DIY Milling/Drilling Spindle

I plan, at some stage, to make a milling/drilling spindle to use in a vertical slide on my Flexispeed. My thoughts are to fabricate a suitable housing, with bearings, for one of these spindles and then run it with a sewing machine motor.

**LINK**

Does this sound like a sensible plan? I like the idea of the spindle as it gives the collet holder rather than fabricating a spindle with a screw-on chuck or similar.

Regards,

James.

In my opinion sewing machine motor may be too low on power for much milling with your spindle. Might be fine for drilling small dia holes though. I would look for the biggest motor that fits without being in the way too much. You can belt it in several steps to a more remote location if need be. JD

James,

You should find several relevant discussions in previous threads.

... Have a look at Roderick Jenkins' Album for starters.

MichaelG.

Thank you for the comments and suggestions.

James.

James,

Unless I have misunderstood your intentions, aren't you about to duplicate effort? If you intend to add a milling spindle to a vertical slide, surely that is just adding another link in the chain, so to speak. Mounting a cutter in a collet holder in the lathe headstock and holding the workpiece on the vertical slide will achieve the same result. Or am I missing something blindingly obvious? If you want some idea of what the finished article could look like, have a look at this:

The motor is about 90W and for scale the collet is ER25. (The extra pulleys - unmachined in this picture - are to provide alternative spindle speeds.) The motor that I purchased (new) cost a little over £20 inc postage and included a primitive three-step speed controller. Allegedly revs to 10,000 rpm! Spindle is from CTC and runs in ball bearings. Only thing to watch out for is the direction of rotation of the motor.

John

John,

Thank you for the details of your spindle.

You are not missing anything: I want to be able to use a mill in the headstock chuck to mill work on a vertical slide and have a separate spindle to mill and drill work held in the chuck.

James.

John,

Out of interest: do you find that the motor is powerful enough for light milling?

Regards,

James.

These spindles are remarkable value for money and similar ones I have bought have been very well made. They are an ideal basis for making a milling spindle or simple indexer.

Doug

I can't see any spindles on the http://www.ctctools.biz/ site. Do you have a direct link please?

Roger

I wonder if the spindle uses a "collet chuck" from CTC like this:

**LINK**

as the shaft and chuck which is then mounted in bearings? These are remarkably cheap and well made and a great basis for tooling.

Mmmm... I've considered that path before, then I read the earlier posts and took them to imply that a complete mounted spindle was available. Oh well, ...

Roger

Roger/John,

My mistake for using the incorrect terminology (again!). I should have written collet chuck, not spindle. Sorry for sending you on a wild goose chase. I should have explained that the spindle as a whole was home made.

James,

To be perfectly honest, I haven't used the spindle for milling, just for a few drilling operations, I use my mill for, well, milling. I imagine that it would be perfectly adequate for use with small diameter milling cutters or engraving, for example. It's never going to be able to rip great chunks out of stainless steel, though.

John

" I should have explained that the spindle as a whole was home made."

In which case, 'Well Done', it looks to be a very neat job!

Roger

There was an article in MEW some time back by Dick Stephen on making a new high speed head for an X3 mill based around IIRC an ER25 collet chuck of this pattern. Neil can probably advise which issue?

Here is my cobbled together version of a tool-post spindle. It was driven for years by a flexible shaft from a remotely fixed 1/4hp motor (now driving my tool-grinding spindle) It can be used either way up and is always at centre height when mounted. It now has a 90 watt sewing machine motor (with basic speed controller) which is fine for drill spotting prior to transfer of the work to the drilling machine or perhaps engraving, but is not enough for milling, aside from the wrong type of taper mount chuck, it struggles with anything over 1/8 inch. Spindle speed is about 2000 rev based on the stated motor speed of 6000 revs.

I think Roderic Jenkin's suggested in another post that a 120 watt motor was the minimum.

It has also been mentioned to watch the direction of rotation. This motor was rotating in the wrong direction for my application, when received. It was a tricky/delicate, but not impossible job, to identify and swap the field coil connections inside the motor.

With regards to the usefulness of ready made ER20 straight shank chucks, I used one (from ARC - no connection) for an indexing head for my home made tool grinder which saved a lot of work. I lapped the shank and bore of the indexing head for a close running fit. Dry lubricated with graphite and it spins very freely without shake.

Phil

Edited By CotswoldsPhil on 02/01/2016 11:10:20

Phil, I'm curious to know how the vertical bush which is bored out (presumably) for the tool post stud, is attached to the spindle housing - is it welded please?

I have a 1/4 hp 1400 rpm parvalux which I use to power a potts milling attachment see photo.

It provides adequate power for end mills up 6mm used on familiar model engineering materials. The key for me is fine feeds, high speed and light depth of cut.

I have the potts mounted on the vertical slide and the power from the parvalux is via an overhead drive.

The potts is really robust design. I was lucky to acquire an old set of castings about two years ago. They were supplied to the original buyer by woking precision models in 1974 so it was best part of 40 years before I got them and made the attachment. As far as I know the castings are no longer available but if you are ever offered a set, buy them. Apart from usefulness of the attachment it's quite a challenge to make one.

hny to all geoff

I'm sure Hemingway used to offer them and presumably have the patterns since they took over the Woking stuff. I think they stopped offering the Potts milling spindle when they introduced the Quick-Step; which is a pity since I don't really think they are rivals.

Rod

Hello John.

I clamped the vertical block to the tool-post (as when in use) and scalloped out the seating for the spindle housing with a boring bar. It's all held together with 2 cap-head bolts (loctited) one each side of the tool-post hole. It's been like that for nearly 40 years and never moved.

The Potts is really robust design...

I agree.

I acquired a Potts milling attachment when a Super 7 came into my ownership about a year ago.

I remade the spindle to suit ER20 collets and managed to hang a 1/4hp small frame motor out the back or at the top as required. It has 3 speeds <>700, 1500 and 2840.

Phil

One day I'll get a post done first time!

Edited By CotswoldsPhil on 02/01/2016 15:59:51

Thank you for all of the ideas and comments. I have now ordered a couple of ER11 collet chucks on 4" parallel shanks to use as a base for a spindle and for a collet chuck for the headstock. I shall let you know how it goes, in due course.

I have not sortedout a motor yet, but there is plenty of time for that yet.

Regards,

James.

Edited By James Alford on 03/01/2016 09:36:27