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1944 Bridgeport with J head

So one would have to really try to mess up a spindle bearing? I’m guessing a fully retracted quill is quite strong as well.

Not that I want to encourage anyone to do something they aren’t comfortable with to their spindle.
H&W uses that same stand to remove a Bridgeport head while on the road.
 
I've taken off the head and it is as I suggested. The J-head's lower 2 bolts have different locations than the round ram head's. I used some transfer paper to get an image of the differences since it was difficult to get a good measurement freehand. As you can see the bolt holes in the ram are fixed (not T-bolts) and the lower 2 bolts in the J-head are about 5/16" closer together and 1/8" lower than the "matching" holes in the ram. Not going to work. The person that assembled this unicorn lucked out that the top 2 bolts matched up and called it good. I'm going to make the assumption that the J-head is the correct pattern seeing that the holes have cast bosses but if someone knows something different let me know. I've got a few options here that exclude disposing of this 1944 wonder to the scrapyard. I could get matching parts, machine up an adapter plate, or leave it as is. First option is a possibility but I'm not sure how much money I want to stick into this machine seeing its age and capability. 2nd option is the most likely since it wouldn't be that difficult to make. 3rd option is not the way I like things to be. Nothing like seeing the actual issue to bring reality to a subject. Just to bring clarity to the pics, 1st is round ram, 2nd is j-head laying on its side, and third are the transfer hole pics.
 

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It must match up to something that was mounted on the round ram. Thought with all the experience on this forum that someone would have seen this setup before. I've heard of some adapter plates that were made in the past but can't find any definitive record of their use. I know there is some conversations about this but they were more about M-heads that had the head that could nod. That is not what I have. Thought it might have something to do with the nod joint but pictures of this show it mounted to the flattened flange on the other end of the round ram. Some round rams have this same flattened feature on both ends of the round ram.
 
Maybe the original bolts were broken and replaced with t nuts? So you just need to loosen the top 2 bolts and rotate the head back and forth to get the bottom 2 bolts started?
The t slot bolts fit behind the head and the threads face the operator so there is not turning the head to “get them started”.
Essentially, all 4 long t bolts are inserted into the circular ram face and you carefully slide the head onto the bolts. It is very tricky to do by oneself. They want to move around and not align. Get a helper and all is fine.
 
I am aware of how a Bridgeport head is normally attached- this is not the case here. He has a round ram with no round slot or t bolts. We were troubleshooting possible problems- I was suggesting that if he had t bolts perhaps the lower 2 had been replaced with t nuts.
 
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