Pratt&Whitney

Looking for a compound for a Pratt And Whitney model b lathe looks like one off a model c might work as well Thanks Devin

Probably need to say what size. There were 12/13", 16" and 20" - NEVER MIND I see you user name is DESCRIPTIVE

Here is an older catalog scan - thanks to Greg Menke for hosting this to me

http://pounceatron.dreamhosters.com...ttwhitney-circular402-model-b-lathes-1936.pdf

j

I have the newer model 16" P&W. most of it looks the same as shown in John's manual.I also have the owners and parts manual. My manuals are newer than the lathes shown and they are of the later version with ball and roller bearings. My manuals show everything on the previous round head though mine is the square head. In the rear of the manuals changes are noted as well as notes to look at a specific page for the upgrade are listed in the pages of the round head version. It seem P&W didn't want to produce a new manual just up-date the older one. I don't see much difference in the compound except the addition of 2 rather large oil cups on either side of the feed handle. Unfortunately they do not have dimensions so I have no idea if one will fit the other. However from what I see P&W didn't change much just up-graded so it's very possible the C compound will fit your B as long as the lathe swing size is the same.

The issue could be more height. The "B" has a SECOND CROSS SLIDE - to allow the T/A to work. The "C" does not, making the "C" compound rest TALLER

In other words, if the "C" fit the "B", you may have a rig TOO TALL

One of these days I'll get around to scanning the 12" B brochure

My compound has been changed at some point in its 76 odd years it functions fine but is way to big, from the saddle to the top of compound is 2.75” which only gives me 13/16 to center and limits my tools to 3/8 or smaller. Mine has a base of 7” and has a bolt circle of 5.970” and has a 2” centering stud hoping someone on here would have a parts machine, that might part with compound. From pictures I’ve looked at a model c looks the same my is a 12x30 model b, but from pics a 16x54 is still smaller than what mine has on it. Thanks Devin

The FIL has an early 13" Model B and might be interested in some internal parts when he pulls the spindle out, but they don't seem to come up around here, and shipping doesn't make sense for a parts machine. Of course, the 12 wouldn't be same on the spindle, and the single tooth clutches are probably abused on every donor machine - those are easy to fix once out anyway, so I'm not looking too hard. So I cannot offer much hope, but thought I'd mention it in case somebody is on the verge of parting one out, but needed a little more incentive than the compound. Actually, when the spindle locked up on him, I briefly thought it may have to become a donor machine itself, but the ways and apron are too nice, so he's determined to fix it and maybe take care of those single tooth clutches while it's that far apart.

Now that gets me thinking further....on the real odd chance of something rough enough to become a donor, but having a good compound (for the OP in this thread) and a good head: Is the head on a 12" a drop in replacement for the 13". That might solve the limitations in chucks for the FIL too.

johnoder, you mentioned the extra cross slide in the model B's. When I first saw that on the 13, I thought it a most elegant approach for taper. I don't think it had ever been used on that one, but I loosened the locks, sprayed thoroughly with penetrating oil and had it feeling smooth - why did they go away from it? Cost? Clearance?

why did they go away from it?

Click to expand...

Likely because the competition went with TELESCOPING screw - way less parts and expense