Issue with NMTB30 tooling I just bought.

Superburban said:
Does your machine use that grove to hold the tool? If so, you may have one of the other nm tapers. Cat, iso, and 10 million other names.

http://www.tools-n-gizmos.com/specs/Tapers.html

https://en.wikipedia.org/wiki/Machine_taper
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Thank you. This looks like an excellent reference. From what I read so far, it would appear that what the previous owner told me is ass-backwards. But I need to investigate more, tomorrow.

*EDIT:
It's also equally possible that I remembered his words ass-backwards. I am pretty sure though that he said anything I order must be "NMTB30" and not QC30 or any other 30 taper, because some might work and some might not, but NMTB was the only one guaranteed to work.

EDIT2:
Just realized I completely neglected to answer your question. YES. The groove is used to hold the tool.
 
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benmychree said:
You talk about 30 and 40 tapers in the same breath; which is it???
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The machine spindle is (per what I was told by the previous owner) NMTB30. The part I bought was an ER40 collet holder, with NMTB30 taper on top so that I can use the ER40 collets I already have.
 
derf said:
you using a Ericson spindle?
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I have no idea. It's a 1988 Lagunmatic 110 CNC. I don't know what it came with from the factory or if it's still stock. The machine has a lot of modifications.
 
I think its a type of right of passage with these machines, that we all have to have several tool holders that look the same, but will not work. I have collected a bunch of xxxx50 tool holders for my Van Norman. I now have some that have a 7/8 thread, instead of the NMTB spec of a 1" thread. 2 that I think are metric, as they will not thread more then 1 thread or so (yea, never walked to the other side of the shop to get the thread gauge). a couple of Cat50.


strantor said:
EDIT2:
Just realized I completely neglected to answer your question. YES. The groove is used to hold the tool.
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From what I understand, the true NMTB spec, is only the taper, and the nub and thread at the end. Back in the 20's, when the NMTB spec was decided, they had no thought of a quick change yet.

Maybe if you post up a pic or two, and some information about your machine, someone will have the info you need to avoid this in the future.
 
Sorry I am slow to keep up. Working 2 jobs and neither of them involves machining.

I checked out my spindle and it has some writing on it which I can't quite make out:
20180207_180204.jpg
Looks to me like
ETC
QC300CLN
Not quite sure but I suspect that means Erickson Tool Company, and the part number hints at QC30.

Since I'm not positive what spindle I have, I didn't feel comfortable asking for a refund. Instead I decided to try and make it work. I put the collet holder in my Logan 9" lathe and started turning it down to the proper dimensions.

I wasn't sure how well I was going to do, considering it's pretty hard steel and a hellacious interrupted cut. With a carbide insert and over an hour of my time, I did manage to make it work. Not pretty, but functional.

20180207_194924.jpg

Here's a comparison. The one I turned next to the one I haven't touched.

20180207_195011.jpg
 
According to this post, the part number is almost certainly QC30QCLN, which is indeed Erickson QC30.
Everything I thought I knew was wrong :dejected:
 
Now you know what I was getting at......the tapered parts are the same, the Erickson has a smaller flange. I purchased several from Grizzly and turned down the flange. Later I added a power draw bar and eliminated the nut so it no longer makes any difference.
I don't know why they called it an Erickson "Quick change", there's really nothing quick about it.......but a power draw bar makes it quick.
 
derf said:
Now you know what I was getting at......the tapered parts are the same, the Erickson has a smaller flange. I purchased several from Grizzly and turned down the flange. Later I added a power draw bar and eliminated the nut so it no longer makes any difference.
I don't know why they called it an Erickson "Quick change", there's really nothing quick about it.......but a power draw bar makes it quick.
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Power drawbar is faster than this for you? I'm still not Sure we are talking about the same thing. I don't have a drawbar at all. I put a tool in, turn the nut 1/4 turn, and done. I don't see how any kind of drawbar could be faster.

I couldn't put a power drawbar on my mill anyway, because there's no hollow path through the center of my spindle.

P.S. the flange OD was not the problem on the tool in question. The problem was that there was no gap on the other side of the flange. But I do know what you're talking about now, as I did receive another tool today that won't work because the flange 1.98" wide. I have it set up in the lathe and will turn it down tomorrow.
 
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