The Home Machinist!

Instead of sitting back and sniping, I thought I'd share pictures of an accessory that came with the mill I am caretaking. As can be seen it is used to convert the horizontal mill to a vertical mill. The head is a 2:1 ratio over the spindle rpms, and it is reversable with a shot pin lever. Unfortunately the head height is only about 2-3/4" with the mill cutter in the vertical position. However if the cutter is in the horizontal position it is 8" from the table max.


The neat thing is that it is possible to rotate it in 2 axes so a slot can be cut at any angle.(?)


Here are the collets and other spindles. One of them is a morse taper #3 and I don't know if it is original to the machine.


One of the spindles has buttress threads and a key inside.


Here is the nameplate and I have not been able to find out anything about the mill.


Ordinarily it is fitted out with a #40 NMTB tool holder and a vise mounted on a heavy duty angle plate. Odd, and hard to see but it works better than this lashup.

Any one else have one of these?
--earlgo

Interesting. Can you find a name or # on that head?

That is an interesting head. I have a vertical head for my Nichols, but it only rotates, no nod like yours. Does the chuck holding the endmill come out? If you could use endmill holders with a less overhand, you would gain a little more height under the spindle.

I have not seen a tapered thread on a collet chuck like that before. Nice little mill,

Wayne

There is no marking on the head that I have found except for a serial number on the boss that is gripped by the outboard support.

The chuck is part of the spindle that is similar to the one with the buttress threads. The spindle has sleeve bearings and is held in place by a nut threaded on the upper end. If the nut is not locked securely then it will loosen and the spindle will walk out with easily imagined results.

Here is a pic with the cutter vertical and showing the headspace.


--earlgo

I seen a Cincinnati mill with this option, but I think it had a 50 taper. The idea as I understand it is used on a mill with out a universal table. The cutter could be turned to the proper angle for spiral milling with an index head for making gears and other things. The one I saw came off a liberty ship if my memory serves me right. They were scraping ships in Portland back in the late 60'S and early 70'S and the mill was supposed to have come off one of the ships.

Richard W.

That bushing # could hold the answer as to who made the head. I read some time ago that there were many manuf of optional heads and they would make the bushing for the specific machine. One of the deals was that the head was sold as being part of the larger machine and had no embellishment as to being other than that supplied. This all went out the window with Bridgeports and others as the individual vertical motors weighed less. Gripping the overarm and swinging the entire head out of the way became more practical. That head at the time was the best by having the "nod" function.

To which bushing are you referring?

This machine was inherited from my dad who bought it from a local college. The machine was in the college physics "laboratory" when I was there in the early '60s, and had a GE DC motor in it and the controller/rheostat was in another room, as it was mounted on a 3' x 5' board. My dad changed the controls to a SCR and small variac, but not being an EE, I couldn't make it run so I just took out the DC drive and put in a 2HP 220v motor and use the stepped pulley drive. My dad also disconnected the table drive shaft and put in an indepedant reversable single speed motor drive for the x axis. Not perfect, but it beats changing belts. Maybe someday I will restore the original drive, as I have the drive shaft and the internal drive pulleys are still in place.
Someday when I retire...

--earlgo

Interesting and useful device

I thought for a moment it was a Porter-Cable attachment:
http://www.lathes.co.uk/portercableattachment/

But, on closer inspection yours seems to be different .

If it fits the original overhead arm then it is likely to have been supplied by the mill's manufacturer (most of the add on adapters seem to have universal fittings).

_________________
Bill

So the spindle is removable - how is it driven? I expect there is a bushing on the lower end of the spindle and a drive gear on the upper end which is keyed to the spindle? The two collet holders you show appear to have different outside dimensions - are they for this vertical head?

If removable, I would make a new spindle, with maybe an R8 taper on the inside. It would be hollow for a drawbar to tighten the R8 or some other pull type collets. The end of the collet would barely extend past the housing, and it looks like you could get almost 6 inches collet to table.

Any chance the knee can be modified to lower a bit more? Might gain another inch...

Wayne

Leaves me with a question. It appears that the thread is machined in the wrong direction. Load, in a Buttress, is intended to be on the right angle face. Doesn't appear to be so in this picture. Am I missing something?

Harold

_________________
Wise people talk because they have something to say. Fools talk because they have to say something.

Your eyes are not deceiving you, the buttress threads are indeed sloping the "other" way. My guess is that when the nut is tightened, the sloped threads allow the collet to grip the tool. Odd arrangement to say the least.

There is a shank to fit the #40NMTB spindle and the shank has a gear attached to it that drives the internal gearing at a 2:1 ratio. I am assuming the internal gearing is a triplet of bevel gears considering that the spindle direction is reversable with a lever on the body. The spindle is keyed much like R8 collets and it can be taken out and replaced with the odd buttress threaded one.
As to messing with this, IMHO it just a curiosity to drag out every now and again, until I really need it. It is heavy and a bit awkward to mount so I will just make do with end mills in the #40 tool holders and the horizontal mill cutters.
As mentioned above there is a 4" mill vise mounted on the dumb side of an angle iron that is 3/4" thick x 8 x 8. I squared up the angle and ground the dumb side flat and perpendicular to the base. It was ground because the dumb side couldn't be reached with any other tooling available.

Thanks for the Porter Cable cut sheet. It is indeed very similar to this one.

--earlgo

Lot of things here. I agree the counter buttressed thread was probably to increase grip on an end mill or something. The reason I mentioned a collar is because there is often a slight difference between the overarm and the driving arbor, between centers, so an adj of the split collar bushing aligns that.
I see yours doesn't even touch the overarm so that means the head has an intregral stub at the fore end, clamped, as shown, by it replacing the overarm arbor support bushing.
Intially I couldn't believe that. I have an Index 60 which is also #40 stndard taper which also had an option of a verticle head. This has a V-ram arm. I wondered what the origional option looked like. It may have been yours.