The Radiating Axle

[RoughboyModelworks]

As an aside to the 1:24 Katie project, I've become interested in the Heywood Radiating Axle while waiting for some of the Katie research materials and references to arrive. Katie, being an 0-4-0 was not equipped with these but they were in use on 0-6-0 Ella and 0-8-0 Muriel. I'm working on a 3d CAD rendering of the Heywood system to try to fully understand its construction, and following that, after having been challenged, will attempt to machine a working axle in 1:24, probably more an exercise in madness or the early onset of dementia.  At any rate, having done some research into radiating axles, I thought I'd share a few of the drawings I've tracked down. I don't intend to go into the complexities of each system here. There are good references and discussions of the systems (except the Pfeiffer/Vauclain) in Mark Smithers' Sir Arthur Heywood and the Fifteen Inch Gauge Railway.

A sleeved-axle system patented in 1870 by Englishman John Clark appears to be the first radiating axle system. The Clark system was different to Heywood's and relied on only the axles at the extreme end of the wheelbase carrying sleeves, as did the later German Klien-Lindner system. The illustrations below are from Clark's patent.





The drawings below show the Heywood system, which is the prototype I'm working on. Though I don't have original patent information, it was first employed on the Heywood locomotive Ella, built in 1881.





The Klien-Lindner system was patented in 1892 and employed sleeves on the extreme end axles which could both pivot and slide with limits, and which were fitted with internal side control springs. The drawing below illustrates the complexity of this system. There is a much more complex drawing in Smithers' book, so reduced and complex that it wouldn't reproduce here to anyone's advantage.



The latest system I came across is the Pfeiffer/Vauclain system for Baldwin Locomotive Works patented in 1924. Once again a sleeved axle system using internal side control springs, similar in basic principal to the Klien-Lindner system.





Paul

[Ken Hamilton]

I can't speak for anyone else, but I've never heard of a Radiating Axle system. 
After looking at these drawing for a couple of days it's even starting to make sense....
To see a working model would be WAY cool.
Good luck, WP.

[lab-dad]

Those are some beautiful drawings!
And yes, you have lost your mind!.
This will be wonderful to see in 3-D much less in real space!
-Marty

[Chuck Doan]

Gotta love those old drawings.

[RoughboyModelworks]

Gotta love those old drawings.

Yes, they're great. I've been a fan of technical drawings and architectural renderings for as long as I can remember. I can remember when I was a kid I used to pore over some engineering books in my grandfathers basement storage and copy out technical drawings. I sometimes wish I still had those books, they were full of wonders.

And yes, you have lost your mind!.
-Marty

I am inclined to agree with you Marty... this project just confirms it 

Paul

[marc_reusser]

Great reference material...I had no idea there were so many different designs for these. 

I still need to scan you that KL stuff...sorry for the delay.


M

[RoughboyModelworks]

No problem Marc... I've just been plugging slowly along, things have been disrupted and fairly hectic here lately with family issues. Whenever you get a chance will be fine...

Paul

[MrBrownstone]

Hey Paul,

Was that type of axel only used in narrow guage lines? (for the tighter turns and such?)

just curious

Mike

[RoughboyModelworks]

Was that type of axel only used in narrow guage lines? (for the tighter turns and such?)

I can't answer that definitively yet Mike, but it would appear so from the research I've done to date. The only operative examples I can find reference to are the Heywood and Klien-Lindner systems and they were used on narrow gauge applications. I haven't yet found a railway that used the Clark system (it may have just been speculative) or the Pfeiffer-Vauclain system, even though it was developed for Baldwin Locomotive Works. I'll need to do some more research on the Baldwin application.

It would hardly seem necessary to utilize such a system for standard gauge roads since their curve radii were, by their very nature, more generous than the narrow gauge lines. Narrow gauge was almost always chosen because of limited financial backing, limited right-of-way and more extreme terrain, more hastily constructed roadbed and so on. Also, narrow gauge equipment was generally smaller, lighter for essentially the same reasons. I can't see such a system working on the much larger standard-gauge main-line steam equipment. It would seem that the power and weight requirements of the standard gauge locomotives would be too much for radiating axles. I'm continuing to research the various systems though, so who knows what I might come up with...

Paul

[MrBrownstone]

Hey Paul,

That was very interesting.... and educational too    thanks

Mike

[marc_reusser]

Here's that K-L pic I mentioned.

M

[marc_reusser]

Oh...and in case you wanted to read about it and know it's benefits......

[RoughboyModelworks]

Thanks for the pic and drawing Marc, much appreciated. Would you have any objections if I added it to the radiating axle blog article on the Roughboy site?

Oh...and in case you wanted to read about it and know it's benefits......

Uh, yeah... think I'll have to pass on that but thanks all the same 

Paul

[marc_reusser]

No problem Paul...use away....if you want I can send you a better resolution and larger version of the scan so you can modify it as needed. This came out of an old O&K Catalog.

....too bad about that reading.....mmm, mmm....reeeeaally very interesting. 

In summary:

Better traction even under varied whhel pressure.
Safer manuevering through turns with more constant wheel contact/loading.
Less friction in the wheels when entering and manuevering through a turn/curve.
Runs/functions equally well forward and in reverse.
Equal/balanced/consitent wear in rails and wheel surfaces.


M

[RoughboyModelworks]

Thanks Marc... yes a higher res version would help when you get a moment, thanks.

I figured the text would be something along those lines... undoubtedly some material on proper rotational torque values for the high-compression bumper bolts. 

Paul