#30 taper Series 1 Bridgeport

[DFMiller]

I am looking at a Series 1 bridgeport that has no tooling. It is supposed to be #30 taper quick change. I am having some trouble finding definative information and pictures of what will stick in the hole. Any help is appreciated.
Dave

[HTRN]

I can tell you from experience, it's NMTB 30. It isn't cheap. Take a look on ebay as they're usually somebody who's selling some.


HTRN

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This Old Shed

[precisionworks]

Most older BP's are R-8 spindle taper for R-8 tooling. Pretty much everything pre-1975 (before wide use of CNC).

Newer machines are optional with either:

#200 Universal spindle taper for Universal #200 Kwik Switch or

#30 ISO taper for Erickson Quick-change #30 ISO

All the tooling supply houses carry these. The confusion is that they are sometimes listed as "30 taper" or "30 ISO" or "30 NMTB". Here's a link that explains it briefly: http://www.cox-internet.com/drspiff/...ets/tapers.htm



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Barry Milton

[DFMiller]

Thanks Guys,
I was not sure whether all three where the same. Now I have a warmer feeling. I have heard the stuff is expensive but had not found any pricing yet.
Thanks
Dave

[lsloth]

What is the advantage of NMTB 30 over R8?

[precisionworks]

If you set an R-8 shank next to a 30 NMTB, you'll see that the 30 has a larger and longer side-bearing surface area. Most milling operations (like slotting) involve heavy side-loading, so the increased area spreads these forces out.

On R-8 tooling the bearing area is many times smaller, so each square inch of surface has a much higher loading.

In a perfect world it wouldn't make any difference since all radial loads would be 100% transferred to the quill bearings. But all tooling has some amount of tolerance. If your quill taper is slightly on the plus side and your toolholder is slightly on the minus side you'll have contact only in an extremely small area. Sometimes you'll see this as a thin line around the circumference of the toolholder indicating where the contact is.



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Barry Milton

[dsergison]

"What is the advantage of NMTB 30 over R8?"

#1 rigidity
#2 shortness of tool holder.

shortness making changing tools require less space.

30 taper replacement spindles are available. it may be that your machine was updated at some point.

decent 30 taper tooling isn't real expensive, relatively. (but there arent many el-cheapo discount sets either.)

[DFMiller]

Barry,
Thanks for the information.
after another vist to the machine it is a
#200 Universal spindle taper for Universal #200 Kwik Switch. Now we have to find a good source for it. If anyone knows a source contact me .
Thanks
Dave

[precisionworks]

Dave,

Here are some links for Universal #200 KS tooling:

http://search.ebay.com/kwik-switch_W0QQ

http://www.collistool.com/general.htm

http://www.workholding.com/univkwik_...g_features.htm

http://www.toolingsystems.com/univ/k...rs/kwiknmm.htm

And finally, the company that makes them: http://www.toolingsystems.com/



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Barry Milton