Modifying a Southbend Headstock for Indexing

[Bernd]

I've decided I need a break from engine building, so the Coke Bottle project will take a short hiatus as I pursue some tool building. I really need the change.

Now that I've got the Bridgeport I can do some serious milling. So what I need for the milling machine is a nice piece of indexing equipment. I've always thought of building one those that have been written up in the magazines for the Grizzly mini-mill but never got around to it. But now having a much larger mill I figured I needed an index. So keeping in with the spirit of Madmodder I need to modify something to fit.

Just so happened that my dad was going to toss out a lathe he had for longer than either of us could remember. It had been given to him by a friend when dad was looking for his first lathe. Problem was it was missing a tailstock, lead screw, bed support at the tailstock end and a few other things. Dad had in mind of restoring it to use for building steam engines. He scrapped the ways and the bottom of the head stock. Then for some reason it went under the bench and stayed there for quite a number of years. Just this past year he was cleaning house and wanted to through it in the dumpster. I took it home figuring I'd find something that could be done with the parts.

Enter "Mainer" on HMEM with his pic of what he did.  Link Here

This is the pic that got me all excited that Mainer posted. I figured I could do that.


Here's a pic of the Southbend headstock I've got all taken apart and ready for modification.


I'm going to make myself an indexing head for the Bridgeport.

It all needs a bit of cleaning and some lathe work. Don't quite know how I'll do it. Need to think on it a bit before I dive in and start turning down parts.

Bernd

[sbwhart]

Ho Ho I'm going to like this one

 

Have fun with the project.

Cheers

Stew

[Darren]

That would make an interesting project Bernd....

Wonder if I could stick the whole Union lathe on my miller 

I'm kidding of course....or am I 

[Bernd]

Don't if it would or not since I have no idea how big your lathe is or your mill. 

But hey you never know untill you try. 

Bernd

[Bernd]

Well I started to modify the two parts from the old South Bend spindle, the bull gear and the pulley shaft.

First I started with the bull gear. I made a stub arbor for the bull gear to fit on.


Next I drilled a 1/2" hole through the center of the stub arbor to put a 1/2"-13 all thread rod through the whole works. A washer and nut holds it all in place.


I turned of the teeth, but when it got to the part I'm pointing to the lathe sounded like some one was beating on the gears with a hammer because to the interrupted cut. What to do?


Why you put your mill to work, that's what. Here I'm milling one of the sides off. That's the hole that the pin was in when you used back gear on the lathe.


And here's the side 180 degrees opposite.


All milled off. Now back into the lathe………….


…………..for a smooth up job.


Next is the pulley part. I didn't want all that mass on the shaft and that includes the gear. It's all one piece. I used the same stub arbor and all thread rod. I center drilled the rod for a live center to help make the setup more rigid.


Another view. I was hoping to be able to see the chips come off.


Taking a .005" finishing cut to smooth up the shaft.


And there we have it all nice and smooth.


Here are the parts temporarily stacked up.


Next will be drilling holes into what was once the bull gear. I need to do a bit of thinking as to how many holes to put in.
I know how I'm going to do it. My question is how many of you can figure out a way to accurately put indexing holes in without an indexer or DRO at your disposal?

Hopefully I'll be able to get it all together before the weekend is up and show you.

I'm going to start a thread in the "How do I" section on drilling indexing holes.

Bernd

[Darren]

Nicely executed Bernd, that was some metal removal there 

I can just see some poor soul having finally removed his stubborn South Bend Chuck along with a couple of back gear teeth crying over this one...

[sbwhart]

Nice one Bernd. 

Love the lathe looks like an old Holbroock is it ?

Can we have a hint on the indexing, have you got some more gears available ?.

Cheers
 

Stew

[Bernd]

Darren,

I guess I could have removed the teeth and saved them. 

Stew,

That is a Logan lathe. Don't know exactly the model, but it's early '70's. Has served me very well. Picked it up from a freind for $1000.00 plus a lot of live steam castings and copper for boilers. I think it was well woth the money.

No gear will be used. I'm going to use a some paper and a measuring tape (ruler).

Bernd

[Bernd]

I did a quick sketch on Autosketch. I try not to use it but it comes in handy for things like this.

I figured I would use 32 holes on a bolt circle of 4.300". That works out to 11.25 degrees per hole. Enough holes for what I would need to do for now. Below is a sketch of the hole location.


So until I get the rest worked out. Keeping thinking about how I'm going to locate the holes. 

Bernd

[Bernd]

Well I screwed up big time with this project. I was going to make it for a 32 hole index, it should be for a 24 hole index. Divides much nicer than 32 and who wants 22.5 and 11.25 degree division. It's only useful in wood working.

So with 24 holes you get a division of 0, 15, 30, 45, 60, 75, and 90 degress and so on. You wouldn't get that with 32 holes. Next I had to dig out my reference for drilling the holes. I remember seeing it in one of the magazines or books I have. While searching for the reference I came across an article on "Make a Dividing Head from a Lathe Headstock' in the Feb/Mar 2003 issue of Machinist Workshop (was Projects in Metal). The first picture in the article looked quite familar, see first pic in this htread. Then I realized it was Steve Wellcome aka "Mainer" that had posted the pic on HMEM. In the article he stated to use 24 holes also. So 24 holes it is.

