Author Topic: Securing Morse taper end mills in the spindle?  (Read 3548 times)

Offline Eugene

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Securing Morse taper end mills in the spindle?
« on: March 16, 2016, 02:37:53 PM »
I feel very silly asking this, but how do you secure a number one Morse taper end mill in the lathe spindle?

I've only just started to use the milling slide, with mixed success thus far, but one problem is the milling cutters rattling free under load and vibration. One of them has a threaded hole in the back end so a tension bar through the bore holds it nicely but the others just have a plain tang. I'd be quite happy to drill and tap them but how does one hold the things to do so? Or is there some other wheeze?

Eug

Online awemawson

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Re: Securing Morse taper end mills in the spindle?
« Reply #1 on: March 16, 2016, 02:48:26 PM »
Eugene,

Throw away any without draw bar threads - they are a liability. I learnt this to my cost decades ago with my first Mill / Drill - One came loose and scarred the table for life  :bugeye:

Andrew Mawson
East Sussex

Online chipenter

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Re: Securing Morse taper end mills in the spindle?
« Reply #2 on: March 16, 2016, 02:52:56 PM »
Personaly I would go for a ER16 collet chuck and a set of ten collets 1 to 10mm from China , I am very pleased with mine worth the wait .
Jeff

Offline sparky961

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Re: Securing Morse taper end mills in the spindle?
« Reply #3 on: March 16, 2016, 04:46:59 PM »
They actually make/made milling cutters without drawbar threads? Drills and reamers I get (when used correctly the cutting forces tighten the taper more), but not something like an end or face mill. That's just scary.

Offline Pete W.

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Re: Securing Morse taper end mills in the spindle?
« Reply #4 on: March 16, 2016, 04:56:20 PM »
Hi there, Eug,

If you have a copy of 'Simple Workshop Devices' by 'Tubal Cain' (the real one - aka Tom Walshaw) or can get access to a copy, have a look at page 106 onwards.  This book is well worth having.

He described how to make holders for 'throw-away' endmills by modifying a Morse Taper drill-chuck arbor.  He first mounts the arbor in the female taper of his lathe mandrel and machines a short parallel section in the Jacobs taper part.  Then he reverses the arbor and holds it by that parallel section with the narrow end supported with the tail-stock centre.  In this configuration, he turns a short parallel section in the narrow end of the taper, just long enough for the jaws of his fixed steady.  He next withdraws the tail-stock, mounts the fixed steady and turns off the tang, faces the end and drills and taps for a draw-bar.

You could, perhaps, adapt this procedure to your tanged end-mills.  That will depend upon the relevant parts being soft enough to be machinable.  You might be able to omit the stage of turning the parallel section at the thick end of the taper if you can grip the business end of the mill, with soft packing pieces, in a collet or in a four-jaw chuck.  There should be a centre drilling in the tang of the end-mill.  And you need a fixed steady.

Tubal Cain's other book, 'Model Engineers Handbook', is worth having, too.

I thought Tubal Cain also listed the draw-bar thread sizes for various Morse tapers but that, I found, is in G.H.Thomas' book, 'The Model Engineers Workshop Manual', on page 159.  This book, too, is worth having.  (Please don't lecture me about omitted apostrophes - both the authors omit them!)  He specifies " BSW for MT1.     
Best regards,

Pete W.

If you can keep your head when all about you are losing theirs, you haven't seen the latest design change-note!

Offline Eugene

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Re: Securing Morse taper end mills in the spindle?
« Reply #5 on: March 16, 2016, 05:17:55 PM »
Thanks Lads,

I'll try and think of something a bit less tedious than the Tubal Cain method; if I can't I'll bin the end mills and put it down in (in)experience. For the work I'm doing a parallel shank in the three jaw will probably be good enough until I contemplate the Chinese collets route.

Eug

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Re: Securing Morse taper end mills in the spindle?
« Reply #6 on: March 16, 2016, 05:34:09 PM »
You could bash your end mills into a sleeve and drill both , metric collet drawbars are 6mm and imperial are 1/4 Whit ,  http://www.arceurotrade.co.uk/Catalogue/Adaptors-Sleeves/Morse-Taper-Straight-Sockets---For-Tang-Type-Tooling .
Jeff

Offline Jonny

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Re: Securing Morse taper end mills in the spindle?
« Reply #7 on: March 16, 2016, 05:50:14 PM »
Ideally it needs a drawbar fixing in to back of MT collet or face the consequences your finding out.
That still wont help with MT1 presumably in to MT1 taper, better of junking those MT milling cutters best left to drills and reamers with a tang.

IF tapers MT2 it opens up possibilities but still needs a drawbar. Best form of that is the MT collets with parallel internal which hold anything better than any ER more akin to the reknowned R8 work holding.
Available from many places including Arc. http://www.arceurotrade.co.uk/Catalogue/Collets/Morse-Taper-Collets/MT1-Collets-Imperial-Sizes