I have two of them. They were popular at The Washington Navy Yard and when the Gun Factory closed they showed up all over town. One was given to me by an old Navy Yard guy, it's the one with the No.5 MT shank. The other one has a No.9 B&S tang drive shank.
The tools are marked "Precision Universal Tool Head"
"The Precision Tool Co, Brooklyn, New York"
Check your serial numbers, mine are:
The owners of the company retired to Clearwater Florida some time in the 70's and took the rump of the company with them. They reconditioned 2- 4915 for me and sold me a new wooden box for it.
The shank and the head are all one piece. The boring slide is driven by a pinion to a rack on the under side of the slide.
There is a big threaded collar that has a rack on it's inside. That rack meshes with an idler that meshes with the slide drive pinion. as the threaded collar moves axially on the shank, the slide moves across the head.
The mechanism that you see on the outside of the tool controlls the nut that moves the theaded collar. It is all on ball bearings so the tool can turn but the slide will only move when the little hand knob is rotated.
This is the setting knob and it also controlls the out feed facing feature.
If you are experienced with fine mechanisms and are patient, you can take the thing apart and see how it works. There are a zillion 7/32" balls in there (ask me how I know the size) so be careful.
No, you can't change the shanks without going through Much pain and terror.
I use the B&S no 9 shank with a 9 B&S to 40 MMT taper adapter.
I am saving the No 5 Morse shank for The Boring Mill of my Dreams.
I have no idea of how many of these were made. The company was always small. The first two digits of the serial number might indicate the year of mfg. I know that neither of mine are younger than 1950.
As to being marked "Bridgeport, Conn." I have never seen one so marked and the owners of the company never mentioned that they were in B'port.
Yes, Bridgeport has always made machinery, but it would surprise many people to know how many fine mechanism shops were located in Brooklyn. The place was like Switzerland with a funny accent and a wonderful baseball team.
If you have a serial number lower than 2- 34, the company might have started there. If it is higher than 2- 49 the company might have moved there before going to Florida.
You don't have a "from" tag. You might not know that Bridgeport, Conn is for all intents and purposes, a suburb of NYC, although not as fancy as Darien and Stamford.
oooooh, did I say that!
If you have the 90 degree bent boring bar, do you have the adapter for it?.
The adapter not only is held to the slide by the normal retaining screw, but it also has it's own allen head screw that fits into the slide to help hold it.
If you don't have the adapter, don't try to ue the 90 degree bar. Don't.
If you do have the adaptor but don't have the installation instructions, I will e mail them to you.
If you don't pay attention when installing the adapter and the 90 degree bar, you will have an horrendous wreck.
I have used these heads and also have used the Wohlhaupter heads. I have a preference for the Precision Tool Head.
I think I am going to catch hell for that remark!
Hope to have been of some help.