# emco maximat super 11 spindle taper



## quickcut (Jan 29, 2017)

I have a maximat which I am busy setting up. The instruction book that came with the machine states MT4 in the spindle. Mine is the machine with the large bore(35mm). I found another machine listed and the specs stated the spindle taper is MT5. The bore is not deep enough to totally fit this taper. Is there a "short " MT5 collet ?  I have a collet chuck for c5 collets. It looks like the taper is correct (MT5).  The reason for all this is because the machine is turning a taper even though it is level and the spindle bearings are adjusted correctly and I would really like to buy one of those precision "shafts"  and see where it leads. thanks


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## mikey (Jan 29, 2017)

I'm not clear what you're asking. The large bore 35mm spindle has an MT5 taper. There are MT5 to 5C adapters; mine is a Royal. If you are thinking of installing your 5C chuck into your MT5 spindle then you need an adapter like this. 

On the other hand, zeroing a precision rod in a 4 jaw chuck will probably be more accurate if that is what you're getting at.


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## quickcut (Jan 30, 2017)

Hi Mike thanks for the reply, My question is really if there is a "standard "short MT5  that will fit in the head stock  as I would like to use a Morse taper test bar, I also have the original MT5 to 5c collet chuck but was really looking to use The morse taper test bar that I have . The reason for this whole escapade is that I am trying to solve the taper turning issue. When I purchased the machine it had two small  pieces of shimstock under the front part (under the chuck) of the head.  The manual shows shimstock packing of different thicknesses which appear to be only used on the rear side ( as apposed to the v way which goes right through the head).  Total confusion I am afraid.


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## mikey (Jan 30, 2017)

What is the MT on the test bar? You're looking for a MT reducer, right? You should be able to find a MT5 to whatever other MT you have. 

I have a Maximat Super 11 CD and the lathe has two leveling bolts at each end of the lathe and a lock down bolt between each pair. Leveling is a simple matter of adjusting each bolt one way or the other and then locking it down. The cabinet also has four leveling feet. Altogether, leveling the lathe is simple and (usually) fast. 

The manual I have for the Super 11 (the green one, not the red one like mine) also shows the same arrangement for leveling the lathe - 2 bolts at each end of the lathe. My manuals don't show any packing for leveling - weird. I assume you do have a Super 11; the later models did have an option for a large bore 35mm spindle that also came with a D1-4 camlock and an internal MT5 bore. If so, then it should have the leveling bolts as mentioned and I'm confused as to why yours doesn't.


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## quickcut (Jan 31, 2017)

Apologies if my description is ambiguous , My machine is level (as close as I can get it) and the adjustments you describe are there. The packing I was referring to is for under the headstock where it bolts on to the bed. My manual shows packings of various thicknesses ,but the exploded view shows them on one side only viz parallel to the bed. As I am struggling with this taper turning my question firstly is have I interpreted the manual correctly? (only a single packing on one side) and would this affect the head alignment. The question about the spindle bore /MT fitting ,yes, is for the use of a test bar. My machine has a 35mm bore, and is set up for a MT5 collet chuck. I have the collet chuck,  the taper is correct ,but the chuck is much shorter than a standard length MT5 . The bore of 35mm does not allow a MT 5 whose" thin" end is approx 37mm. Perhaps a solution would be to take a MT5 to MT4(or3) reducing sleeve and cut it to the same length as the collet chuck. This would enable me to use the test bar, but it really seems a strange solution.


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## mikey (Feb 1, 2017)

Okay, re the packing, you're referring to part 16 in various thicknesses. I'm not sure why there is packing only on the back side but I'm guessing the factory used it to offset the weight of the head stock that projects behind the ways. Regardless, you should still be able to level the lathe adequately with the bolts under the head stock and I don't think that shim will influence that. Well, it doesn't influence my lathe anyway.

Please pardon me, quickcut, but I'm totally confused about the MT5 taper thing. You're saying you have a 35mm spindle bore with a MT5 taper. This implies you have a D1-4 spindle mount, yes? The MT5 does require "short" MT5 tooling; a normal length MT5 taper will not go in all the way. My MT5 dead center has a total length of 2.05"/52mm from the small end to the large end where it goes into the 60 degree taper. The small end measures 1.668"/42.37mm, and the large end measures 1.753/44.5mm.

So, your 5c collet chuck has an MT5 taper on the back but it won't go all the way in, right? But here you say that the chuck is much shorter???
_I have the collet chuck, the taper is correct ,but the chuck is much shorter than a standard length MT5 . The bore of 35mm does not allow a MT 5 whose" thin" end is approx 37mm.
_
It sounds to me like the MT5 taper on your chuck is too long, or at least too long for the existing taper. Again, note that the proper dead center for this lathe is only a bit over 2" long and if your MT5 taper is longer than that then it won't fit.

Anyway, why not just get the precision rod and indicate it in the 4 jaw chuck? If you indicate near the chuck and another point farther down the rod then it will be accurate enough to assess the head stock alignment with. Or you can just chuck up a 6" length of mild steel and take skim cuts about 0.002" deep and check the OD at both ends and in the center;  that will tell you how well the head stock is aligned with the ways. If you are more concerned with leveling then a 2 collar test with a longer rod is probably more helpful.

Personally, I would trust a 4 jaw chuck that I indicated the rod to zero in before I would trust any collet, 5c or otherwise. 
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## Alan-bc (Oct 1, 2017)

mikey said:


> My MT5 dead center has a total length of 2.05"/52mm from the small end to the large end where it goes into the 60 degree taper. The small end measures 1.668"/42.37mm, and the large end measures 1.753/44.5mm.



A quick question here, and please don't be offended by my asking .. are you pretty sure about your measurements?

Here's the story. 

I've made the commitment to ER collets for darn near every other machine in the shop, and decided to use them for my Super11 as well. 

To that end, I bought an MT5 to ER32 adaptor.

Of course, it's a full length MT5, and so will have to be shortened.  My plan is to mount the adaptor between centers on the lathe and attach an air cutoff tool to the table, gently feeding the cutting wheel in as the adaptor turns.

So, where to cut?

Now, my standard work methodology is "measure once, cut twice, get out the welder". 

But I'd just as soon _not_ make a mistake with this project.  I don't want to cut it too long, because shortening a wee bit using the scheme above could be troublesome.  And I don't want to cut it too short because I'd like as much material as I can in the two tapers.

So I've made what measurements I can of my spindle (tricky) and am now trying to double-check those measurements.

Thanks for any thoughts.

Alan


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## petertha (Oct 1, 2017)

Not sure if this helps with what you are asking about, but I bought a reasonably priced ebay precision ground MT3 test bar. Using a MT3 > MT5 conversion socket I was able to verify my lathe headstock alignment. And the bar serves double duty for tailstock alignment which is MT3 socket.

post #23
http://www.hobby-machinist.com/threads/tail-stock-alignment.53621/#post-453559


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## mikey (Oct 2, 2017)

Yeah, I recall measuring pretty carefully before responding to quickcut. However, you have to remember that I was measuring a dead center, not the spindle taper. I will say this; when I use the dead center, it takes a pretty solid hit with an aluminum bar to break it loose so the fit is pretty good. 

What I would do is measure the end of your spindle taper with a telescoping gauge and cut it just a little long, then trim to fit. I assume by "between centers" you mean that you will center drill an accurate ground rod on both ends and then mount it in a collet and lock that in the chuck, then mount the rod between centers and trim the end of the MT5 taper, right? If so, then cut it a tad long and check the fit. You should be able re-mount the chuck accurately enough on the rod to trim it more if needed.

I dunno'. What do you think?


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