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X-axis drive train for Universal Dividing Head

borne2fly

Hot Rolled
Joined
Feb 7, 2008
Location
California
I'm told that to cut helical gears (suitable for an automotive gearbox) on my old BP I will need a Universal Dividing Head coupled to the X-axis drive .... a coordinated dance between rotation and X-axis travel. Anyone know where I might find a thing like this, or at least the parts for it? The dividing head seems to be obtainable, but I've never seen the drive train for sale anywhere even though I understand that the whole setup was once offered as an option?
 
Generally SOLD new on the makes that offered Universal horizontal mills - with dedicated DHs - the ones with a table that could swing on its two piece saddle to suit the helix angle

Older ideas had these gears open. Later ideas enclosed such in a case made for such

How YOU get one on your mill? You make what ever is needed to do what you want.

Here is my crude approach - see post #507

https://www.practicalmachinist.com/...eaves-klusman-183407/index26.html#post3630358

have fun

Here is what came with your 11,000 lb Cincinnati Universal a 100 years ago

Parts Illustrations.jpg
 
If you think you are going to make auto trany gears forget it, takes a lot machinery than a mill ...Phil

On an "old" BirdPort?

?



Kinda like sucking good, hearty, Dutch pea soup through ... well.. not a dirty cushion-sole GI boot sock nor recycled panty-hose as filtering.... how about a high-silicia firebrick?

Possible, in theory, but Oy!

The preparation and patience required is as stunning as the sucking effort!

:D
 
Thanks for the replies, folks. I had a feeling it was a long shot and this confirms it. Still might follow johnoder's footsteps and cobble one together. This isn't for production, just a wild hair project I'd like to build :)
 
Thanks for the replies, folks. I had a feeling it was a long shot and this confirms it. Still might follow johnoder's footsteps and cobble one together. This isn't for production, just a wild hair project I'd like to build :)

Buy or salvage standard, stock, mass-produced gears made well by experts to high standards.. alter the REST of the project to fit the "good stuff".

When the only low-mass manual gearbox known to stand up to the MOPAR Hemi's of the era was a rare and sinfully expensive "Pont a Mouson" made for use in the Facel-Vega?

We did what we had to do to salvage the OTHER strong one out of a scrapped 1939 HEARSE.

Packard.

Of course.

Toothed wheels don't really need a whole lot of re-inventing. They are "out there" already.

Somewhere...

As-are the experts who have equipment and experience to make them from a blank screen to final QC, proper alloys, proper heat-treat, quickly.

And well.

"Free"? Well. Everybody has bills to pay, yah?

:D

If your really need to "do this", shed the BirdPort.

Acquire the K&T or B&S mill AND all the bits of kit to do it.

Minimum.

'Non-trivial exercise" just to assemble the goods. And then the learning begins.

Can't say as I recommend it, given gearmakers have better ways to do it, and long since, already.
 
If you want to share LEAD (how long a complete turn of the work piece is) I'd be pleased to step you through how that relates to your .200" pitch table screw (BP normal) coupled with the common 40 to 1 DH

There are published tables of leads (and their related change gears) - that came with your K&T or Cincinnati - but these are magically inappropriate due to both having .250" pitch table screws - or even wilder like the 6 mm on my "metric" 2CH K&T
 
I had a friend that needed a gear box for his home built plane. He used a planetary gear set from a common automatic transmission and built a case around that gear set. Depending on your goals that might be an easier solution.
 
I had a friend that needed a gear box for his home built plane. He used a planetary gear set from a common automatic transmission and built a case around that gear set. Depending on your goals that might be an easier solution.

Gives yah predictability off the back of deep-pocket testing, the massive count of units "field tested" any bugs reported, as well.

ISTR the ZF 6-speed in the modest 295 BHP XJ-8L has around 600 lb ft rating. It was used in a Mercedes or several and the blower Jag and even the dual-blower Jag.
Same again Getrag or Aisen-New-Process. The adopters NEED reliable specs. then they do their own tests. Then millions of customers test again.

