New to me SB Mill, need options for tooling

BGHansen said:
Looks like you have this model (attached PDF). The picture below is from page 7. Part# 4 is a collet chuck. Part# 3 are collets which according to the parts list were 3/8", 1/2", 5/8" and 3/4". I got these from vintagemachinery.org. It sure looks like an NMTB 30.

CHECK OUT THE PIN UP GIRL ogling the mill (from one of the sales fliers)! I can't recall my wife ever looking that lovingly at any tools in my shop.

Bruce


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Thanks!
Same here, I just get puzzled looks.

Also looking for operating manual. Did a search for that, only found parts list.

As it stands, I would need to measure the collet ID, and buy only end mills with that sized shaft?
Is the NMTB a respected setup? What else would work for tool holding in this design?
 
Found another download on Vintage Machinery. Here's the set up and instruction manual though the scan is really light.

Bruce
 

Attachments

  • South Bend mill set up.pdf
    2.3 MB · Views: 11
I don't own a machine with the NMTB 30/40/50 spindles but the machines I've seen them on are metal-hogging wonders. Seems like Vertical mills favor R8, horizontal and CNC machines use the NMTB. Those drive lugs must make a lot of difference delivering torque from the spindle to the tool holder.

You may have to make collets or maybe find some Weldon-style holders that have your collet size. I'm thinking there may be a straight shanked 3/4" (if that's your collet size) to a 1/8", 1/4", 3/8", etc. hole in the other end with a set screw to hold the end mill.

Bruce
 
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Manual says it’s a No. 30 Milling Machine Taper. The face of the spindle has four bolt holes tapped 3/8”-16 for attaching milling cutters
 
I could not get the manual to download, but it appears that, looking at the parts picture thAt there are two angled setscrews, one on each side of the spindle , that when backed off, allow the collet accessory to be removed, they bear against flats machined into the collet body, hence there being no need for a drawbar. It is very likely a modified 30 taper, the holes in the driving lugs have the setscrews in them.
My Fray vertical mill has the 30 taper spindle, but not the setscrews, but instead has a drawbar.
 
Is metal hogging wonder a good thing?

Not sure I understand the last paragraph....
BGHansen said:
I don't own a machine with the NMTB 30/40/50 spindles but the machines I've seen them on are metal-hogging wonders. Seems like Vertical mills favor R8, horizontal and CNC machines use the NMTB. Those drive lugs mush make a lot of difference delivering torque from the spindle to the tool holder.

You may have to make collets or maybe find some Weldon-style holders that have your collet size. I'm thinking there may be a straight shanked 3/4" (if that's your collet size) to a 1/8", 1/4", 3/8", etc. hole in the other end with a set screw to hold the end mill.

Bruce
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I like the 30 taper spindle because it does not require nearly as much vertical clearance to exchange tool holders as compared to R-8, plus the positive drive with the driving keys that do not shear off like the R-8 tiny pin up in the spindle bore. Both my Fray vertical and my #2 Brown & Sharpe horizontal with vert. attachment use 30 taper in the vertical mode, and with a adaptor, I can use the 30s in the #40 horizontal spindle.
 
I had a Kondia vertical mill which used 30 taper tool holders a long time ago.
Had the basic fractional sizes of end mill holders and it was a terrific machine.
The advantage of tool holders over collets is the cutters are held in place in a rigid manner by set-screw and will not feed out when pressed with heavy cuts.
 
So where is a good place to get starter set of collets and end mills for 30 taper?
 
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