Drill-quill tailstock?

[Doc Nickel]

Wait a second, you want to build something that'll take time and effort when you can do it on the Omniturn?

-Er, yeah. The CNCs are intended to do the big jobs, the 200-plus-part jobs, if all goes well. Why take the time to setup, tool up and program- which for me takes entirely too long, still- when I can set it up in a smaller, secondary machine, while the CNC is is running a bread-and-butter job and kick it out in an hour or two?

I can see why he wants to add something though. It won't be a classic tail stock which can be used with great force. There ain't room for that sort of option. But a tail stock like tool post that stays registered to the spindle axis for guided drilling and tapping would be VERY nice.

-Bingo. It's a tool to make an already-useful machine even more useful. No, it won't be quick to make, but if done well, might easily be useful enough to make it well worth the time.

Aaaagggggrrrr, stop this nonsense. Do it in the Omniturn, that's why you have the Omniturn. If you need "feel" get one of those drill thingies shown in post number twenty-three (cheapo, offshore ones are around a hundred bucks)

-No, I have the Omni to manufacture more complex parts. Stuff that actually takes some work. In this case, I just need to drill some weeny holes, accurately. I already have a machine that perfectly capable of doing it, and I only needed to do a dozen or so.

The current job is done- as noted, I had a Hardinge short-throw slide with a toolpost and ER holder. It did the job, as it's done before, but also as before, I kind of wished I had more of a "drill press" style handle to make it a little quicker still.

I went ahead and ordered a tailstock body- $20 and shipping- off eBay, whose measurements I think will make it adaptable. As I have time, I'll see if i fab a new ram and come up with either a lever feed or better yet a spider-wheel feed.

It may prove to be a waste of time- more projects than I'd care to admit wind up that way - but if it works, I think it'll add a fair bit of functionality to the machine.

Doc.

[BCRider]

Spider-wheel feed? Wha'zzat?

[Oldguy]

BCRider - Take a look at this video by Stefan Gotteswinter, starting at 23:45:

https://www.youtube.com/watch?v=n1ytS1lhVFg

Glenn

[BCRider]

Perfect, thanks Oldguy. Seen that a couple of times but never heard it called a spider wheel..

Yes, that would be a nice mod. A nice alternative to a plain lever for peck drilling with the smaller sizes.

For a smaller second ops lathe I think I prefer the idea of a simple lever along the lines of the Taig. The reason being that on the little short Hardinge of Doc's there won't be a lot of reason or room for a long travel tail stock. So the limited travel of a lever style would not be a big hindrance. And with the lever style the entire short quill is easily changed for different uses. So that might be a lot handier than an actual tail stock too for handling a variety of chucks and centers. And the lever can be used for bigger stuff with more loaded torque or without a lever and free spinning for things like very small drills and taps where just hand gripping will supply the force needed easily with the safety of instantly slipping.

But I might also be misreading the size of his Hardinge too. The pictures suggest something pretty small. Bigger than a Taig or Shereline but still fairly light duty. Or am I being misled?

[reggie_obe]

This is a Hardinge HSL: http://www.lislesurplus.com/H/Hardin...ecision-lathe/

[Tom S]

That Hardinge is a stout little machine, completely different class than a Taig or Sherline. It's basically a DV-59 headstock modified for a rear mounted motor and with a shortened bed.

What Doc really needs for drilling small holes accurately with a high speed spindle is a Schaublin 102 with a star wheel tailstock. But I hear that they're only good for looking at, so it should be pretty easy to get one for a discounted price. 😉

[Doc Nickel]

Spider-wheel feed? Wha'zzat?

-Spider wheel, capstan wheel, spoked handle, drill-press handle, etc.

For a smaller second ops lathe I think I prefer the idea of a simple lever along the lines of the Taig.

-Well, really, as you say the throw will be so short I doubt I'll need a three or four-spoke spider, but the same rack machanism that drives it could also be actuated with a single lever.

The casting I bought has a nice beefy boss for the quill locking cotter. I might be able to just drop a custom-fitted pinion right into that hole, a ram with an appropriate rack cut into it (and only about 1-1/2" of throw, really) and just have a single lever on the pinion. A 3/4" OD pinion would give me a little over an inch of travel with a 180 degree turn.

But I might also be misreading the size of his Hardinge too.

-Nope, it's wee itty-bitty. Full-size DV-59 headstock (more or less, the DV is underdriven) but even that's not a huge lathe. Headstock is physically smaller than that of a Southbend 9".

But the bed is dinky. Only about a foot long. The thing's meant as a 'second operation" lathe, typically for things like facing the 'pip' off the pack of pieces that were parted from bar on a bigger machine. Usually you set it up so the operator of the big machine can do a "second operation" to the part, while the CNC is running the next one.

