What kind if splined shaft is this ?

[Anatol]

I wasn't sure where to put this question.
I have a (mid 1970s American) winch/windlass - company is long gone. It has an unusual splined shaft (It's ~ 1" OD, inner shaft is ~ 0.75") and the splines are semicircular in cross section. Has anyone seen one like this, know the name it goes by or went by or in what context it was mostly used? I'm hoping to find or make a mate/socket for it.
As for making a socket, I'm guessing the best approach would be to drill the six holes on the circumference of the ID circle, then bore the ID. Then harden.
thanks!

 

[Herbiev]

Looks like a PTO ( power take off) shaft from a tractor.

 

[Anatol]

Thanks for the tip. I googled around. Tractor PTOs are that shape but tend to be 1 1/8 or 1 3/8 -bigger.But that led me to the right terminology for further searches. " 1 inch 6 spline coupling" is getting me closer, but haven't seen any half round spline shapes.

 

[BaronJ]

Hi Anatol, Guys,

That spline was done on a horizontal mill with a shaped cutter. Simply held between centres and rotated for each pass. That would have been done with one cut for each spline.

 

[goldstar31]

As Baron says 'female' on horizontal mill but a shaper to do the 'male'

Personally, I'd like to see it done.

Cheers

N

 

[Barnbikes]

Probably had something like this on it.

https://www.steinertractor.com/ABC1...NUv_arpzuMebsl7-g2AXLgVTHav5qtBwaAnR7EALw_wcB

 

[BaronJ]

Hi Norman,

Haven't you got that the wrong way round ! You would do the male part on a horizontal mill and use a shaper or slotter to do the female part.

 

[goldstar31]

Hi Norman,

Haven't you got that the wrong way round ! You would do the male part on a horizontal mill and use a shaper or slotter to do the female part.

Comes from being born in a thunderstorm.

My excuse, anyway

N

 

[Chiptosser]

Anatol,
I would try it your way, should work fine.

 

[BaronJ]

Hi Anatol,

I just realised that I didn't answer your last question. Yes ! Drilled holes on pcd, bore and file as needed.

If you make it a good fit you probably wouldn't need to harden it.

 

[DJP]

And if the fit is not tight use some green Loc-tite for shafts. You will need to heat it for removal.

 

[nel2lar]

looking at the splines, I've never seen on as such but could it be a badly worn spline shaft? The spine shafts are made that way for ease of disconnect. Farm machinery use it as a prime universal way to drive all their equipment, except for the modern hydraulic drives. I believe a straight female splined should work fine.
Nelson

 

[Anatol]

Probably had something like this on it.

https://www.steinertractor.com/ABC1...NUv_arpzuMebsl7-g2AXLgVTHav5qtBwaAnR7EALw_wcB

interesting, thankyou! - but that is a 10 spline and the splines are square/trapezoid section

 

[Anatol]

looking at the splines, I've never seen on as such but could it be a badly worn spline shaft? The spine shafts are made that way for ease of disconnect. Farm machinery use it as a prime universal way to drive all their equipment, except for the modern hydraulic drives. I believe a straight female splined should work fine.
Nelson

No, the shaft not worn, it was made that way and is very clean. Aside from this being a practical problem for me, I'm trying to understand why the designer made the splines that profile. It is a high torque low speed application. A gearbox or gear head DC motor would have driven the shaft. But like you guys, I've never seen a splined shaft like it.

 

[Anatol]

So - Chiptosser, BaronJ and all,
"Drilled holes on pcd" this is where I reveal my long experience in making but learner status in precision machining. Lets say I want to make a tubular female-female coupling to go on a motor shaft with a keyway. Say 5/8 shaft. Let me check an order of operations with you -

I'll start with a piece of 1.5" dia bar, say 3" long (sorry for imperial measurements).

square up ends and mark centers on lathe
clamp piece in rotary table on mill
drill my 6 holes on pcd 1.5" deep
bore or drill 5/8 hole straight through
bore or drill 1" hole 1.5" deep, cutting away half of pcd holes.

Now for the internal keyway on the motor end.
How do you cut an internal keyway? - found it in a nice vid here (gotta love youtube)

amusingly called 'long boring process' - very apt
so you just scrape it out! (using a boring bar)

And of course, drill and tap for 2 or 3 set screws.

sound about right?

 

[Cogsy]

You don't want 3 set screws - 2 at 90 degrees is best. For the internal keyway, the 'normal' way is to use a keyway broach, but for one-offs they're expensive so the scraping method is used a lot, usually employing a cut-off blade rather than a boring bar.

I don't recommend gloves on the lathe (or any such rotating machinery) like the guy in video is using. They might keep your hands clean but they could cost you a finger, or worse. Not worth the risk in my opinion.

 

[BaronJ]

Hi Anatol,
I made this for my mill table drive, it fits directly on the leadscrew in place of the handwheel.

And this is the tool that I made to cut that keyway. The HSS toolbit is located in a slot milled down one side of the round shaft. The shaft was chosen to be a good but loose fit in the bore of the workpiece. The idea being that it would guide the cutter and reduce any deflection. In practice the tool was sufficiently rigid for me to use it to cut several other 4 mm keyways into some steel gears, one of which was a stainless steel one.

The actual cutter is a length of 4 mm square tool steel with the end ground almost flat.
I originally used the tool in the lathe saddle to push it through the workpiece whilst it was held in the chuck.

In this picture you can see how I used a M2 hex socket grub screw to adjust the cutter depth. This picture was taken before the tool bit was ground into a cutting edge.

This picture shows how I secured the tool bit and how it allowed movement.

 

[nel2lar]

Anatol
I do not see any reason you could not take and use a wider tool and grinding the round profile into it and when pushing it through the hole cut the sides of two teeth at a time rotating 6 or 8 times to produce the coupler you need. Keep us up on the progress.
Nelson

 

[DJP]

What's missing in this thread is the final use of this winch. Does it even need a spline coupler to fulfill it's new task of coupling to a drive source? Perhaps welding on a flexible coupler will get the job done for the life of the winch. Or is this a restoration project that needs to be original?

Just curious.

 

[Anatol]

Hi Anatol,
I made this for my mill table drive, it fits directly on the leadscrew in place of the handwheel.
.

Thankyou fro the pics, that's a nice piece of toolmaking!