Can a Drill be a Mill?

It may seem a daft question, but looking at the cheap end of the market, the Mills do have a close similarity to the humble vertical drill!

I was looking at the stand alone two axis slides which could be incorporated for work holding

If a bracket was mounted of the drill column, an extra bearing could be used to support the spindle

The existing drill chuck could grip a stub shaft, which would run in the column bearing and a second chuck mounted in the end

The question is......Has anyone out there, tried it?

I would say the idea is definitely feasible and very interesting

Bob

Bob,

Yes it's 'possible' ... some of the more substantial British drills had XY tables available.

The big caveat is that you must use a proper milling chuck.

Frankly; I would rather use a mill for drilling than a drill for milling.

MichaelG.

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P.S. ... I do realise that you are thinking about an outrigger bearing [which seems a good idea]; but my conclusion stands.

Edited By Michael Gilligan on 13/09/2016 12:46:37

Thank you Mike

I`ve just had a look at my drill, which is now 25 years old and with a drill in the chuck, there`s no sign of play in the bearings

An outrigger bearing can easily be fitted

What`s special about a Milling chuck, please?

Bob

I dont think it's daft at all, Bob.

If you look at the clarke major mill or older tiawanese Ajax milling machine, this is basically an inspired step up from a pillar drill,

They kept the round column, and fitted a dovetailed compound table and fitted a rack and pinion movement to the head.

Later on, as we can see there are many more mills around now which are built from the ground up with dovetailed head too.

You just have to be careful with the quilll, not to use it extended and setting the depth would be rather iritating after a while. I would consider getting a proper one, would be my advice though, it would be a whole lot of trouble to get it to a user friendly state.

Michael W

I believe that the general gist is that a 3 jaw chuck doesn't work very well with radial / sideways forces.

I am not expert but I guess as the chuck rotates under sideways pressure there will be moments where one jaw is taking the full load of the milling. Collets on the other hand have continous contact all the way around the tool.

Courtesy of Google here are a few approaches

Popular Science Jan 52, Popular Mechanics July 54 & Jan 69

If you could get your hands on the sort of rather heavy pillar drills some tool rooms used that might be ok. I'm pretty sure that the cheaper lighter far eastern ones would vibrate like nobodies business. I've tried it.

A smaller sized far eastern miller I bought of some one who reckoned it was no good had been trying to mill with the drill chuck that came with it. I also initially tried it on the combined mill lathe and it didn't work out. They just loosen.

Milling chucks are usually used with a draw bar - not normally available on drills. I can't recollect seeing any with tangs.

I have used a cheap x-y table on the drill for "jig boring", drill followed by reamer. Slides on the the one I have are a bit naff and rough and the distance scales useless so I measured various spaces with a digital calliper to set the hole spacing.

John

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Thinking the same way, I did some experimental milling with a pillar drill and got very poor results.

The main reason, I think, is that my admittedly weedy pillar drill wasn't designed or built to resist sideways forces. If I'd gone to the trouble of replacing bearings etc, then I'm sure something else on the drill would have needed stiffening up. I concluded it was impractical to do an effective conversion with my limited skills, time and tools.

I learned from the experiment but decided not to throw good money after bad. I rarely use my pillar drill now that I have a milling machine.

I'm very much a beginner and will be interested to read if anyone did it successfully.

Dave

The sort of drill I mentioned that might do it could well be a gear head and weigh rather a lot. They were much heavier than modern machines I have noticed of the same type, Bigger too. I really have no idea what in betweens might do.

John

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The important difference between a drill and a vertical milling machine is the drawbar that is fitted to the milling machine. Without a drawbar the cyclic loading on a morse taper will cause it to loosen and fall out with the forseable consequence of damaged workpiece. If your drill does not have a morse taper it probably still has a Jacob's or B type taper into the chuck.

Martin

I tried milling in a drill press years ago before I bought a mill and the main issue was the column, column joint to base, and the head to column joint were not rigid enough. Even with light cuts everything was vibrating and deflecting and results were awful quality of work. Most drill presses simply are not made rigid enough for milling. They are designed for drilling forces only. If you happen to find a very heavily built toolroom high precision drill press it may be ok but garden variety light/medium duty ones are not.

The chuck is the second issue, as others have mentioned they are not intended for milling, although you may get away with light cuts. JD

Many thanks chaps for your feed back

It was just an idea

Had I gone down this route, I would probably have used flycutters anyway

Bob

Fobco made a version of their drill suitable for milling. They overcame the tool holding issue by having a nose thread on the end of the spindle so that it would take the Myford style patent collets. They also added a worm and wheel to control the down feed. Their drills already had a quill lock, which most don't. Fobco drills are certainly substantial and I guess that with this modifications that were at least as good as the budget mills available to model engineers although they still had the problem of losing location when the head was slid up and down the column.

Rod

Bob, Flycutting would only compound the problem of using a drill chuck as the heavy interrupted cut would shake it loose in next to no time.

Bob,

I have sent you a PM [Personal Message]

... There should be a 'notification' at upper-right, just by your avatar.

MichaelG.

I could be wrong here but, I think a drill press would struggle with the Radial loads that a milling machine encounters. The drill press would probably have bogstandard ball bearings which are not really designed for Radial loads more for Axial. I think a drill press's days would be numbered if used for anything but the very lightest milling.

cheers.

When I first got my Rexon mill I knew nothing of milling, I wasn't even into model engineering, but was wood turning, and required a drill press. Some time later, when I got an engineering lathe, I started to make tools, and bits and pieces for wood turners. I then made some tap wrenches, the first of these I decided that I would try milling a flat bit in the middle (I had got hold of a 1/4" end mill). So put the end mill in the Jacobs Chuck, and away we go machined one side, turn it over, and just about finished the other side, then thump, the 3 mt on the Jacobs Chuck fell out. I still use the tap wrench, but I got a proper collet chuck before any more milling. My thought was, milling machine, it is supplied with a chuck, that must be all I need. But a chuck with a draw bar, and suitable for holding the cutters. Also the Rexon has a threaded spindle nose, I have a fly cutter that fits on here.

Ian S C

Thank you, Ian

I started my milling experience at the age of 17 years at the beginning of my apprenticeship at a large engineering works

We just milled flats on blocks of steel all day long and was told by the foreman to change the cutter

Out came this giant spanner, about 2 1/2" AF'

Blimey......This nut's tight?

Got a tube on it......Still no joy

Out comes the lump hammer.........Clout! Bang! Heave!......More clouts!.....Bang Bang.....Thud!

At last it came undone!

Little did I know, it was a LH thread and had sheared off!

Needless to say, the air was blue for a time.......and that was my introduction to left hand threads!

Bob

We all live and (hopefully)learn.

Ian S C

HI Bob
Yes here is my drill with a X & Y table fitted