As such, one of the most common tools fitted to them is a fixed cross-slide. You just pop the piece into a collet, spin it up, crank the lever from stop-to-stop to face the part, shut it off, pop the part out, move on to the next one.

Which is primarily what I got it for, both for the big turret lathe and the CNCs.

But, it's such a useful little machine, I keep thinking of other stuff I can do with it. As I said, I got through the current job with tooling I had on hand, but it was a bit cobbled and a little fiddly. The thing doesn't need a proper tailstock, but having a "drilling tailstock" would, I think, be very handy indeed.

Doc.

[BCRider]

If the capstan were an easy lift out fit and you had a mount for the floating bar of a lever then you'd have options. The capstan with suitable gearing would be nice for longer travel and for additional force. The lever would be nice for more sensitive drilling. With all this in mind and to aid with the sensitivity if you don't use a Morse taper in the end of the arbor but instead go with swappable arbors the shaft size could be something small like 5/8 or 3/4. Or if there were two capstan drive options one could have a thru hole for a small size shaft for small jobs?

I'm adding features which of course adds time and complexity. But with a little thinking I feel like there's perhaps an option where you can start with one and build on it. For example start with a slightly oversize capstan driven quill. But make the quill easily removable. You might have a couple of quills with racks with an ER16 on one and a small nice quality drill chuck on the other? Or just go ER instead of chuck since it would handle most drills. Then perhaps the other rack equipped quill would be set up with a live center on it?

Then lift away the capstan and slide out the quill. Replace the quill with a liner that has precision bored and centered bushings in the ends for a smaller lighter duty shaft. And where the capstan came out a split cotter clamp fits in to secure this liner. The end of the liner out the back has ears for connecting an optional link for a lever handle. And the handle's length would decide if it's a very sensitive feed for very small drills or a longer one for slightly larger sizes that need marginally more push while still wanting to retain some feel. Something like one of these could also have a small thimble style tap wrench on the end for doing smaller threads. Sky's the limit on both. Just add rack drive quills as you need them for each purpose or the smaller direct or lever operated smaller sizes with the liner as needed. I'm thinking short travel for all this. Maybe a 3 inch housing on the tail stock for the rack drive with the rack driven quill being about 6 inch long? When fully back most of it would stick out the tail end of the short tail stock body that is also only 3 inches long so it doesn't take up much room on the already short bed? The liner would only be the 3 or 3 and a bit with the stop flange on one end and the lever link mount off that flange.

Howzzat for off the cuff designing?

... makes me want to go buy a small easily carried desk top lathe all of a sudden....

[The Metal Butcher]

There should be an easy way to repeatedly index the cross-slide to the same value. Robrenz and Stefan can do it, so can you. Then it's just a matter of keeping your toolpost square, which you should do anyway.

Cheap drill press quills are so sloppy you'd be going backwards in precision.

[JRouche]

DV-59 headstock (more or less, the DV is underdriven) but even that's not a huge lathe.

Doc.

I have always wanted one of those. Perfect size for us home shop folks.

So yeah, I am a lil jealous to be honest. Sure, none of the stuff you might need from a lathe
.
Its more than I could have hoped for basically. Just never came to being...

The Hardinge branch is more than I can or could afford. Put that name on anything and the idiots seem to think its gold.

What ever, It is ok stuff. Not golden folks... JR

P.S.> I only say this for the up and coming in our Hobby right? JR

[RB211]

I have always wanted one of those. Perfect size for us home shop folks.

So yeah, I am a lil jealous to be honest. Sure, none of the stuff you might need from a lathe
.
Its more than I could have hoped for basically. Just never came to being...

The Hardinge branch is more than I can or could afford. Put that name on anything and the idiots seem to think its gold.

What ever, It is ok stuff. Not golden folks... JR

P.S.> I only say this for the up and coming in our Hobby right? JR

Give it a few more years, the upcoming generations don't know Hardinge just like they don't care for Harley Davidson. There won't be any nostalgia emotions driving up the costs.

[Doc Nickel]

Actually, DV-59's can be had cheap and by the binload these days. I'm always seeing them, sometimes with tooling, sometimes stripped, for anywhere from $1K to$3K.

When I got this HSL, all it had was the fixed, single axis lever cross slide. I knew that I wanted the X/Z slides, in order to use it for proper turning, and good examples of those, at least on eBay, tend to go for $1,000 to $2,000.

And as I was looking for a good one (eventually had to settle for an older version in good shape, for $700) I kept running across entire DV-59s, that would have the X/Z slides, a collet set, a tailstock, some tool blocks and occasionally even the lever turret, for $1500.

Doc.