#7 Brown and Sharpe taper, whats the deal?

I have a bridgeport with a #7 Brown and Sharpe collet taper. I also just got a new set of #7 B&S collets of all 7 sizes from little machine shop. And they seen of very high quality, and they look brand new.

So whats the deal? I thought there were no mills at the time ground with a #7 B&S taper, yet a ton of people sell NEW collets and end mill holders for them.
Including LMS, traverse tools, Victor machine, tools4cheap, etc.
Are there any mills currently being made with that taper? Are the collets and endmill holder new old stock just kept in very good condition?
Thanks guys!
Here are a few links if some of you are interested in getting come collets.

Tools4cheap LLC Online Machine Shop Tooling Store: Brown & Sharpe #7 Collet Set -7pc,Brown & Sharpe Taper Tooling

End Mill Arbors | Travers.com

7 Brown and Sharpe and 9 Brown and Sharpe collets for milling machines.

Collets, 7BS Set of 7 - LittleMachineShop.com (very good quality on these, although I have not tried the yet)

Spyderedge said:

and they look brand new... Are the collets and endmill holder new old stock just kept in very good condition?

Click to expand...

They look new because they are new. They are made in India or China and are not new old stock

B&S #7 is/was a popular taper for smallish dividing heads and rotary tables.. Not just mill spindles..

Many of which get sold, without the round tooling in a drawer somewhere...

Since tool holders are a wear/consumable part. There must be enough demand to produce them still.

My M Head is so equipped, I only had to make a boring head arbor, rest of the normal tooling was available..

My Japanese copy of a B&S 0 dividing head has a 7 B&S spindle and I bought a set of collets for it back around 1974. If you want more expensive collets that are made in the USA, Hardinge still makes them.

Larry

Spyderedge said:

(very good quality on these, although I have not tried the yet)

Click to expand...

Until you have tried all of them to make sure they go into your spindle without difficulty, grip whatever you're holding in them with the necessary clamping force, spring back by the correct amount to allow tooling to be inserted and withdrawn, and have measured their runout when installed, all you can say is they look shiny and new. That's great, but shiny tells you nothing about whether or not they are of "very good quality".

opscimc said:

Until you have tried all of them to make sure they go into your spindle without difficulty, grip whatever you're holding in them with the necessary clamping force, spring back by the correct amount to allow tooling to be inserted and withdrawn, and have measured their runout when installed, all you can say is they look shiny and new. That's great, but shiny tells you nothing about whether or not they are of "very good quality".

Click to expand...

You are right, but I can almost guarantee they will have less runout than the collets from when the machine was made, 65 years ago, that were abused in a production shop.
I'll measure the runout with a 3/8" dowel pin in the old and new collet and report back.

I've been given the suggestion to buy an E32 collet chuck to replace the #7 B&S collet setup I currently have. Has anyone else done this?

https://www.amazon.com/gp/aw/d/B07G...AABAAAAAGAqbX5yYXcAAAAA+4kUEk/7iMGR3xPcX6iU&#

I've looked at those as well. I just haven't pulled the trigger yet as I have a decent set of BS7 tooling for my M-Head. Plus, it wasn't so pricey when I first looked at them. If you do purchase it, let us know your impressions on quality and runout etc. Thanks.

Best Regards,
Bob

It looks like a good option. I have two other machines I'm trying to set up for the same ER32 collets. I've got an old Greaves Cincinnati and a Monarch lathe. I believe the Greaves is a #50 taper. The Monarch has a D1-6 back plate. I've contacted a California manufacturer to see if they can accommodate the other two machines.

