What is that on top of the mill's head? Drawbar or a place to mount encoder?

Same base spindle part before grinding the particular taper and whatnot?

Reply to
Pete C.
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That's why I'd double check he doesn't have a QC adapter with a taper 30 or taper 40 spindle. My machine came with an adapter that had never been removed. I do know they also make QC spindles too.

Karl

Reply to
Karl Townsend

Sorry, Karl, I do not understand. Do you have a power drawbar on top?

Do you also have an encoder on the spindle?

Where does your collar go? I am sorry, I am confused a little.

My original idea was to just add a US Digital or some such encoder on top by adding a little shaft protruding up from the spindle.

Sorry that I am a little slow this afternoon.

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So you are saying, I could have a power drawbar AND and encoder? Right?

i
Reply to
Ignoramus6705

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It has a QC spindle, yes, but those QC tools have a thread and could be used with a drawbar, IIRC.

i
Reply to
Ignoramus6705

That mill was available with a number of spindle options.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Reply to
Gunner Asch

My mill has a QC-30 spindle and a collar to hold toolhonders in place.

The toolholders are threaded on top and I guess could be drawbared too.

I am not sure how this QC-30 spindle is compatible with "Cat 30" or "NMTB 30" tooling. eBay and liquidations are flooded with that tooling and I wold love nothing better than to be able to use it.

i
Reply to
Ignoramus6705

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First be double damned sure you haven't got an NMTB spindle with a QC30 adaptor. Get a light or something down that top hole and make sure there isn't a bolthead at the bottom of the hole. I'm not the expert on the particular machine so you may need others' help here.

If you do have an NMTB spindle, I'll go to the trouble to take mine apart and photo it. I must say, I was purty clever here cause I wasn't about to lose the power drawbar. If you don't have an NMTB spindle you got that whole spindle shaft to mount an encoder and it should be a piece of cake

Karl

Reply to
Karl Townsend

Id love to have both NMTB 30 and 40 tooling with drill chucks attached, not simply stuck in the hole.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Reply to
Gunner Asch

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I think that he does have the NMTB spindle. I know that mine is clear all the way through and is NMTB 30 at the bottom. (Mine is a Series-I from back in the BOSS-3 days (steppers and LSI-11 CPU).)

IIRC his is a Series-II (Larger machine, and servo motors from the factory.)

And his does not have a power drawbar -- or *any* drawbar. Nor does mine.) Is there some load threshold at which you need to add a drawbar to the NMTB 30 quick-change holder -- such as perhaps when using a boring/facing head?

I would be interested in seeing the photos as well if you do take them. But I could not receive them in e-mail. Do you have a web site -- or could you put them in the dropbox ()?

Thanks, DoN.

Reply to
DoN. Nichols
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Yes -- they could.

What you have is a quick-change nosepiece which *expects* the NMTB-30.

The *taper* in the CAT-30 is the same (and actually happens to be the same angle as the shorter taper on an R8 collet) -- but the CAT-30 holders have a thicker flange with a groove in the edge to grip it by for the automated tool changer turret. This flange will *not* fit in your quick-change holder. And your quick-change holder *requires* the thinner flange to work.

And the CAT-30 does not have the cylindrical threaded collar which your NMTB 30 holders do which aligns the holder at the top. Instead, the CAT-30 ends at the end of the taper -- which is threaded, and into which is screwed (and Loctited) a stud with a ball end. This ball end fits into a gripper which locks as it pulls the holder up into the spindle -- the equivalent of a drawbar without having to run a thread in and out.

Also -- the two notches in the CAT-30 holder's flange are of different widths, to assure that the tool change turret always puts it in at the same orientation -- something which would be important with some rigid tapping (if the thread always had to start at the same orientation) but which probably does not matter for most other tools.

You don't have the tool changer turret (neither do I), and you can't use the CAT-30 in that spindle (perhaps you could turn the flange down to just the right thickness, and make a new cylindrical section which screws in where the pull stud was originally.

Now -- I have taken CAT-40 tool holders and replaced the stud section with a new cylindrical section to use in my Nichols horizontal spindle mill -- but that *does* use a drawbar, and does not care whether the flange is even there. The arbors for horizontal milling don't even have the flange. They just have a hole which is drilled through and a pin is fitted to engage the Allen head cap screws in the face of the spindle. (Those same screws fit into the slots in NMTB 40 or in CAT-40 holders.)

There are also step-down adaptors to accept 30-taper tooling in

40-taper -- so I use some of the holders for the Bridgeport on the Nichols when it makes sense.

I hope that this helps.

Enjoy, DoN.

Reply to
DoN. Nichols

I stuck in an awl from the bottom, I think that it is all the way through spindle. I will look at it from the top of the spindle when I put kids to bed.

It is a "Series 2 Interact 2" mill. This is a full CNC machine, no handles, it is fully designed as a real CNC machine. It does not look like a regular manual Bridgeport with servos attached. It was designed as a CNC machine from the get go and made in England.

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good question.

Reply to
Ignoramus6705

So I can buy any NMTB 30 foobar holder and it will fit? Nice!

Finally a straight answer. Thanks

It does, thanks a lot. I will buy one NMTB 30 toolholder to double check.

i
Reply to
Ignoramus6705

DoN, I owned that exact machine for a short while. I added a drawbar to it. Kind of strange cause there wasn't room for the typical six sided bolt head on the drawbar so it used three pin holes in the drawbar head and three pins on the power unit.

I didn't like this machine quite as well as the excello with a larger table, servos instead of steppers and taper 40 tooling, so I sold it. But it was a fine machine.

Karl

Reply to
Karl Townsend
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Hmm ... get a laser pointer and shine it up the center of the bottom? :-) (I didn't have one back when I first got the lathe and checked this.) BTW -- there was accumulated grunge in the spindle, but not a full blockage. I think that it was shavings from the plastic which was being milled on it by the previous owner, mixed with coolant.

As was my smaller one -- except that it was not made in England.

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Enjoy, DoN.

Reply to
DoN. Nichols

Which? My Series-I or his Series-II?

Interesting.

Sometimes we have to live with what we have -- especially with a fixed retirement income -- and no income from hobby machining. :-)

Enjoy, DoN.

Reply to
DoN. Nichols
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Yes!

Because I have fought through this same thing -- but having the Nichols with the less fussy 40-taper I was able to buy Cat-40 holders and experiment with them to see what I needed to do to make them useful to me. And verify that the conversion process for a 30 NMTB for the quick-change holder was not at all reasonable.

BTW -- I keep having problems remembering whether it should be NTMB or NMTB. If I had a new one in the original box, I could look to check. :-)

Good idea -- because there were several different quick-change holders which Bridgeport would supply -- depending on what the original purchaser wanted. Yours *should* be NMTB -- as the most common flavor, but it *could* be something else. (Not likely to be CAT-30, without a tool changer on the machine.)

Good Luck, DoN.

Reply to
DoN. Nichols

Your series 1

Reply to
Karl Townsend

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