Dividing Head help

[gtrackParticipant @gtrack]

Hi

 

I have a few projects in the pipeline that i`m going to need a dividing head for, I`ve very little experience of these but have studied there use and application and it all seems to make sense.

 

I`m really after some advice, from peoples far broader experience than mine, as to what makes/type you would recommend. I have a Bridgeport mill and would not be venturing into the world of spiral gear cutting etc just yet, so that function can wait a while.

I would mainly be using divisions from 2-100, pretty unlikely to go over that in the foreseeable future. So I am aware I would need something that I can get plates for. Most of work I have planned will fit in 3 jaw 4/5 inch diameter chucks easily, the work pieces being up to about 150mm (using adapters to mount in chuck)…if thats of any consiquence (spelling!)

 

One of the lads has been talking about a `Hardinge`……but I also would like the option of having the fast division function as well, but the drive from machinery is of little use to me….Do you think these would be too large for my uses, maybe a Vertex one?…are they any good?

 

So, if anyone has any advice on what I should look at, or what they use on their Bridgeport…it would be much appreciated.

 

(Sorry the post is a bit long winded….i`m avoiding the rain outside!)

 

 

[gtrackParticipant @gtrack]

[David Clark 13Participant @davidclark13]

Hi There

Don’t buy a Hoffman.

The recomended grease that locks the spindle is in the low hundreds.

A Vertex BS1 should be fine for most work except it has a screw-on spindle nose.

Best to buy an old industrial one with bolt on chuck.

regards David

 

[Steve GarnettParticipant @stevegarnett62550]

Posted by David Clark 1 on 06/09/2011 09:28:48:

Hi There

Don’t buy a Hoffman.

The recomended grease that locks the spindle is in the low hundreds.

Well now I’m worried! I picked up a Hoffman very cheaply recently (crazy to let it go). You need grease to lock the spindle? Mine seems to lock up fine. What is so special about this grease that seems to cost rather more than I paid for the head?

[David Clark 13Participant @davidclark13]

The special is that Hoffman won’t tell you what it is and charge the earth for it.

Perhaps your spindle has grease in it.

Sounds like it locks hydraulically.

regards David

[gtrackParticipant @gtrack]

Cheers

 

Anyone know how `good` the Chester BS-0 ones are?

 

Incidentally, what is the difference between a BS0 and a BS1 dividing head, except for the cost!?

 

David, does the screw on spindle nose mean I can not get a chuck for it?

 

Thanks.

Edited By gtrack on 06/09/2011 16:46:42

[David Clark 13Participant @davidclark13]

Hi There

You can get a chuck, almost any chuck but you will need to fit it to a threaded backplate.

Same mandrel as a Myford.

With a thred, it could undo.

regards David

[Tony Pratt 1Participant @tonypratt1]

Hi gtrack, conflicting advice comng up! Hoffman dividing heads are excellent, I used one for 20 plus years in industry and they are a quality item, in fact my favourite dividing head when on the Bridgeport. You can easily disengage the worm and worm wheel so the work can be indicated quickly, also it has a 24 notch disc for the direct indexing of common divisions, my work one also had the attachment for the differential indexing of a large number of divisions.

 

The spindle lock is hydraulic and I had no problem with it in again 20 plus years, I have one purchased off Ebay stripped down in my garage as another project when I get round to it.

 

I currently use a new Vertex BS-0 which is ok but not in the Hoffman class, the worm and wormwheel can be disengaged but only after you take off the sector arms and division plate. The Hoffman has a bolt on and the BS-0 has a screw on chuck which again is ok just remember to plan you machining so the cutter/drill tends to tighten the chuck!!

 

I believe the BS1 is bigger all over and can accomodate a lot more divisions.

Tony

 

[gtrackParticipant @gtrack]

Thanks chaps

 

I am right in thinking this `Hardinge` one is a `Hoffman`? Or have I missed something?

 

I like the idea of the Vertex as it seems easy to get parts/back up for….on the other hand the older stuff seems built to withstand a nuclear blast.

 

I really like the idea of the 24 notch`s, I`ve been reading up on the cincinnati ones, they seem awfully large…and a price to match!….but that function will help me out with the everyday things I have in mind.

 

Does the Vertex have a direct index function?

 

I wont lie, the hydraulic cost thing is concerning me a little, this could be why they seem `cheaper` than the others of the same type/size and i`m concerened one in my price range may have this as a defect;.

