Is BT30 compatible with NMTB 30?

My understanding is the taper is the same, but the drive dogs and retention knob are entirely different, and it would be very difficult to convert from one to the other.

Jon

Thanks Jon. Did I mention that your PPMC is a great product?

and the draw bolt has a different thread and size. Some are metric

Gunner

I am the Sword of my Family and the Shield of my Nation. If sent, I will crush everything you have built, burn everything you love, and kill every one of you. (Hebrew quote)

Since he has a Quick Change NMTB30 spindle with a retention collar instead of a drawbar, can he use BT30 in the spindle with a suitable BT30 drawbar, or will the Quick Change collar get in the way?

The *taper* is the same -- but the flange (which your quick-change spindle depends on) is quite different.

So -- no *you* can't use them -- unless you remove the quick-change locking ring, remove the draw stud, and make a drawbar to fit the thread which the draw stud uses.

I've used BT-40 in a NMTB 40 spindle -- but with a special drawbar and no quick-change nose. (This is on an old Nichols horizontal spindle mill.) I've also made collars for the back of the taper to accept existing drawbars for that machine.

If you can get *one* cheap -- get it, so you can learn the difference. But don't bid on it expecting to use it.

Enjoy, DoN.

Oh. The Quick Change Collar will definately be in the way.

Gunner

I am the Sword of my Family and the Shield of my Nation. If sent, I will crush everything you have built, burn everything you love, and kill every one of you. (Hebrew quote)

Indeed. My Gorton Master Mill is NMTB 30. I have a fair collection of NMTB, CAT and BT 30 holders..and 3 different draw bars that are marked by different color spray paint so I know which goes with what

They all fit the spindle nose, but all require different draw bars..

Gunner

I am the Sword of my Family and the Shield of my Nation. If sent, I will crush everything you have built, burn everything you love, and kill every one of you. (Hebrew quote)

Absolutely so!

I've got one BT-30 (or was it a CAT-30) which I tried turning the flange thickness down on the lathe to match the NMTB-30 flange thickness -- but I haven't dared to try it yet.

Enjoy, DoN.