Modifying a Southbend Headstock for Indexing

[Darren]

Thanks John, I must have missed that.....

[bogstandard]

Glad you like it, here is a pic showing the setup figures for a 4" diameter plate with 64 x 1/8" holes based around a 00 centre location.

I don't think you need anything other than this, except an accurate DRO.

Just to clarify, the first column is the x axis (begins with 2.000)(2" from the centre point) the second column is the y axis (0.000)(in line with the centre point). These relate to the centre point of the whole circle 0-0.

Bogs

I have added the prog to the download section, it is free to use as long as it isn't used for monetary gain.
It should be available when it gets authorised by the boss.

http://madmodder.net/index.php?action=downloads;sa=myfiles;u=53

[Darren]

Hi John,

Downloaded the program and it looks a cracker,
Although it didn't help me today as I don't have a DRO 

I was rather hoping it would give the distance between the holes but it doesn't...oh well.
I only had three holes to do this time so did it manually, accuracy wasn't really important in this case so that was ok.

See new post tonight under projects/Lister genset

Cheers Darren 

[Bernd]

Finally got some stock to make the clamp. Go back to the first pic of Steve's pic. You'll get the idea.


Ok, I laid out where I needed to drill the holes and the approximate shape.


Now I needed to line up the straight line I scribed to mill about 1" off the top.


This how I aligned the part. You will need three hands or a pair of vise grips set to grip very gently to not ruin the parallel.


Next two machinist clamps to hold the parallel in place. An indicator to align the part and a large rubber mallet for slight ajustment.


And away we go. The first .200" cut at 3 iches per minute.


Almost there. Another .5" lower and I'll be done.


Ta Da, done. Both sides that is. Now to drill the hole for the cotter clamp.


The next few days I'll be showing how to design a cotter clamp and install it on the part.

Bernd

Modified to get correct picture above. 2nd pic.

[HS93]

ok whats the pink stuff, I have never had any luck with the blue stuff it,s eather streakey or to thick I have just got some new stuff and its no better, or it may be the way I put it on. anyway that looks like it could be different as you have it nice and consistant.

Peter

 

[Bernd]

Peter,

It's all done with mirrors.

Acutally it's the red version of the blue stuff. I got it in a bunch of tooling a guy gave me. It's quite old. It takes a bit to get it smothed out or it'll streak also. The product is "Dykem layout" Red dye 206 or 296. I believe it's the red version of the blue we used at work. Has the same oder. I'm sure that it's quite old, but it still works.

What helps to is that you wipe the part off with some alcohol, not the kind you drink, to clean the surface of any oil and it should go on better.

Bernd

[Divided he ad]

Cool.... Just been through and re-read the whole thread.... Mainly started by looking for this clamp!!

Nice bit of workmanship going on there Bernd 

Personally I would have little/no use for this I think.... 1/ my mill is tiny!... 2/ I haven't even thought of using the dividing plates etc for my rotary table!! .... Maybe someday I'll see a project that will have me using them?

Still want to see what this all looks like when finished.... and what you're going to do with it!!??


Love the pink layout..... You sure it didn't belong to an old gal??     Looks very nice though   



Looking forward to seeing the curves going on 




Ralph.

[bogstandard]

That is a real nice technique you used there Bernd, to get the tangent angle set up in the vice. 

That is one to be stored away for future use.

We learn something new every day

Bogs

[Bernd]

Ralph,

Keep watching. I'm making pretty good progess on it. Hopefully when it's completley done I'll be able to cut spur gears with it.

PINK! That's actually a bright red. I promise to give it back to her when done. 

If you ever find the head of a small lathe remember this thread. You never know it might just fit.

John,

Glad Grasshopper could show the Master a trick. It's not the most accurate but will get you within a degree or two. 

Next comes making the "cotter clamp". I have it desgined on, heaven for bid, Autosketch. It sure helped with the dimentions needed. But before I can make the clamp I have to make a tool that will cut a .750" hole for the cotter to fit in. So stay tuned. I'll be posting on that in the next couple of days.

Bernd

[Bernd]

I had forgotten tha I had these pics on the camera untill I started the Cutter Block thread.

I'm milling a flat spot were the cotter key clamp is going to go. I need a flat spot for the wahers. It'll become clearer as we go.



And here is the part with both sides milled.



That'll be it for this part for a while. I need to make a tool block to make a tool to drill a hole for the cotter clamp. Sound familar when making something. Go here to follow the cutter making process.

Bernd

[Bernd]

Ok, back to making the cotter key clamp. Now that the hole has been drilled I can make the cotter blank.

To start with I'm turning down a piece of .875" (22mm) dia. brass. I had to turn it down some so it would fit on the flat that was milled on the body of the clamp.



Next I turned the body of the cotter to .750" (19mm) dia. to fit the hole in the body of the clamp. Unfortunately the hole that I had drilled with my home made drill was a bit smaller than .750".



Next I turned the dia. for a 1/2"-13 thread and brought the ends down to minimum dia.



Next I set up the thread cutting tool using the thread gage.



Next I blackened up the thread dia. and took a scratch cut to check that the number of threads is 13 using a thread gage.
Yes, it is 13 not 15. They look very close.



The thread was cut and checked until a 1/2"-13 nut fit snuggly.



Here's the aluminum block the brass cotter and a selection of washers and the nut.



This is what it looks like assembled.



And we leave off with a look at what's next, mounting the clamp on the faceplate. It has the cotter in place to be bored out to the dia. of the spindle.



Next I'll show how I clamped the spindle clamp on the faceplate.