 

Cheers

[Tony Pratt 1Participant @tonypratt1]

Hi, slightly muddy waters here. No, Hardinge is an American manufacturer and Hoffman is a German manufacturer. The Vertex does have a direct indexing facility, basically a pin slides into one of 24 holes, but as I said you have to remove the sector arm and division plate to disengage the worm and wormwheel on the BS0. Cincinnati heads are excellent also but very very heavy and I would suggest too big for a Bridgeport. I have just remembered that Hoffman spares are very expensive if you ever need them, Vertex I don’t know about the spares situation.

Tony

[BogstandardParticipant @bogstandard]

I’ve been using a BS0 for about 20 years, and have had no problems with getting spares, it has never needed any. They are almost bombproof.

 

There are a few numbers that you can’t get with the supplied plates, but I solved that problem by making up plates with the missing numbers on them. There was a place at one time that sold 1/8″ thick plates with all sorts of hole sets punched thru them, a set of four, and they gave me almost all my missing numbers, just had to make a central boss to fit, so that I could use them on the BS0.

 

I am just about to fit it out with a stepper for use with my Divisionmaster, so it will be good for hole numbers from 2 to 9999 at the press of a few buttons.

John

 

Edited By Bogstandard on 06/09/2011 18:57:21

[gtrackParticipant @gtrack]

Thanks guys

 

Think i`ll opt for the vertex then, seems to cover all I want/need….Tony, i`ve studied some pics and see what you mean about bit fiddly for direct index, but as an amateur hobbiest I have plenty of time (and at the moment patience) so I`m sure I can live with that……I can always think about `upgrading` if I need to in the future.

 

BS, good luck with the stepper set up, that sounds very nice and i would imagine easier when all done……maybe one day i`ll do the same, but at the moment i`m having enough trouble with the on/off switch!

 

Thanks again.

[BogstandardParticipant @bogstandard]

Gtrack,

 

It’s not good luck at all, I’ve already converted my rotary table (Vertex 6″) and the dividing head is basically the same mechanically.

 

For anyone who has a bit of a problem turning handles and remembering where they are up to, it is a godsend.

 

The thing with using any dividing system is not the operation, but if you ever get disturbed and the concentration lapses, you can soon be up to your neck in it. It is an operation that requires no interruptions.

 

 

John

[gtrackParticipant @gtrack]

John

 

Sorry, I didnt mean good luck in that context….I didnt realise it was a `common` conversion, I thought it may have been a bespoke type alteration…..

 

I know how you feel about concentration lapses….I`m having quite a few myself at the moment!

 

Regards

 

James.

[John Stevenson 1Participant @johnstevenson1]

Over the last few years I have had a fair bit to do with dividing heads and rotary tables, I was instrumental in helping Tony Jeffree in the testing of the Division Master when he was doing it, since been passed on to Lester Caine, in fact my DM has the serial number 00001.

 

First off to correct a misconception the Hoffman head which is very good only requires any suitable hydraulic oil to the lock and then only every 99 years [ or so ] Even the manual states the grade or it’s equivalent.

 

The Vertex is also a decent head and is very easily converted to stepper drive, as mentioned it’s not as easy to get to a free wheel position but all the heads that are able to disengage mesh easily are usually a lot larger, remember as the head tilts it gets taller and with a chuck fitted you can soon run out of daylight.

 

 

This head which is often in daily use as it swaps between the big CNC and the Bridgeport has purposely had the lock and the detent indexing pawl removed as it could cause problems, the 40:1 reduction and the energised stepper is enough to keep it held firm.

 

Something you may remember we talked about when the simple CNC head was covered in MEW recently.

 

If you don’t want a tilt facility then you are probably better off using a horizontal / vertical rotary table as these are lower profile and you have the best of both worlds.

 

John S.

[gtrackParticipant @gtrack]

John

 

Thats what you call a dividing head, would guess theres pretty much nothing that couldn`t divide up…..

 

I keep hearing that the vertex is the way to go, for my usage. I see you can get backplates for them (same as Myford apparantly) so I think i`ll just make up jigs of sorts as alot of the things I am doing will be repeatable…..

 

The only thing i`m a little confused on still is the difference between the BS0 and BS1….other than as pointed out, I think one is larger than the other. Most people seem to recommend the BS0, so that`ll probably be the one I opt for.

 

Thanks all for taking the time to offer me advice.

 

James.

[John Stevenson 1Participant @johnstevenson1]

Only differences between the BS0 and the BS1 is size and the BS0 ‘might’ have a reduced number of holes on the plates. Standard set has 3 plates with 6 rows per plate.

 

Some heads like the Hoffman have two plates, either two separate or one thick double sided plate with 9 rows per plate

 

Early BS0 had a Brown and Sharpe taper and a weird thread on the spindle.

