruled the silhouette functional and generic; the Federal Circuit affirmed in January 1985. Bridgeport had taught America to machine so completely that the shape stopped being its own. If you trammed one of these heads, chasing the last thousandth around the dial, tell us which shop and which year.
#bridgeport #milling #machinetools #manufacturinghistory #machinistlife
Bridgeport went into receivership, and Harding bought them, lock, stock, and barrel. Harding still makes the Bridgeport. Modern Hardinge Bridgeport milling machines are designed, engineered, and assembled by Hardinge, Inc. at their plant in Elmira, New York, though the heavy castings and primary machining are predominantly produced overseas in Taiwan or China. They are still good machines - they are tight and they perform very well. You can hold tenths on a new machine. Whether the ways are hand-scraped, I could not tell you, but I wouldn't bet on it. Mine are. Mine was built in the 1970s, and I bought it used from a friend. Also, that was an incredibly stupid court ruling, that you can't copyright or patent (did they bother to do either? I don't know.) the design of a product - that's ludicrous.
Shoppers: if you buy a used Bridgeport, listen to the voice of experience): buy a rotary phase converter, do not even THINK of replacing the US Motor unit that came from Bridgeport. Those things are so ridiculously underrated that you can run production all day long, hogging big chips, and at the end of the day, that motor will still be as cool as a cucumber. You want that motor. You do not want to replace it. So you will need to feed it three phase power. It's not that big a deal.
Do not buy a so-called static converter; they do not provide true 3-ph power, the phases are all at the wrong angles to each other, this results in the available motor power and_torque being cut by anywhere from one-third to one-half! Static converters are strictly a half-assed solution.
Do not buy a VFD. They seem to be the perfect solution, and they are utterly silent. Until a power outage nukes its memory and you have to reprogram it... again, or a power line surge destroys it utterly, or it has some other complex internal fault that you can't fix without a master's degree and an oscilloscope. If you insist on having a VFD, install the recomended outboard braking resistor, but double the power rating and heat sink it properly. Cuz you know you're gonna want to play with the braking feature, since it lets you be in a hurry, which is always a great idea in a machine shop... your mill does not need acceleration and braking features. You can live a fulfilled life without those.
Just buy a rotary and forget about it. It's not that loud and you will have it for life. Do not buy a converter from Tower Electric or TECO, if they still exist. Terrible customer service, shipped bad product.
I have heard good things about American Rotary Converter (both customer service and product quality) in forums and in YouTube channels, but I have no direct experience with their brand.
Make sure the mill has a one-shot oiler already installed, that works properly and feeds oil to all points. There are a lot of points so it is tedious and time consuming to make this check but if you don't do it, you will regret it. If it hasn't got one, understand that installing one involves taking apart major parts of the mill, and drilling holes in them. It is not a trivial chore.
Always ask whether it includes any tooling, such as a vise. If it includes a free vise in poor shape, sell it and buy a Taiwanese clone of the Kurt. Mine opens three inches larger than the Kurt and cost half as much, and measured and printed just as accurate, flat, and straight on my surface plate as a friend's Kurt. Caveat Emptor, you're paying for the name... Forgoe the included vise handle, I hate it. There is a German fellow selling a three-handled vise handle called 'Super Spinne' (or something like that) on eBay and probably elsewhere. I ADORE that thing, seriously. It can stay on or come off like the standard handle, but I just leave it one. One less thing to hang off the front of the table...
Does it include anything else? (cutters, collets, a drawbar wrench, how about a toe clamp kit? You'll need one of those.)