Boring the MT2 on spindle

I've made a couple of items with female morse tapers. I've first bored the taper in the normal way very close to actual finished size then used a good quality (Dormer) morse taper reamer to to finish. If the reamer is sharp, and new ones should be, you only need the lightest pressure to get a nice finish. Use it to take off microscopically high machining high spots rather that actually doing all the work. Even by hand, going "off centre" is pretty much non existent in these circumstances.

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No argument with that, Jason

... I had the same thought; but was waiting for Sean to show us the drawing before discussing further.

MichaelG.

I would think it better if Sean kept everything in one thread as he has 2-3 threads concerning the spindle /vertical head  for his Centec .

It would certainly avoid confusion. Come on Sean do a quick sketch doesnt have to be anything fancy, as i am interested in how your doing it .

Edited By mark smith 20 on 17/11/2017 16:26:09

I was thinking about this this afternoon , the male taper would hold fast for the remainder of the turning . .. yes ?

Sean

Not really sure how the MT reamer can wander if it's following a pre-determined path by the roughed out shape? Surely it will cut relative to bored/tapered hole that's already there?

Besides which, your tail stock has got to be near enough bang on in the first place, otherwise you'd notice all those off centre holes you've been drilling. 

Michael W

Edited By Michael-w on 17/11/2017 21:24:40

I will keep everything spindle related to this thread from now on .... Feel like I'm being watched now ..... Just remember I'm a newbie to this and some of the terminology has me stumped , please try and keep things simple 😁

Sean

Edited By sean logie on 17/11/2017 21:16:43

Edited By sean logie on 17/11/2017 21:17:16

Food for thought John ....

I have ER32 collets along with mt2 collets . A ER32 on a spindle makes sense and would be so much more compact compared to using a ER32 on a mt2 taper . Maybe a change of plan 😋.

Sean

Edited By sean logie on 17/11/2017 22:21:18

you'd notice all those off centre holes you've been drilling.

Not necessarily. An off centre drill might just drill a bigger hole.  Think here that boring bars don't bore off centre holes.

Edited By not done it yet on 17/11/2017 23:12:12

Not being watched Sean just interested, im a relative beginner myself to anything id call precision machining.

I tend to jump right in with some difficult (to me at least project) and sometimes surprise my self and other times make a right balls up of it.

Edited By sean logie on 18/11/2017 06:02:04

Having just paid £35 for a decent mt2 reamer I now see a better solution to rejuvenating my knackered 50 year old tailstock taper - bore it out to 1" and heat shrink in one of the mt2 sleeves mentioned above. Thanks

I think it's far more common than you tend to realize, you can only cut it once and then it's gone. So you don't want to mess up.

I always keep in mind the expression of the late Joe Martin, CEO of Sherline;

"I never knew anybody who messed something up by taking too light a cut"

​​Now we can all just go listen to some nice jazz and spend the rest of the day chilling out about it. 

Michael W

Edited By Michael-w on 18/11/2017 13:07:34

What type of steel do you guys suggest for the spindle .

And ... should I go mt2 taper or er32 for the spindle .

Sean

If you make it MT2, I suspect that you will soon be asking us "should I get an ER25 or ER32 collet chuck for my milling spindle?". So why not just go ER32 straight off? Apart from anything else...

1. You will save about 50mm of headroom under the mill head that otherwise would be taken up by the projecting part of the collet chuck.
2. ER32 collets can cover the full size range so you can also hold drills with the same benefit of more headroom (especially true compared with fitting a drill chuck).
3. The cutter will be more rigid with less overhang.
4. You won't have to knock the end of the drawbar to release the MT2 taper when it gets stuck!

For a milling spindle, unless you have loads of MT2 tooling from the lathe that you want to also use in the mill, there seems to me to be no benefit in MT2 and loads of disadvantages.

But then again you won't be able to use any other type of MT tooling such as Boring head, Flycutter, saw & cutter arbors, etc unless you have then on less rigid parallel shanks that will have to go into the ER collet and therefore stick out more and could risk run out problems by the time you add up TIR of ER spindle, collet and tool.

Also you WILL have to bore the ER taper correctly as you can't get reamers for that!

Edited By JasonB on 19/11/2017 15:14:40

Dam...... I shouldn't have asked that bloody question ...

Which steel to use ? 

Sean 

Edited By sean logie on 19/11/2017 15:37:35

Still curious how you intend powering the spindle /head??

I have no clear ideas as of yet ,I may try and use the nose of the horizontal spindle .

Like this

https://www.youtube.com/watch?v=_dpovCSdKHY

is there any reason why you cant use an actual er32 spindle as a spindle . I was toying with the idea for something i was gonna make , as they are available with a straight shank up to 40mm , and up to 150-200mm long . The 40mm just happens to sort of fit the common taper roller bearings used in many mini mills etc... ie.. 62mm outside and 40mm id.

I did buy one from apt for around £20-25 and the quality is good ,though they have a flat on one side unfortunately.

**LINK**

Just another of my daft ideas.