Bridgeport "Kit"?

I see that there is a strange (to me) looking Bridgeport vertical mill on Ebay right now. It is billed as something like: "Atlas 10F lathe and Bridgeport". It's item # is 330142641225 The picture shows what looks to be a Bridgeport J head or maybe the older head from a round column Bridgeport (is that the "M" head?) mounted on a square tube column which is, in turn connected to some sort of base plate upon which an X-Y table sits. So this is apparently a bench-style mill, not a knee mill. Anyway, did Bridgeport ever make such a machine or is this something that someone built up from a used J head and misc. parts? Was there some sort set of plans sometime in the past for using up surplus J heads this way? The reason I ask is that there is a company close to me that sells a lot of reconditioned Bridgeports. I went looking there one day and noticed several pallets of J heads in a rack. When I asked about them, the guy said that they don't sell any reconditioned machines with J heads; they convert them to the vari-speed type and so the J Heads just keep piling up. Not that I want to work that hard, but it seems like the head would make a good start to someone who really wanted to put the effort into making their own vertical milling machine.

Pete Stanaitis

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Reply to
spaco
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An old buddy of mine put together a very servicable mill out of a stray BP J-head and a Chinese POS. I doubt he paid much, if anything, for either... (Mark was a good scrounger...)

Very few of us ever work on anything that requires the full length of the table. Most of the time, it's just a few inches, held in the vise. Because everyone mounts the vise in the middle of the table, the machine tends to get badly worn in that area. But, if you mount the vise near one end of the table or the other, you'll probably find the machine is nearly as tight as a new one...

A lot of guys get the idea of simply welding something up. The problem is that steel is, by nature, springy. This is why machine frames are made of cast iron... Just remember, all machines are ultimately made of Jello....

Jerry

Reply to
Jerry Foster

A J-head with VFD is a great set-up. None of the mechanical vari-speed stuff to wear out and you still have the stepped pulleys to change the speed range if needed (hardly ever).

Randy

Reply to
Randal O'Brian

It is most certainly not a J head, even the 1J (step pulley) head is pretty big. This one could be an M head, maybe, but still looks too small even for that. The were others, the B and C heads, for other special purposes, and even less flexible. An M head isn't too bad, has a nice range of speeds, but no back gear. It is not good for boring and flycutting due to the lack of low speeds. They were made with 3 tapers, #2 Morse, B&S #7 and the proprietary "C" taper. If it is C taper, you're sunk. For milling, B&S #7 is a bit better, but there are a lot of options for the Morse taper, too. Either way, 1/2" is the largest collet you can get.

I upgraded my ancient Bridgeport to a 1J head and am VERY pleased with the result. I do boring and flycutting now with excellent results. I also get an extra inch of quill travel, which is real nice. But, on such a small machine, a 1J head would likely tip it over. If you want this just for the milling head, get one of those 1J heads from your contact, it will be a lot better overall. The R8 taper gets you a wide range of economical tooling. I use a VFD, and don't mind changing the belts at all!

Jon

Reply to
Jon Elson

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