Usefulness of a P&W 3B Jig Borer

I have a line on a Pratt Whitney 3B jig borer that needs to be moved ASAP. I guess the topic is more a generalized question of if this type of machine could be useful in an all manual hydraulic shop. Primarily building custom cylinders etc. also we take on one off job shop type stuff. Ton of shaft/keyway repair and line boring. Those who do have a jig borer and use it (however infrequently) what do you use it for that it does better than any other machine?. Trying to justify the sqft and honestly don’t know much about them. Good for bolt patterns and valve blocks I suppose? It’s in good shape quiet running. Looks to weigh about 15grand and not too top heavy. Moving it isn’t an issue.i do remember my brother and I admiring the one John O has. The one that needs moving isn’t quite as a looker, but still respectable.

No substantial milling - but superb on round straight holes on dead nuts location (assuming you have a way to know where you are - they came with "end measures")

No feeds except quill, though the table and saddle do have rapids (notice no mention of X and Y, since it would not know what I was talking about)

You nailed the weight

Large travels - at least 24 X 48, and 9 inch on quill

Terribly odd spindle nose and tooling for same

Pubs here as needed

We had a Reed Prentice No. 5 jig borer that has the same capacity as the P & W no. 3 had, but did not have near the accuracy. But it was a light duty miller when compared to a K & T no.5 vertical mill. Cut a lot of iron on that machine back in the day. I highly doubt you can find one today in good condition. Most of them died in the oilfield shops back in the 70's and 80's making reamer bodies and such. Ken

I ran a 3B in times past. Only used it for work that was too large for the 2A or the little Moore #1. All had DRO's. That was key to efficient operation, else what John O said. Get the tooling and the rotary table, and have fun.

Big old machines are near free these days. The rigging, wiring, and infrastructure are one time costs. The shop space they occupy is an every day cost.

IMO a DeVlieg is just as accurate and a lot more usable for general shop usage. Similar floor space requirements for the smaller machines. Compare spindle horsepower as to the amount of metal removal they were designed to accomplish.

Compare spindle horsepower as to the amount of metal removal they were designed to accomplish

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Indeedy - that "giant looking" motor on the 3B is really a 1 1/2 HP wimp with four speeds - meaning the gear box up there for spindle speeds is only a three speed box - and that massive electrical enclosure holds four each mag starters

The guy I bought the 3B from assured me it was at least 20 HP - and I smiled at him, knowing better

Yeah I noticed that went and looked it over again today was rebuilt in 92 based on tag a fixed to it. Maybe isn’t a good machine for our operation. May pass on the info for some who needs it (wants it?)