Hardinge BB4 BB2V Mill - Spindle Taper and Collet Specifications

[ViKiNG Max]

I recently purchased a small Hardinge milling machine that has both a vertical head BB2V and a horizontal head BB4

The machine came with a small selection of imperial collets for the vertical head. From my research C (and similar) Collets these are BB2V collects with 7/16 20 drawbar. The vertical head has a different taper which from my research is 4C with 15/16 28 drawbar. I have both drawbars. What is puzzling me is that the horizontal spindle appears to have two tapers which without good measuring gear look like 10 degree per side and 5 degree per side. This is what also appears to be shown from a Hardinge publication cross section that I found on the net – marked up with a red arrow in the image. The short 10 degree taper is 4C but I have not been able to find any information on the longer 5 degree taper. I know that these machines were commonly used horizontally with a 1” arbour.

1. Are there two different tapers in the horizontal head. 4C and a different taper for the 1” arbour? If so can someone point me to specifications for 5 degree taper
2. Can anyone please identify the age of the machine from the serial number on the horizontal head 47-22243?
3. Does the small plate on the main casting mean anything D.P.L.51. ?

The reason for the questions is that I live in a New Zealand which is metric and I am unable to use the machine until I make metric collects and 1” arbour as the collets are uncommon especially metric sizes.

 

[rke[pler]

Some discussion here:

https://www.practicalmachinist.com/...-mill-horizontal-vertical-260310/#post1972263

The 4C for the BB4 should be easy, but metric 2VB collets are going to be scarce as hen's teeth. If you can find them at all they're likely to be local to you, I've never seen one in the US and only see the imperial ones a few times a year. In the end you might have to bite the bullet and pay hardinge $280+ for a single metric collet in the most common size you need.

 

[jim rozen]

This absolutely needs to be put in the hardinge sub-forum where Larry can see it, so he can weigh in on possible sources. He's the go-to guy on this.

 

[L Vanice]

I bought my first Hardinge lathe, a Cataract 47 with the chasing attachment, in 1978. I knew nothing of 4C collets and the lathe had no drawbar, tailstock or slide rest. I made a cast of the spindle taper to see if it had a Morse taper for a center. Eventually, I figured out the 4C collet and found that the second taper behind the collet nose was just a feature to make inserting a collet easier. For their lathes, Hardinge made solid male centers with 4C arbors and a separate dog driver that mounted on the outside of the spindle nose. I made a drawbar from solid steel bar with a knob made from a caster with a hard plastic wheel. I made an adapter and fitted a new Myford Super 7 tailstock ordered from Buck & Ryan in London. I also bought a new Myford ML8 slide rest and fitted it to the Hardinge. I have never seen a metric 4C collet, though Hardinge will make them new.

Serial no. 22243 was built in 1944. Your vertical head should also be numbered on one of the round belt access plates.

D.P.L. 51 is an original or second owner's machine inventory tag which may give a clue to the old owner but has nothing to do with Hardinge.

I currently have lots of new and used 2VB (they are not called BB2V) collets, but have never seen one that had anything other than an inch by 64ths order hole (1/16" to 1/2" by 64ths). Forty years ago, I sold a BB2V mill to a clockmaker. I had no spare 2VB collets, so I made an end mill holder to get the new owner able to get started doing some work. I simply copied the dimensions of the 2VB collet in solid steel with an extended nose bored to 1/2 inch with a set screw to hold the cutter. It would be pretty easy to make those in any metric size. If you want to get fancy, make one bored and threaded for ER collets. You can get ER collet chucks with various inch and metric straight shanks that can be mated to a 2VB collet or an arbor you make yourself. I have a 5/16" 2VB collet and it would not take much lapping to make it into an 8 mm.

Back in the day, Hardinge made 4C cutter arbors for any standard screw slotting saw or horizontal cutter, not just 1 inch. They can be made from a 4C plug chuck and I have a few unused spares. Below are photos of three old 4C cutter arbors and a new 4C plug chuck.



Yes, Jim, I read the General section thread titles.