Now to get back and do some cabinet work before the wife finds out I'm goofing off.

Bernd

[Darren]

Next I set up the thread cutting tool using the thread gage.



Bernd

So that's how you square up the tool !!!!

Thanks Bernd 

Looks good btw, even though I can't follow where this is going just yet, keep em coming 

[Divided he ad]

Nice work Bernd 

I still have to find the time to have a go at this threading stuff!

I have to ask this though.... Where did the dowel looking bit go?   The one lined up above the pin, next to the nut and flat washer.... I can't remember seeing it's home?


Looking forward to the rest 




Ralph.

[sbwhart]

Nice bit of thread turning there Bernd 

Look forward to next posting. 

Cheers

Stew

[Bernd]

Nice work Bernd 

Thanks Ralph

I still have to find the time to have a go at this threading stuff!

Practice with a larger thread such as the 1/2"-13. Much easier to do than a smaller thread if you've never tried it.

I have to ask this though.... Where did the dowel looking bit go?   The one lined up above the pin, next to the nut and flat washer.... I can't remember seeing it's home?


Looking forward to the rest 




Ralph.

I didn't need to use it. I thought that the washer might not work alone, and that I would need something samller under the washer. But the washer by itself worked fine so I didn't need the drill bushing.

The rest of you guys, thanks for the nice comments. More to come as soon as I do a bit of woodworking in the kitchen (those cabinets you know). 

Bernd

[SPiN Racing]

 



Im watching... and learning (gonna learn to cut threads later today I think)........ BUt I still dont know what it will be. 

[Darren]

Ralph,

I too put off having a go at threading. When you read how it's done it all sounds very complicated. There seems to be quite a lot involved in setting up and actually doing it.

For my first go I skipped some of the procedures.

I cut a 1mm pitch thread on a 22mm dia and it worked fine, easy. Then I tried the same on a 6mm dia. The nut threaded on perfectly.

First I set the lathe to cut the pitch with the change gears. Positioned the tool for the first light cut, locked the saddle nut and switched on. When close to the chuck I simply reversed the lathe motor keeping the saddle nut locked. Didn't retract the tool or use the threading dial at all.
Then advanced the tool slightly and cut the next depth. Repeat till the nut fits.

Easy.....

I'm not saying it's the correct way to do it, but good for starting out as there is a lot less to think about.

[bogstandard]

Darren, there are a few methods for thread cutting that can be used.

One is the straight in approach, which was most probably the one you used, and there is the offset topslide method, which is the one I prefer because it puts less strain on the cutter and machine. But each to his own.

But always, if you are going for low TPI for imperial, or large pitches in metric, it is always better to make the cut manually using a handle on the end of the leadscrew to turn the machine. I have yet to mod my machine, but it will be done in the not too distant future. The reason being, going to these size of threads puts a lot of pressure on the change gears and is liable to smash them. DAMHIK.

John

[Darren]

Hi John,
I did offset the slide, but only cos I'd read about it somewhere and this being a small machine.

Good point on the hand wheel, I must make one for myself as well....

[Bernd]

Ok, I got more done on the index head today.

First pick is of getting the sacrificial faceplate nice and even.



Next I need to get the part somewhat centered on the hole I'm going to bore out. I took a piece of aluminum and put a 60 degree taper on the end. The other end is held in the tailstock by the drill chuck.. The clamps are just tight enough to hold the part in place.



I then use the tailstock to push the part up against the faceplate. This will get the alignment close. After I get it close I use and indicator to bring the hole in to about .001 to .002" run out. Tighten down the clamps and ……………



…….. start boring out the hole to the required dimension, which is 1.625" (41.3mm). It looks like the part is spinning at a high rpm's but is actually on the lowest pulley combo before going to the back gear. I really don't have any idea of speed on this machine. It came with out a chart for speed.



Here you can see the cotter blank being scalloped to the dia of the bore.



And the bore is to size ready for a test fit on the spindle of the index head.



Yup, great fit on the spindle. Just a couple of tenths looseness. Next will be to bore the second hole so it will fit on the shaft behind the spindle. Then the cotter clamp will be finished up.



That's it for now. Maybe tomorrow I'll get the other hole bored to size and get the clamp permanently mounted on the index head.

Bernd

[sbwhart]

Good job Bernd  Nice write up enjoying the thread 

Cheers
 
Stew

[bogstandard]

This is starting to become a superb post Bernd, well written and described, plus the pics take it up a notch or two.

Can't wait to see the finished article.
 
I won't ever make one, but the post is turning into a real good read, just for the techniques you are using.


John

[Bernd]

Thanks for the kind words John.

Haven't done this type of techincal writing in a long time.

The pictures sure help explain a lot. 1 pic=1000 words, right?

Bernd

[Divided he ad]

Cool.... I like it, specially the method for alignment of the hole.... Could take a while with a dti in there?

I now have a clear mental picture as to the cotter clamps design and use.... I was thinking early on "why is it mounted with the pin in it?"   

All understood now..... Been a while since I have seen something like that, possibly will be a while till I do again?

One of these days I'll find a bit of ali that'll do for one of those plates!!



Now then Bernd, my questions are ....

Are you going to use the mill for the smaller bore, or the lathe?  I would think the work would stick out quite far on the lathe?

And how are you going to round the ends off ?

...... Oh the suspence!!   

 


Looking forward to seeing the next bit 




Ralph.

[SPiN Racing]

Very cool.. I see how it will fit.. but will watch this area to see what it does.. LOL

And OMG that chunk of metal spinning like that makes me nervous just seeing the picture!!

Scott