Late and current models have a MT2 taper and Myford thread but check first as it depends on the supplier.

 

BS0 is nicely sized for home shop machines such as the X3 and similar sized machines.

 

Genuine Vertex is made in Taiwan, be wary of some of the Indian sourced rotary tables.

 

John S

[Phil PParticipant @philp]

I use an Elliott universal dividing head and it will do pretty much anything I need.

 

The only reason I have this is because I couldn’t find a decent 3½” Hoffman at the right price when I was looking for one.

My dad swore by the Hoffman, and I would think if you can find a good one it would be better quality than any of the imported stuff.

But its horses for courses, if you only intend to use it once a flood, then maybe a budget one will be just fine.

 

By the way I also use a Hoffman indexing rotary table, and its a super bit of kit.

 

Phil

[Steve GarnettParticipant @stevegarnett62550]

Posted by Tony Pratt 1 on 06/09/2011 17:24:51:

The spindle lock is hydraulic and I had no problem with it in again 20 plus years, I have one purchased off Ebay stripped down in my garage as another project when I get round to it.

 

 

After all these dire warnings about grease, etc I fished out the one I got – and it doesn’t appear to use the same locking system as any of the ones I can find pictures of. It just has a straightforward clamp around the edge of the shaft. Yes it looks original, and yes it definitely says (and otherwise looks like) a Hofmann. It’s not a particularly large one and it’s only semi-universal (no external drive shaft input).

 

Ever come across one of those?

 

 

[John Stevenson 1Participant @johnstevenson1]

That one of mine in the picture above is a Hoffman with no external drive shaft.

Not sure what mine has as the lock lever ? has been replaced with a lifting eye.

 

The book I have on mine does say though that it needs hydraulic oil type BP HLP 50 or similar.

 

John S.

[Steve GarnettParticipant @stevegarnett62550]

Needless to say, mine doesn’t have a book. But if yours has a lifting eye instead of a lock lever, is that what you have to lock it with? Seems a bit weird, that!

 

I’ll do a couple of photos.

[Steve GarnettParticipant @stevegarnett62550]

I think that just the one photo will suffice…

 

‘Standard’ clamp ring… nothing hydraulic about it at all.

[Dinosaur EngineerParticipant @dinosaurengineer]

I,ve just received Hofmann's latest UTH dividing head operating instructions and as J.S. mentions, spindle clamping oil is specified as BP HLP 5. This is a pre ISO std. spec. but any hydraulic 32 viscosity would be suitable which is cheaply available ( about £5 per L). My head is the small non differential geared type similar to Steve's. This latest op.instruction is slightly different to my old head but the essentials are the same. Does anyone know what spec is the outside spindle taper fitting for chuck mounting ? I intend to make new chuck back plates. Seems that very early heads,the spindle lock was done by clamp ring and not by hydraulics.

These heads were only supplied as std. with 1 division plate (13-49 holes) with the 2nd plate, (51-99 holes), as optional extra. The std plate covers all divisions up to 50 and many above with the 2nd plate covering all divisions up to 100 and many above this.

I can well understand that a lifting eye is a desirable feature as even the small head is heavy, but at the expense of no spindle lock ?!! Maybe spindle locking on J.S.'s head is done by turning the eye bolt ?

Happy days .

 

.

 

 

 

Edited By Dinosaur Engineer on 16/12/2015 16:58:05

Edited By Dinosaur Engineer on 16/12/2015 17:00:01

[EmgeeParticipant @emgee]

Hi Dinosaur

The Hofmann head I had the division plate was drilled both sides, have you ever had yours off ?

Emgee

[Nigel McBurney 1Participant @nigelmcburney1]

I have had a hoffman head for twenty years,complete with differential indexing kit,and capable of spiral milling,it has been very good for stationary engine spiral gears,must have done at least one hundred,only used the differential dividing once to make a 127 gear so that the head can be used on a metric mill . reading these posts I just went down to the shed and had a look at my hoffman its about 100mm centre height, the lock does not work,it makes it a lot more difficult to turn the spindle,but it will turn.the lock is bottoming on its shoulder so cannot be screwed in further. The lock screw is vertical and central to the locking collar,and when I took the lock screw out there is a bright spot in the centre of the screw,opposite and underneath there is a tapped hole but I could not see if there is a socket screw down the hole,I have no instructions so I would like to know where to fill it up and how much oil is required? My dividing plate is double sided and there are jacking grub screws to push the plate off its spigot, only one thing that spoils this head,the plastic parts,i.e. indexing fingers and index plate clamp,ok they have stood up to a lot of use,with exception of a small tapped hole in the plastic which stripped.

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