That '39 Packard three-speed I salvaged from the hearse? I couldn't afford a car to wrap around it. Guy who was to marry the sister of my bud across the street felt his '32 3-window was underpowered with a Ford Flathead? Wrapped his Dad's 300 Series MOPAR around a tree. "Just lucky, I guess?"

Bought the wreck. Hung 8 carbs on that mill "Octogasser" rig. Packard tranny went behind it. Never set a foot wrong. No more weight than that fool thing had in the arse, never enough traction to stress it!
 
When milling a helical gear, besides the gear train to the dividing head you have to swivel the table to the helix angle. Not sure how you plan to do that on a Bridgeport ?


Cinc sold this for that purpose - in case you did not own a Universal. Appears tilting BP style head would do similar as vertical

M1375_01.jpg
 
Buy or salvage standard, stock, mass-produced gears made well by experts to high standards.. alter the REST of the project to fit the "good stuff".

When the only low-mass manual gearbox known to stand up to the MOPAR Hemi's of the era was a rare and sinfully expensive "Pont a Mouson" made for use in the Facel-Vega?

We did what we had to do to salvage the OTHER strong one out of a scrapped 1939 HEARSE.

Packard.

Of course.

Toothed wheels don't really need a whole lot of re-inventing. They are "out there" already.

Somewhere...

As-are the experts who have equipment and experience to make them from a blank screen to final QC, proper alloys, proper heat-treat, quickly.

And well.

"Free"? Well. Everybody has bills to pay, yah?

:D

If your really need to "do this", shed the BirdPort.

Acquire the K&T or B&S mill AND all the bits of kit to do it.

Minimum.

'Non-trivial exercise" just to assemble the goods. And then the learning begins.

Can't say as I recommend it, given gearmakers have better ways to do it, and long since, already.

Finding a collection of gears with the ratios I want and with each pair having the same c-c distance as the other pairs hasn't worked out very well. My first thought was straight spur gears, and I could get away with that at least for my two-speed setup .... four gears, two of each size, just reverse one pair, so .... same c-c distance. And off-the shelf is available. Problem comes in with the 3 or more speeds , now I need to locate more pairs with c-c that matches the others. Only two shafts allowed, so everything needs a common c-c distance. Top gear needs to be helical. Input shaft will never see more than about 80ft-lbs of torque.
 
If you want to share LEAD (how long a complete turn of the work piece is) I'd be pleased to step you through how that relates to your .200" pitch table screw (BP normal) coupled with the common 40 to 1 DH

There are published tables of leads (and their related change gears) - that came with your K&T or Cincinnati - but these are magically inappropriate due to both having .250" pitch table screws - or even wilder like the 6 mm on my "metric" 2CH K&T

I'm all ears for anything you would like to say about this. Like .... what gear ratios you decided to use and why, etc
 
I'm all ears for anything you would like to say about this. Like .... what gear ratios you decided to use and why, etc


The gear ratios are the tools that enable you to create LEADS of a length you want. In my post #507 example, I wanted to have an oil groove wrap around a shaft - and I wanted this "spiral" or "helical" groove to make a full turn around the shaft in about 6".

I came fairly close to the 6" - in fact 5.967"

It works this way on that 6mm table screw on my "metric" 2CH K&T

Since the dividing head has a ratio of 40 to 1 (the little input shaft has to turn 40 turns to make the DH and my shaft turn one turn)

Those 40 turns ( if the ratio from table screw to DH input is 1 to 1) moves the table 40 X 6 or 240mm - about 9.449")

to get to the 5.967" I have to change the ratio from 1 to 1 to 1 to .6315 - to make the DH input turn faster than the table screw

The math to arrive at that is 5.967 / 9.449

The gears that just happened to do this are 38 T on screw and 24 T on input to DH

The math again is 24 / 38 = .63158

The 64 T in the photos is just an idler big enough to connect to the 38 T and the 24 T - its tooth count makes no difference at all

Here is the first page of Cincy's Tables of Leads - a twelve page document that has about 2800 differing gear ratios and LEADS

Cincinnati Leads_01.jpg
 








 
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