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Help. Just purchased a Pratt and Whitney bench lathe

Browning1932

Plastic
Joined
Jan 25, 2020
I just purchased a Pratt and Whitney M-1689 bench lathe. I’m new to machining and need help with a few items. To begin with it’s not under power I haven’t gotten a phase converter yet. My first question is theres a collet in lathe how do I get it out. Second what do I need to convert it of a 3 jaw chuck. Third it came with a tool holder but no tooling what does this other use for tooling and finally I need a steady rest for the tailstock what size and style do I need. Here are a few pics
 
First thing to do is get a copy of How to Run a Lathe by the South Bend Company. Second, Google Images is your friend.
Have fun on your new journey in metal and machining. It is an endless and satisfying passion for many of us.
Best regards,
Chuck
 
Thanks Chuck. I’ll check out both of those options. Can any one tell me also how to post pics from my phone on this forum
 
How To Run A Lathe

All sorts of vintages available including this jam packed one from long ago

http://vintagemachinery.org/pubs/1617/5795.pdf

P& W will likely have a "draw tube" passing thru spindle holding the collet in - these often have hand wheels on the left end that allows you to turn the draw tube to tighten or loosen the threads holding the collet in

Finding stuff for such an antique will be lots more trouble than just making what is needed

As to photos, here is a place to ask that question about doing it with the phone

Posting Pictures on the South Bend Forum
 
If an earlier No. 3 lathe, chucks are held on the spindle by the collet draw bar and a proprietary outside taper. If a 3C lathe, the chuck mount is a cam lock D1-2", which was only used on a couple very small lathes and is now obsolete. If a 4C lathe, I believe the spindle is D1-3".

Andy
 
Thanks guys for the help. I found the draw bar. Was unsure if I got it with the lathe. I will attempt to remove collet tomorrow
 
Thanks guys for the help. I found the draw bar. Was unsure if I got it with the lathe. I will attempt to remove collet tomorrow

Removed collet. A little bit of rust locking it in place. Could anybody tell me what style collet this Pratt and Whitney 10x20 bench lathe uses
Thanks
 
Removed collet. A little bit of rust locking it in place. Could anybody tell me what style collet this Pratt and Whitney 10x20 bench lathe uses
Thanks

You can "tell yourself", actually. Plenty of information if you but search.

They aren't really forgotten and mysterious. Minor legends, and historical, rather.

Pratt & Whitney Lathes

Pratt & Whitney Co. - Publication Reprints | VintageMachinery.org

Pratt & Whitney Co. - Photo Index | VintageMachinery.org

Photo Index - Pratt & Whitney Co. - M-1689 | VintageMachinery.org

Several PM members - and "not only" - have, and have repaired - P&W lathes, tiny bench clear up to geared-head "majors".

P&W's machine-tools unit became part of Niles-Bement-Pond nearly 120 years ago if you were not aware, but also kept their name and was positioned as the "jewel in the crown", then outlived that main body of N-B-P as well.
 
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Thanks for all the info. I've learned quite a bit tonight thanks to you guys. Appreciate it

Figure the "built-in" collet-closer taper only needs one or several of:

- A bushing that extends forward very little, but adapts to some more common collet. 3C? 5C? Pre-threaded tubes are available. You can make a "handwheel" drawtube closer very easily.

- A few "stubs" to fit the taper much as if it were Morse or jarno. These can be held-in with a simple draw bar (rod), not tube. ONTO such "tails" you can mount lots of things. Small flat-back chucks, drill chucks, etc.

==

The D1-2 snout is rare, but folks "right here, on PM" have DIY'ed D1-3, D1-4, D1-6, so that, too, can be done, and then you have back(s) for mounting more flat-back chucks. Or nose-mount, nose-operated collet closers. ER 40, 5C, 2-J, Rubberflex, Burnerd multi-size on my D1-3.

IF you have a working 4-J on it? You can grip and center:

- a "plate mount" ER-(nn). I use an ER 40 for repeatable INTENTIONAL offsets from center. Or you CAN centre it dead-nuts.

- A flat-back key-operated 5C. Same again. Repeatable eccentric turning. Or dead-nuts.

No idea how much OEM goods are still out there, used, for the D1-2, but.. this WAS a widely sold and widely used lathe "back in the day". "Scarce" now is not the same as "zero".

And you only have the ONE to support. Not a whole factory full of them!