If you have a Bridgeport with an M-head,
let me give you something to look out for.
I have one, with the #2 Morse taper,
about 5/8" per foot. Very similar to the
#7 Brown Sharpe taper, which is about 1/2"
per foot. Anyhow, if you use split collets
in the milling machine spindle, the nose of
the spindle well wear and get bell mouthed.
So what perhaps you are thinking ?!?
Well with collets, it is not a big deal for
the most part. But if you use anything that
has a solid shank, like a boring head, then
you have a situation where the solid tapered
shank only seats and contacts on the SMALL
end of the taper. The large end at the nose
of the spindle has some clearance, because
the spindle is bell mouthed. This WILL cause
the boring head to chatter, because it in essence
has another couple of inches of stick-out from
not seating at the front of the spindle.
This is the case with my M-head machine.
For years I could never figure out why I could not
bore with it. Even .oo5" cuts resulted in chatter
so bad it was ridiculous. That is until I figured
out the bell mouthed spindle was causing the
aforementioned situation. So one thing I tried
was to take a strip of paper and cut a 1/2" strip,
I think I used the top of a yellow sticky note,
and wrap it around the large end of the taper shank
of my boring head. This was right in the area where
the spindle taper was worn oversize. Making sure
the paper did not slip, I installed the boring head
as normal, and gently snugged up the drawbar.
Well that did it. I was finally able to bore with NO
chatter. After years of not playing it it, the thought
to check the taper just came to me one day.
So re-grinding the spindle taper is the ultimate answer,
but for now I have one wrap of thin strip of sticky note
paper wrapped around the top shank of my boring head.
I thought of maybe just turning the 2MT shank down to
1/2" straight shank, and just using a 1/2" collet to
mount it. I don't think that would chatter either.
I hope my story helps you or at least prevents you some
frustration with your mill.

--Doozer

This is zombie thread.
However...why add stickout to the spindle if you already own the native spindle tooling?

I know Deckel FP1 and FP2 mills
have an adapter from their native
spindle, of wither Morse #4 or
NMTB 40 to some 20mm collets.
I removed the collet adapter
from my Deckel FP1, and the
bore taper was ground glass
smooth. The taper adapter had
protected the spindle taper
all these years. So for a long
term machine, I guess the purist
would use a collet adapter to
prevent wearing the spindle taper
from inserting and removing
collets a million times.
Notice on the spindle of
Hardinge lathes, the 5C collet
in the spindle leaves 3 little
unworn marks, where the slits
of the collet line up ?
It just goes to show the amount
of wear even a hardened spindle
can receive over time with using
collets in the native bore.

--Doozer

tkief said:

I've been given the suggestion to buy an E32 collet chuck to replace the #7 B&S collet setup I currently have. Has anyone else done this?

https://www.amazon.com/gp/aw/d/B07G...AABAAAAAGAqbX5yYXcAAAAA+4kUEk/7iMGR3xPcX6iU&#

Click to expand...

#7 B&S has about the same grip as Are-Ate. #9 B&S has a lot more grip than Are-Ate.

Soo...

If you HAVE decent # 7 BS (or #9, my case), my ER 20 and ER 40 mainly let me use a spanner right in front of my face and NOT have to climb up on a stool or wander round the back to mess with a drawbar. "As often".

I have all of 40-taper, 4 MT, 2 MT, #9 B&S, an straigth-shank ER HOLDERS. So I also have "extra' # 9 B&S and "native" 40-taper collets for their shank sizes - which also fit the Chandler-Duplex heads or the Precise die grinders - same straight shank sizes.

Even so, the ER are NOT the first ones I reach for. Basically, I have them to allow very few collets with very wide clamping range to serve odd sizes, ALL machines in my shop. If/as/when I don't have a side-lock holder that fits the need.

So yes, cheap, cheerful, lotta "goodness", but far from the "only" solution.

Ex: I also have VS and S series PDQ-Marlin for #9 and 40-taper, each with a goodly selection of side-lock holders & a drill chuck. Much nicer! They take silly-small free daylight to swap tooling.

So the ER (and TG-100..) don't see much actual use... and the NEW set of # 9 B&S collets mostly hold down a cabinet drawer, manual drawbars the PITA they can be.

2CW

Thanks for your input! I read it to say you aren't really a fan of the idea.
Here's a little background on my situation. I'm employed by a glass container company employing 250-300 people. I'm the only machinist and one of the few people with any knowledge of what I do. If you aren't familiar with this industry let's just say it's very primitive with few resources. I know people who have better setups at home.
The Bridgeport I'm speaking of is very antiquated and was probably purchased used when they acquired it long before my time. I don't use it for boring and have a very limited supply of tooling. I have a Greaves Cincinnati for boring.
I've never been in the situation of purchasing as I was able to get by with what I had. I'm at a point now where I have to come up with a solution.

I have one of the ER32 adapters and it is handy, but two things to be aware of: with it you lose some daylight under your spindle and possible some visibility of work, but also adding an adapter adds the possibility of run-out. Running tools directly from the spindle via a collet is going to produce the least potential of run-out.

