TOS Dividing Head

[Darren]

You'd have a job to pick it up, never mind TOS it  

My new acquisition is this TOS Dividing Head at a "walk the other way" 68Kg !!
OK I didn't realise it was going to be this heavy when I bid for it on Ebay, but it's mine now so I guess I'd better see what all the fuss is about  



It was taken apart to split into two parcels, one at 50kg and the other at 16kg. Otherwise it would have been pallet delivery.

As it was already partly dismantled I decided to strip it down for a good clean and re-lube. The old grease had dried somewhat and it was rather stiff to turn.
Here's the nose, 2.5" x 6mm thread (a mix of standards) The bore is 40mm and the nose has a 5MT taper.
I'm looking for a 5MT/5C adapter if anyone knows where I can get one? Both my lathes are 5C so this would be really handy for transferring work without loosing concentricity. Grizzly has them for $30 but won't ship to the UK for orders under $200  



It came with one indexing plate. It's not the correct one for this unit and someone has done some bodging to make it fit/work.



It looks like the TOS DH used plates with four fixing screws (can anyone confirm this?) so at sometime someone removed the fingers and made a crude adapter. The fingers are now of course missing and need to be made.



Because the plate has been moved forwards by the plate adapter the indexing pin has been crudely shortened. This will need to be repaired in due coarse.



The spindle .... a size any lathe would be proud of !! Note the taper used to lock between indexing positions, between the nose and worm gear.



Bottom of this picture is the direct "quick" indexing ring that fits just behind the spindle nose. 24 holes should prove quite useful.



And here it is after a quick clean-up  



I also gave the degree angle face a quick clean, can read it now  



Well that's it for tonight, all cleaned up, re-lubed and rotating quite freely now  

Next job to remake/repair the bits and bobs ....

[75Plus]

Darren,

Have you seen this article? It may be helpful.

http://www.metalwebnews.com/howto/collet/collet.html

Joe

[Darren]

Thanks,

I've seen a couple of similar pages about making the adapters. If I had a 5MT lathe it would be quite simple as the lathe could hold the adapter whilst machining the internal 5C taper and thus machining it accurate.

But I'm not sure how I can do this as my lathe is 5C.  

[websterz]

Could be worse...could be a POS dividing head. 

[John Stevenson]

Could be worse...could be a POS dividing head.  

Didn't know Bridgeports made dividing heads ?

Darren,
It was probably modified because the original plate would have been massive to reach out to the pawl bracket that does the differential indexing. The original plate, probably only one and double sided ? would have had a section of teeth on the out so you cam move so many holes and reposition the plate with the pawl to get prime numbers.

A plate this size would mean it always has to hang off the table.

Believe me you are better off as it is and don't want to go that route, it's the first step to madness 

John S.

[Darren]

Thanks John,

I assume having the plate hanging off the edge of the table wouldn't be an issue with a small mill like mine. But on a larger production machine I could see it being an issue.
I'll stick with the plate I have and source/make others as needed and 6" seems reasonable for my requirements.

At the moment it spins and I need some way of locking it in place. Did the original use the bracket to the right to grip the edge of the disk 

[John Stevenson]

Yes there is a little pawl that fits into *teeth* on the edge of the disk.

Easiest way with what you have is to drill an index hole in the plate just inside the smallest circle and into that pawl bracket, fit a pin and job's a good un.

What's the block for with the gear attached in the first few pic's ?

John S.

[AdeV]

Thanks,

I've seen a couple of similar pages about making the adapters. If I had a 5MT lathe it would be quite simple as the lathe could hold the adapter whilst machining the internal 5C taper and thus machining it accurate.

But I'm not sure how I can do this as my lathe is 5C.  

Darren - my lathe is a 5MT spindle taper, you'd be welcome to pop over the Dee & have a play here if you like? Of course, you will have to take into account that my lathe cuts a taper when it's supposed to be cutting straight.....

[Darren]

Yes there is a little pawl that fits into *teeth* on the edge of the disk.

Easiest way with what you have is to drill an index hole in the plate just inside the smallest circle and into that pawl bracket, fit a pin and job's a good un.

What's the block for with the gear attached in the first few pic's ?

John S.

Right you are then John, pin it I shall 

That lump is the gizmo for the spiral milling gears driven from the mill leadscrew, as the rest of the parts are missing, and I doubt I would use it anyway I will leave the lump off to save some weight.
Not that I'd notice this minor reduction !!

[Darren]

Darren - my lathe is a 5MT spindle taper, you'd be welcome to pop over the Dee & have a play here if you like? Of course, you will have to take into account that my lathe cuts a taper when it's supposed to be cutting straight.....

Thanks for the offer Adev, lets see what crops up and take it from there. I may have to make my own yet !!

[AdeV]

I may have to make my own yet !!

Aye - that is what I meant: If you want to make your own, feel free to use my lathe with it's 5mt spindle to cut the inner 5c sleeve...

[Darren]

Thanks Adev, much appreciated be nice to meet in person, I'll get back to you nearer the time   

[Darren]

It seems that a MT5/MT2 reducer is the same price as the MT5/5C adapter before I even attempt to bodge one up 

Why are Grizzly being so difficult with shipping to the UK? Are times that good over there?

[AdeV]

No problem, I'm here pretty much 24x7 - at least, it feels that way... shame all too few of those 24 are actually around the machines!

Speaking of which, I'm skiving off work to cut that deep aluminium hole right now..... back soon 

[Darren]

Started the repairs tonight with the little job of fixing the indexing pin tip that had been badly ground down.