I did finally find my reference to the article that showed how to originate an index plate for a dividing head. The article is in the book from Village Press (Homeshop Machinist) The Wisdom of Philip Duclos. He has an article on how to build a Model Makers Dividing Head. In it he gives instructions on how to make a template that gets used on the drill press for drilling holes in the division plate.

I gave that a try today and failed at getting good results. If anybody has the book you can check out the method used. I will post a quick write up of how it is done in the next couple of days. It'll take a few pics, and C-o-C's to explain. Also I'll explain why it might not work for me on this particular project.

Bernd

[bogstandard]

Bernd,

Have you thought about 36 holes, 10 deg spacing, also gives you some the nice odd numbers. Then you could make a 'vernier hole' block that would give you the 1 deg spacing. Just like a spin indexer.

John

[Bernd]

Bog's,

The thought here is to just get the indexer going. I've read up on the 'vernier hole' indexer method. Guy Lautard has that written up in his Bed Side Reader books.

If you have a spare moment could you give me a clue as to how I would attch that to what I have now? A quick C-o-C would be nice. Thanks.

What I'm trying to do here is make a quick indexer to use. Then I would like to add on either the worm and wheel like Mainer has done to his or go with the "vernier index" method. First I need to complete this step before I decide on the next step.

Bernd

[Bernd]

Well I've drilled the holes in the part.



It definatly was much easier using the DRO. I even cheated and used Autosketch to get the hole dimensions. But I had it done in a short time.

I then remounted it to see what it looked like.



I've been in contact with Steve Wellcome. He had asked why I turned the shaft with the pulleys and gear on it. After I had reassmebled it I wondered why too. It serves no purpose. The old bull gear fits on quite tight on the shaft.

If you look close you'll notice I drilled the holes a bit to deep and have broken out on the sides. If this get's to be a problem then I'll just make another plate and fasten it to the now new index plate.

Next will come the designing of a index pawl and clamp to keep the shaft from turning.

Bernd

[Darren]

Hi Bernd,

That looks really neat and well done, but when you say you used the DRO I havn't the foggiest how you'd go about using one to do this 

[Bernd]

Lets see if i can explain this.

I know that once I center the spindle over the center of the part and zero out the readout on the DRO, I will need to move the table 2.300" in the X direction and the Y axis you don't move. Drill the first hole. Then I move to the next hole from the cooridinats that I figured out.

Tell you what. Next time you are over to Bogs have him show you how it's done. It'll be easier to show than tell.

Bogs, would you be so kind and show Darren next time he is over how I did this. Thanks.

Bernd

[bogstandard]

Bernd,

That is why you should get a display with a PCD function on it, it saves all the working out. The box does the work, you just turn the handles.


Bogs

[sbwhart]

HI Bernd

Good Job 

Now get the rest finished 

 

Stew

[Bernd]

Bernd,

That is why you should get a display with a PCD function on it, it saves all the working out. The box does the work, you just turn the handles.


Bogs

John,

That would be nice to have, but my CFO won't release any funds for shop improvements at the moment. The machine came with an old Anilam readout. Works for what I want to do right now.

As I said I used the Autosketch cad program to come up with the numbers. I didn't have to figure them out. I remember doing that at work when I did first run part inspection on a coordianate machine. All it had was an X, Y, and Z readout. You had to figure everything with a calculator. Keep the brain active though.

Bernd

[Bernd]

HI Bernd

Good Job 

Thanks Stew.

Now get the rest finished 

 

Stew

Oooo, ow. Ok, thanks for the poke. 

[bogstandard]

Bernd,

I remember when we had a new bridgeport CNC where I used to work, must have been late 80's. The model engineers were queueing up with jobs for it, making division plates for their dividing heads.

It is only fairly recently that the PCD option has been available for us amateurs. Now the cost has dropped, everyone can now have it (at a price). In fact now it comes as standard on most boxes, with mine you have to select on the box what machine it is to go on, so the features for the type of machine are available. But it does mean you can swap the box between machines with just the press of a button.

John

[Darren]

Hi Bernd,

I get the mechanics, just not how to make the calcs 

Ta in advance, you're not getting away that easy.......you started it  by giving us ideas with bits of shiny stuff

[Bernd]

Hi Bernd,

I get the mechanics, just not how to make the calcs 

Are you sure you want to know? I involves trig functions.

Come to think of it I don't even remember how to do the calcs now.    It's been a while.

I cheated by using the cad program to figure the positions. 

Bernd

[Darren]

Oh ok Bernd, I'll let you off, I learnt trigs and stuff once, I have no desire to do it again 

CAD sounds good.....I'll ask John when I see him next. I ask cos I can see me wanting to do this in the not too near future.
I could prob work it out in CAD, but knowing me I'd do it the hard way, 

[bogstandard]

Don't ask me to explain it, all I do is get my Zeus book out and that gives me the formulae to work to. I suppose there are people that can keep such stuff in their head, I am not one of them, thank goodness.

In fact you don't have to go that basic any more, I posted a couple of calculators early on about this project, in the other post,

http://madmodder.net/index.php?topic=701.0

that will do it all for you, very little brainpower required.

John

[Bernd]

Just downloaded that pictcircle calculator. Going to give it a try.

Thanks for the link John.

Bernd