Pm1440GT one piece spindle bore dead center

I do not question what PM says. But calling it a Morse taper leads me to think it has specific dimensions. If so I want them even if I don't need them.
If I had one to measure how would I know if it was a MT5 1/2 without having to rely on PM?
Or is it a proprietary taper used only by PM?
 
mksj said:
You have a spindle adapter that fits a standard dead center, that was the question, and that is the answer to this thread. I see no other question of fitting anything else. Almost every new lathe in this size comes with these types of adapters. If you want to fit something else like a 5C collet closure, that is different story, but that was not the question. The spec's on the PM lathes are spelled out in the site description and the manual, might be worth reading the manual if you do not believe that it is a MT 5 1/2, if you need the dimensions to make an adapter then measure it.
Click to expand...
Actually the question was:
Lonewolfgun said:
Does anyone know where to find a one piece MT5-1/2 that'll fit the spindle bore?
Click to expand...
As far as I know there is no listing of a "MT 5.5 taper" anywhere but on the PM site dealing with this particular lathe.
IF no-one else in history has ever had, heard of, or listed a piece of machinery with a "MT 5.5 taper" the probability is that it is some weird taper that has been recently devised, not a Morse taper and has just labelled a "MT 5.5 taper" by some advert writer.
The argument that "Almost every new lathe in this size comes with these types of adapters." is spurious. How many times has there been a post made by someone who has bought a, new to them, lathe and found the adaptor/sleeve missing and wanting to know if anyone knows where one may be purchased? Quite a few over the years.
At the end of the day the headstock taper in question is not a standard Morse taper. Short of a drawing and measurements from PM,(which may be coming),measurement is the only option.
I have a MT 6 taper in my headstock and this means I can buy centres, adaptor sleeves, collet holders, odd arbours etc off the shelf just about anywhere in the known world. Very handy having standards that the whole world agrees on.
It looks as if buying sleeves may be an issue. To this end I repeat that without measurement there is absolutely no way whatsoever to know what that taper is especially as it seems to be a non-standard unknown one that has been labelled a MT 5 1/2.
As I have previously stated grade 9 bolts are now apparently a,[propriety],thing and it seems that a new class is being put aside for them.
If the is such a thing as an international standard MT 5 1/2 taper please supply the documentation or links to such as I would love to know and would like to stick the specs in my library for reference plus it is Sunday and I always like to learn new things on Sunday.
 
I think that there is a market among PM customers for longer blanks that fit in these spindle noses. Both the OP and myself have expressed an interest in a one piece dead center that fits in the taper. Again, not that there is anything wrong with using a smaller dead center in the reducing sleeve.

Alternatively, one could buy a spare adapter sleeve from PM, and then weld or braze in a similar material. For example, bore the sleeve’s internal taper to be straight, press in a custom “tip” which is a shaft machined on to round bar stock, braze or weld, and then cut the tip just like you want it. That would be a one piece dead center!

Obviously if you chose to braze it, you would not press in the stub shaft.
 
The question marks in the title of this eBay auction indicate that the Seller is unaware of the exact specifications for the outside taper of the sleeve. More info in next post.

EBE02A5C-0C51-4CA2-B8F6-6958ACE8C437.png
 
This is a screenshot from the item description for the adapter sleeve pictured above:

62778D04-B4C0-42A4-889F-4214AE5C83C3.png


Hmmm...”L and D1 spindled lathes”. No mention of Morse taper. This makes me wonder what the exact specifications are for the internal taper of a D1 (as in “D1-5 or D1-6 camlock”) spindle nose.

Maybe a D1-5 has an MT5, and a D1-6 has an MT6?
 
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At the risk of getting away from the original question, this company appears to sell “off the shelf” Morse taper reduction sleeves for spindles:

www.bison-bial.com

IMTS 2024 - Bison

www.bison-bial.com www.bison-bial.com

See also:

Morse Taper Sleeves

Pass-through reduction sleeve are for morse taper with thread. Some sleeves have flattening for easier remove from holder.
toolsmach.com toolsmach.com
 
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mksj said:
It really doesn't matter what the internal taper of the spindle is, all these lathes come with an adapter for a spindle adapter for the spindle to use a dead center, on the 1440GT per above it is a MT3, on the TL series it is a MT4. They also should have come with dead centers in the tool box. If you read the manual and the description they describe this. No need for fairy dust to determine the sizes.

The 1440GT Manual States:
Spindle:
Chuck/faceplate attachment D1-5 Camlock
Internal taper MT5-1/2

TL manual states that the spindle is a MT6 and the site description states:
Spindle:
  • Spindle Mount D1-6 Camlock Quick Change
  • Internal taper of Spindle is a MT 6 (With included reducing sleeve) MT 4
  • Spindle bore 2.55” in. diameter (will pass a 2.500″ piece)
Click to expand...
There is no such taper as a MT 5 1/2 listed anywhere , except with PM........
 
Here is a long, wandering video about a guy with a mystery taper:

 
And another video of a gentleman with a mystery taper:

 
Sorry to keep posting YouTube video links, but these 2 are so pertinent to this thread:


and

 
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