Took it apart



Stuck the pin in the lathe, faced off the mess, drilled and tapped 4mm



Inserted a threaded rod. The pin needed to come forward as so much had been ground/machined away so I added a 4mm nut for support. I ended up using three nuts in all.



Turned the threaded bar to 3.5mm to match the dividing plate holes and trimmed the nut.



And here it is installed. Enough there to trim back again if/when it should wear. What's more the tip is in effect replaceable should I come across more plates with different diameter indexing holes.

[Dean W]

It seems that a MT5/MT2 reducer is the same price as the MT5/5C adapter before I even attempt to bodge one up 

Why are Grizzly being so difficult with shipping to the UK? Are times that good over there?

Darren, if you are unable to find one in the end, I'd be willing to act as a go between to get a MT5/5C reducer shipped your way.  You would have to order it and have them ship it to me, then I could send it your way.  Any package up to 20 pounds is about $44 shipping charge from my place to yours, but it would keep the total price much less than that $200 minimum.  It still sounds like a lot, though.

Dean

[Darren]

Thank you for your kind offer Dean, it very much appreciated. Another member in the US has offered to pick one up for me and send it over.

I must admit, I did think about ordering several from Grizzly to meet their $200 min order and stick the rest on Ebay to recover my costs. Your minimum shipping sounds expensive but then we have discussed that before on this board. I think to send it from this way it would be about $15 or so?

Thanks
Darren

[Darren]

As stated previously this is not the correct plate for this DH. The TOS plates have 4 screws and most others inc this one seem to have 3.

So, off to drill four holes then. Set up on the RT clamped down with a socket and bolt  The plate seemed to be made from cast steel, anyone know if this is normal?



Holes were countersunk and all seems to fit quite nicely. You may note that I've breached two of the existing holes. Well not the holes just the countersunk areas. Try as I might this was the best spacing I could come up with. Next time perhaps I'll only make/use two holes as that should be enough.



Now with the plate fitted I needed a spacer to stop the cranking arm pressing against the index plate shaft.... confused?  all will be come clear ..

A bit of bar stock .... well you do like pictures don't you 



The bush from within the bar stock



Fitted



Not easy to see but the bush now holds the indexing arm off the plate mandrel.




I have not been too pleased with my pictures lately, most of them seem to be out of focus. Today I changed lenses and this one seems to give better results. Bit of a sod to use though as it won't focus any nearer than 0.85m. The other one got quite close. It probably doesn't help that it's quite dark in the workshop (photographically speaking) and lit only by florescent tubes.
Can you see any difference between this post pictures and the previous ones?

[Darren]

And finally for this evening I needed some way to lock the index plate from spinning.

This is what I came up with, similar to John Stevensons idea except this way I won't need to drill every plate exactly to match the pin.

Drilled 4mm through the iron casting and into the steel spindle. Then tapped 5mm. The spindle was then rotated so the securing bolt was away from the drilled area on the spindle. Lock the bolt down and we are good to go  

Just need to sort the chuck and backplate and this tool will be perfectly serviceable. Later I will make some indexing fingers to make life easier, but for now it can be used without.

[John Stevenson]

Darren,
Just for a heads up that plate is off an Elliott dividing head, they are easily spotted as they have 9 rows of holes and two plates per set.
Most have 6 rows and three plates per set.

Here's the chart for an Elliott


http://www.stevenson-engineers.co.uk/files/Elliott%20Dividing%20Head%20Chart.pdf

John S.

[Darren]

Thanks John, that is good info to know and that chart printed off for the workshop will be handy 

[Dean W]

I don't know what the deal is with our shipping rates, Darren.  I looked on the postal site and it only gave flat rate boxes for 20 pounds or less.  Same price for all weights.  Too darn much.

Glad you got something sorted out.

Dean

[Darren]

Nothing done tonight, just a lot of umming an arring  

The backplate does not fit the chuck by miles ..



There are two sets of mounting holes in the chuck, I'm pretty certain that the chuck had six mounting holes and someone has added another three to get it to fit this backplate.
What do you reckon... does that sound about right ... ?

How on earth they expected it to fit true .... there's no register.

I'm pondering whether to have a go at re-threading this backplate I have or if to make an adapter plate to go between the original backplate and chuck.
Ideas and suggestions welcomed .... pleeeease .....!



It's a Swedish chuck and was prob once a very nice bit of kit .... looks well battered now and has a few chunks milled in it. So it could never be used on a lathe again due to balance issues. You should be able to read as much as I can from this picture. Any ideas of the make anyone?



I decided to test the runout so stuck a collet in my lathe to hold a 25mm bar and clamped the chuck to that. My lathe has less than two tenths runout and I was measuring 15 thou here.



So I may just trim the register up to true the chuck. Well it'll be true at 25mm at least. What do you reckon, good idea or not?

[Dean W]

Maybe chuck it up on a few different sizes of stock and check the runout.  I suppose it's possible you just happened to chuck up at a bad place on the scroll.  Sound reasonable?

Dean

[Darren]

Yes Dean, entirely possible.  
I suppose I would hold smaller stock in a collet, so really if anything is done to the chuck then it should be at a larger diameter.

On another note, I spent some time in the workshop tonight and made the MT5/5C collet adapter. Woohoo punch the air   -... mighty pleased with it too. Just drop it in the spindle under it's own weight and you can't get the bugger out again as it's stuck fast.

If only you saw how I did it you'd wonder it works at all    
I've yet to test the run-out but I suspect it'll be fine. Too late now, I need to go climb the wooden hill ....