Larry

 

[jim rozen]

Well, this is so much more so a refined place to discuss those machines!

 

[ViKiNG Max]

Hi Larry

Thank you so much for the informative reply and also for including photos of your arbours. This is a big help

What got my attention about the second taper is that it has a ground finish, but I am pleased that it is not a machine taper as I will not need to make tooling to fit it. This answers this question which is what I was most curious about

Following your suggestion about serial number for the head, I checked the round covers and there are no serial markings on them. The only characters are on the inside are small and stamped "B1" which I would guess are an identification for production to pair them to the correct machine? I have had a thorough look over the head and can't see a serial number anywhere.

I will make heat treated 4C and 2VB collets in metric sizes. As I can make them it means that I can make any size I want and some spare soft ones at the same time. Using ER collets is a good idea but I am reluctant to use an ER setup as it will give away valuable height and as it really is a small machine I want all the envelope I can get

 

[illumiquest]

I bought my first Hardinge lathe, a Cataract 47 with the chasing attachment, in 1978. I knew nothing of 4C collets and the lathe had no drawbar, tailstock or slide rest. I made a cast of the spindle taper to see if it had a Morse taper for a center. Eventually, I figured out the 4C collet and found that the second taper behind the collet nose was just a feature to make inserting a collet easier. For their lathes, Hardinge made solid male centers with 4C arbors and a separate dog driver that mounted on the outside of the spindle nose. I made a drawbar from solid steel bar with a knob made from a caster with a hard plastic wheel. I made an adapter and fitted a new Myford Super 7 tailstock ordered from Buck & Ryan in London. I also bought a new Myford ML8 slide rest and fitted it to the Hardinge. I have never seen a metric 4C collet, though Hardinge will make them new.

Serial no. 22243 was built in 1944. Your vertical head should also be numbered on one of the round belt access plates.

D.P.L. 51 is an original or second owner's machine inventory tag which may give a clue to the old owner but has nothing to do with Hardinge.

I currently have lots of new and used 2VB (they are not called BB2V) collets, but have never seen one that had anything other than an inch by 64ths order hole (1/16" to 1/2" by 64ths). Forty years ago, I sold a BB2V mill to a clockmaker. I had no spare 2VB collets, so I made an end mill holder to get the new owner able to get started doing some work. I simply copied the dimensions of the 2VB collet in solid steel with an extended nose bored to 1/2 inch with a set screw to hold the cutter. It would be pretty easy to make those in any metric size. If you want to get fancy, make one bored and threaded for ER collets. You can get ER collet chucks with various inch and metric straight shanks that can be mated to a 2VB collet or an arbor you make yourself. I have a 5/16" 2VB collet and it would not take much lapping to make it into an 8 mm.

Back in the day, Hardinge made 4C cutter arbors for any standard screw slotting saw or horizontal cutter, not just 1 inch. They can be made from a 4C plug chuck and I have a few unused spares. Below are photos of three old 4C cutter arbors and a new 4C plug chuck.

View attachment 344551 View attachment 344552

Yes, Jim, I read the General section thread titles.

Larry

I was wondering if you have the measurements for the 2vb collets. I can’t seem to find the taper angle anywhere online.

 

[stephen thomas]

I might have some non-inch 4c's but they would be old and beat.

That said, AFA something useful, how about making a 2VB shank with ER16 female nose. Or possibly ER 20. (not sure of 2VB gage line dia). That could be gotten to fit up in your machine with no more extension than the closer nut. Either make(turn)/harden/ grind, or search a suitable close commercial shank, and re-grind from solid. Though that would leave adding the drawbar threads as a potential difficulty. Some commercial arbors are just soft enough in the center to tap with sharp HSS, though. Or could be locally annealed with the other end in a bucket of water.

smt

 

[spaeth]

Max,
I have three Hardinge 2BV Collets that appear to be new or very gently used. (2) 3/16" and (1) 5/16". Might be easier to gather up some imperial cutters than metric collets. 35.00 each + mail. spaeth