As with a vintage motorcar, there are challenges. But if beats all HELL out of having a common F-150 .... or "South Bent" lathe, don't it?

:)
 
Figure the "built-in" collet-closer taper only needs one or several of:

- A bushing that extends forward very little, but adapts to some more common collet. 3C? 5C? Pre-threaded tubes are available. You can make a "handwheel" drawtube closer very easily.

- A few "stubs" to fit the taper much as if it were Morse or jarno. These can be held-in with a simple draw bar (rod), not tube. ONTO such "tails" you can mount lots of things. Small flat-back chucks, drill chucks, etc.

His machine is pretty modern - it may use a standard morse taper in the tailstock. Mine did not, I simply made a new tailstock ram to fix that, and also
undo the wear on the underside of the non-split tailstock.

His spindle likewise probably does not use the smaller collet. The older lathes will take a suitably modified 3C directly in the spindle. The keyway in the collet
needs to be lengthened by about 1/8 inch. A carbide end mill is needed for this, the collets are pretty hard. Draw bar as you say can be hand made, but
a thrust bearing is a must. Again easy to make from stock parts.

If I had to move to smaller quarters, that would be the one lathe I would keep.

pw_lathe_vfd_3.jpg


PW_lathe3.JPG


The drawbar is as mentioned home-made. It did not work well at all without the thrust bearing:

Drawbar1.jpg


Drawbar3.jpg
 
I'm with Jim. Those old clock/instrument makers lathes are some of the nicest machines ever. I love my Stark #4. It's an absolute joy to use and is most definately good enough for clockmaking.

I had one good male tailstock center that came with the lathe, so i chucked it up and set the cross slide angle to match using feeler gages and trial and error and then turned a few blank tail stock tapers. They work just fine. Good enough for clockmaking! My lathe also came with a catch plate for the headstock that has the same taper as the tail, so machining the working end of my tapers was a snap.
 
I been doing a tone of research past few days. I’m going to make a backing plate to accept a D1-3”. I looked up ASA/ASME B5.9 spindle noses. They have no listing for the D1-2”. It starts with D1-3”. I did find the schematics for a D1-2” online at lathes.uk.com but it was unreadable. Does anyone on this site have a digital copy. I will have to make this off site and won’t have access to my lathe for reference.
 
I been doing a tone of research past few days. I’m going to make a backing plate to accept a D1-3”. I looked up ASA/ASME B5.9 spindle noses. They have no listing for the D1-2”. It starts with D1-3”. I did find the schematics for a D1-2” online at lathes.uk.com but it was unreadable. Does anyone on this site have a digital copy. I will have to make this off site and won’t have access to my lathe for reference.

I think you mean D1-2?

Here's a listing:

AMERICAN LATHE SPINDLES SPECIFICATIONS

Natchurly, you have a "3-D model" right in front of you.. or you would not have the need! EG: It has to FIT your lathe. No other, actually.

Seriously. "Job One" is to make a fitting-dummy duplicate as a test gage for the "many" backplates.

Taper & flat are super-critical fits. Camlock pins not quite as much.
:D
 
I think you mean D1-2?

Here's a listing:

AMERICAN LATHE SPINDLES SPECIFICATIONS

Natchurly, you have a "3-D model" right in front of you.. or you would not have the need! EG: It has to FIT your lathe. No other, actually.

Seriously. "Job One" is to make a fitting-dummy duplicate as a test gage for the "many" backplates.

Taper & flat are super-critical fits. Camlock pins not quite as much.
:D

Hi again guys

For the past few days I’ve been doing research in regards to this lathe. Can anyone point me in a direction of a video showing disassembly and reassembly of lathe. I’d like to clean the lathe up and replace the belts. But I can’t figure out how to get the lathe apart to change belts any help would be appreciated
 
Hi again guys

For the past few days I’ve been doing research in regards to this lathe. Can anyone point me in a direction of a video showing disassembly and reassembly of lathe. I’d like to clean the lathe up and replace the belts. But I can’t figure out how to get the lathe apart to change belts any help would be appreciated

Ummhhh... "video"?

These lathes sorta "pre-date" the media age..

Even the chariot race scene in "Ben Hur" was a staged reproduction, from a scene in fiction written two thousand years after the era.. so....

As with that movie, you'll have to expect to adapt from research and extrapolated generalizations?
:)
 








 
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