Ellis dividing head collets

[Glenn Brooks]

Hello All,

I have a small Ellis Dividing head, but it came with no dead center or collets. Now, apparently it takes B§S #9 collets.

Iam thinking of buying a set off eBay to hold various diameters of round stock. Now, I have no idea how one would draw a BS 9 collet into the spindle. The on line manuals and and parts list don’t show any attachment or parts to draw and hold collets.

Can anyone describe what the idea method Would be to hold a BS collet in this style DH?

Thanks much,

Glenn

[SteveM]

Can you post a picture of the dividing head?

Most of the time a drawbar is used.

Steve

[morsetaper2]

As said above, they use a drawbar. Could be constructed from something as simple as 1/2-13 all thread or a bolt washer setup. Or a more nicely designed setup w/ a thrust washer.

The downside of BS9 collets versus 5C, is that material cannot pass thru the collet. BS9 collets were intended to be tool holding collets. However they will hold stock. 5C & 2J, as an example, were intended to hold stock as the drawbar threads onto the collet exterior.

[SteveM]

The downside of BS9 collets versus 5C, is that material cannot pass thru the collet. BS9 collets were intended to be tool holding collets. However they will hold stock.

With a name like morsetaper2, I guess he would be the expert.

I have a B&S9 adapter, and while it's not a collet, a quick check with a ruler estimates that you can bury stock into the collet somewhere between 3 and 4 inches, so while it's not a pass-thru, it's not like you have only an inch to use.

I've gotten into arguments with the Atlas/Craftsman crowd on the utility of MT3 collets in the lathe. They argue that they are useless because you can't pass stock thru them, but that's not the point; the only collets larger than 1/2" you can use on an Atlas or South Bend 9 or any of the other MT3-spindled lathe is a morse 3 unless you go to an expensive collet chuck. Having MT3 sizes above 1/2" up to 3/4" can prove to be handy.

Steve

[morsetaper2]

With a name like morsetaper2, I guess he would be the expert.

Steve

Expert I am not!

Just sharing my experience. I use to have a BS9 dividing head. I saw a 5C capable div hd in use and the light bulb went on. I had to have one. There are a few of them out there, but uncommon. Ellis, Elgin, Hardinge, if not one or two other makers. And they can be pricey.

Back to the OP's question. Buy at least one collet. Look at handwheel drawbars for inspiration on how to use a thrust washer in its construction. But you could use a bolt and appropriate washer to draw the collet closed in a pinch.

[SteveM]

You can always mount a small 4-jaw on a straight arbor to go into the collet. They you can mount anything you want and get it centered.

Jim Rozen posted a drawing on practical machinist of his homemade Pratt & Whitney drawbar with a needle roller thrust bearing held captive with an internal clip. I searched but couldn't find it, but maybe you will have better luck.

Steve

[Glenn Brooks]

Steve and all,

Thanks much for the info. I’ll likely use the DH from time to time to make replicas of old square headed bolts that I break during my reconstruction of an old time loco. Plus, make up custom length bolt heads- think 3/4” -1” tall bolt heads for capscrews. So thinking collets are an optimum way to hold small (1/4” to 3/4”) threaded shanks.

question: how come DH tailstocks are not adjustable side to side, like lathe tailstocks? Seems like one still needs to align DH work along the axis properly. So far,haven’t seen one DH tailstock that does this...


Making this replacement cap screw got me to thinking about the collet approach....

Glenn

[SteveM]

question: how come DH tailstocks are not adjustable side to side, like lathe tailstocks? Seems like one still needs to align DH work along the axis properly. So far,haven’t seen one DH tailstock that does this...

My guess is because the dividing head is generally used on another tool that has movement in that axis, so they additional capability would just be duplicative.

Steve

[NP317]

And might both the dividing head and matching tailstock have indexing features to fit the slots in mill tables?
RussN

[Rich_Carlstedt]

Glenn, There are collets for the Ellis Dividing Head
I have both the Ellis and the collet adapter and draw bar and took a picture for you
The adapter in the brochure is a straight bushing with a # 9 B & S taper OD with a 3 C Collet bore
My Adapter has a Knurled collar on it which you can see in the pic, and it does not have a handwheel on the Drawbar
Rich

Ellis Collet Adapter

Ellis Collet Adapter

Ellis Catalog page

Page Detail

[Harold_V]

question: how come DH tailstocks are not adjustable side to side, like lathe tailstocks? Seems like one still needs to align DH work along the axis properly. So far,haven’t seen one DH tailstock that does this...

My guess is because the dividing head is generally used on another tool that has movement in that axis, so they additional capability would just be duplicative.

While that's a point, I suspect it's not the valid reason. In truth, the majority of these devices are built with keys, so they self center. If the tailstock is able to be offset, you'd have no idea if it was on center, or not, so making them without adjustment simplifies setup. If, by chance, one has need to offset the tailstock, the keys are easily removed so it can be randomly placed. That's far less likely to be needed than a setup with the center in (assumed) alignment.

H

[Glenn Brooks]

Thanks all for your comments. I have a spare drawbar very similar to the one posted by Rich. So will try it tomorrow, see if it fits the Ellis DH. I acquired it in a misc box with my Burke #4 mill, but it doesn’t fit. Maybe I get lucky on this one.

So looking at Rich’s photo of the original brochure, the Ellis DH requires both the Ellis adaptor, plus the C 3 collet series... I don’t remember the bore in the Ellis to be big enuf to accommodate both. But I’ve never really looked at the bore in detail, it’s always had a nice little three jaw attached. I might have one or two C3 collets in my mystery tooling drawer. Add to the list of things to followup tomorrow.

Still not convinced the non adjustable tailstock will work. But obviously the designers thought it would, ' so good enuf for me!

Thanks all for helping me figure this out.

Glenn