One other issue concerning all the Chinese collets: The biggest problem I have with tooling and machines coming from over there is consistency. One guy might buy a tool and it works out great. Another guy buys the same tool and it's a sloppy mess. Quality control is one of the easiest things for a factory to drop in the name of saving money, and when you deal with a global economy and don't have any control over the actual manufacturing, you don't know if your supplier switched to a cheaper factory and didn't tell you.

I've bought my share of Chinese tooling and it's hit and miss. I see them more as a means-to-an-end until I can find something better, which most often comes in the form of good used name-brand stuff.

thermite said:

....Ex: I also have VS and S series PDQ-Marlin for #9 and 40-taper, each with a goodly selection of side-lock holders & a drill chuck. Much nicer! They take silly-small free daylight to swap tooling.



2CW

Click to expand...

The first time I saw a PDQ setup was on an actual Portage HBM.
We had one at the Michelin plant where I worked. The captured triangle
design is pretty cool. I kinda wish my Pratt Whitney 2A jog bore
had PDQ type tooling.

Side note, I remember one odd thing on that Portage HBM.
When you wanted to rapid an axis, you had to shift out of slow feed,
then into reverse, then the rapid would move you forward.
If you ONLY just hit rapid, it would rapid in reverse.
I think Cincinnati Greaves machines might be like that too,
with their foot pedal rapid. The old machinist that used to run it
would have both hands on a set of levers, he looked like a truck driver
shifting a Mack quadraplex.

-Doozer

I have a ER20 to #7B&S collet adapter that I made for my M head. It has worked well for me other than the reduced space under the spindle.

Doozer said:

If you have a Bridgeport with an M-head,
let me give you something to look out for.
I have one, with the #2 Morse taper,
about 5/8" per foot. Very similar to the
#7 Brown Sharpe taper, which is about 1/2"
per foot. Anyhow, if you use split collets
in the milling machine spindle, the nose of
the spindle well wear and get bell mouthed.
So what perhaps you are thinking ?!?
Well with collets, it is not a big deal for
the most part. But if you use anything that
has a solid shank, like a boring head, then
you have a situation where the solid tapered
shank only seats and contacts on the SMALL
end of the taper. The large end at the nose
of the spindle has some clearance, because
the spindle is bell mouthed. This WILL cause
the boring head to chatter, because it in essence
has another couple of inches of stick-out from
not seating at the front of the spindle.
This is the case with my M-head machine.
For years I could never figure out why I could not
bore with it. Even .oo5" cuts resulted in chatter
so bad it was ridiculous. That is until I figured
out the bell mouthed spindle was causing the
aforementioned situation. So one thing I tried
was to take a strip of paper and cut a 1/2" strip,
I think I used the top of a yellow sticky note,
and wrap it around the large end of the taper shank
of my boring head. This was right in the area where
the spindle taper was worn oversize. Making sure
the paper did not slip, I installed the boring head
as normal, and gently snugged up the drawbar.
Well that did it. I was finally able to bore with NO
chatter. After years of not playing it it, the thought
to check the taper just came to me one day.
So re-grinding the spindle taper is the ultimate answer,
but for now I have one wrap of thin strip of sticky note
paper wrapped around the top shank of my boring head.
I thought of maybe just turning the 2MT shank down to
1/2" straight shank, and just using a 1/2" collet to
mount it. I don't think that would chatter either.
I hope my story helps you or at least prevents you some
frustration with your mill.

--Doozer

Click to expand...

It was the answer I needed, thank you very much. I don't think I have a bell mouth problem, rather the '54 or earlier spindle, based on the original 3/4" motor shaft, is bottoming out the 3" Chinese Brown & Sharpe #7 collet. The 1/2" of Post-It seated the collet with a full 1/2" protruding from the spindle. Full contact! It's working great though a friend has suggested semi-permanently mounting the 1/2" with an ER adapter. Have plenty of Z for what I do, so no loss there. Just more tooling to buy.

Shiseiji said:

It was the answer I needed, thank you very much. I don't think I have a bell mouth problem, rather the '54 or earlier spindle, based on the original 3/4" motor shaft, is bottoming out the 3" Chinese Brown & Sharpe #7 collet. The 1/2" of Post-It seated the collet with a full 1/2" protruding from the spindle. Full contact! It's working great though a friend has suggested semi-permanently mounting the 1/2" with an ER adapter. Have plenty of Z for what I do, so no loss there. Just more tooling to buy.

Click to expand...

Pratt & Whitney made two spindle machines that took 9B&S and 7 B&S. These were mills / profilers