Trains.com

F units and their compound curves..

6281 views
14 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    February 2003
  • From: Guelph, Ontario
  • 4,819 posts
F units and their compound curves..
Posted by Ulrich on Friday, November 22, 2013 5:11 PM

As far as I'm aware, EMD  E and F series locomotives were the only ones that used compound curves in their car-body design. Covered wagons from other builders did not. I've read that compound curves were difficult and more expensive to manufacture, hence the boxy squared off designs we see today. With all of the progress in computer aided design and manufacturing we've seen  over the last several decades, is it  likely we will see compound curves again?  Passenger trains of 50 years ago that were pulled by first generation covered wagons looked fast and sleek compared to what we have today.  From an aerodynamic standpoint I'd guess that an FP7 would have been more efficient than any one of the more boxy engines that pull today's trains. Imagine an FP7 design with modern technology under the skin! 

  

  • Member since
    August 2010
  • From: Henrico, VA
  • 8,955 posts
Posted by Firelock76 on Friday, November 22, 2013 6:22 PM

In fact, EMD cheated a bit with those compound curves on their E and F units.  This was accomplished with generous amounts of "Bondo"  auto body putty. 

It's probably unlikely we'll see those compund curves again.  It's a lot easier to weld together "slabsides" of steel, hence the angular look of todays locomotives.  More's the pity. 

  • Member since
    January 2001
  • From: SE Minnesota
  • 6,847 posts
Posted by jrbernier on Saturday, November 23, 2013 9:15 AM

  Those 'compound curves' were created by hammering sheets of steel over a wood block form and welding the pieces to a steel frame.  Lots of 'bondo' material and grinding produced the cab/nose assembly.  IIRC, they were constructed in the Chicago area and shipped to La Grange for assembly with the rest of the car body.  There was lots of labor involved in the construction(money).

  As far as 'aerodynamics - A sleek streamlined nose does little for fuel economy.  A train is like a long shaft.  The ratio of the front cross section to the overall length is pretty small.  But I have to agree that the old covered wagons looked 'cool'!

Jim 

Modeling BNSF  and Milwaukee Road in SW Wisconsin

  • Member since
    August 2013
  • 3,006 posts
Posted by ACY Tom on Saturday, November 23, 2013 9:27 AM

In the 1970's, I had an older female coworker at a Chicago-area hospital.  Her hands were heavily scarred.  She told me she got those scars from working as a welder on those EMD cab unit noses.  I didn't want to pry, so I never learned any more details.  So those beautiful E and F unit noses came at a heavy cost.

Tom

  • Member since
    January 2002
  • 4,612 posts
Posted by M636C on Saturday, November 23, 2013 4:15 PM

There wasn't much hand working of compound curves in the EMD nose.

The upper part which included the  windshield frames and the nose including the location of but not the barrel of the headlight were pressed in the manner of automobile body parts ( but in much heavier material)

These pressings (mirror imaged left and right halves) were used on the Australian locomotives built from 1951 onward but were trimmed by 1-1/2" on each inner edge, giving a body 3" narrower to fit the restricted loading gauge. This is most visible in the windshield centre pillar which was 3" narrower.

The curves themselves were a solid of revolution. The shape of a vertical section through the nose just forward of the windshield was the same as a normal section through the nose (at right angles to the nose angle) below the headlight.

The shape that was rotated was a single large radius curve merged to two sharper radius curves on each side. The actual curves did not change from the original EA in 1937 until the last E9 in 1964. The particular design allowed for both the more angled nose of units of models EA to E6 and the steeper nose from FT and E7 onward.

It should be pointed out that the CB&Q E5 did have a different stainless nose, not welded together. Since this did not use body filler, it can be seen that the basic shape did not require much filler.

Below the headlight there were no compound curves and the panels were hand fitted to the welded support frames. The noses were assembled  on a jig and were interchangeable.

M636C

  • Member since
    August 2010
  • From: Henrico, VA
  • 8,955 posts
Posted by Firelock76 on Saturday, November 23, 2013 7:27 PM

The Burlingtons stainless E5 was a one-of-a-kind unit not repeated for any other 'road.  Stainless is a pain the neck to work with (depending on grade of course)  and after the Burlington project I can well imagine EMD's people saying "Never Again!",  especially after trying to get those compound curves right.

A machinist friend of mine once told me that working with stainless steel can reduce even the most veteran machinist to tears of frustration.

  • Member since
    April 2011
  • 649 posts
Posted by LensCapOn on Monday, November 25, 2013 10:20 AM

didn't MPI use a FRP (aka "Fiberglass") nose cover over an angular welded substructure? This would be a way to get as compound curvy a nose as you want well within current cost standards.

 

 

Never say never.

  • Member since
    May 2013
  • 3,231 posts
Posted by NorthWest on Monday, November 25, 2013 9:33 PM

EMD's F59PHI has a fiberglass nose, over a strong metal frame.

  • Member since
    October 2013
  • 212 posts
Posted by McKey on Tuesday, November 26, 2013 8:43 AM


This ACS64 look quite roundish design too...

Somewhat more than basically the same locomotive for Europe.

  • Member since
    February 2012
  • From: CAPE CORAL FLA
  • 511 posts
Posted by thomas81z on Friday, November 29, 2013 1:22 PM
ACS64 man are they ugly!!!!!
  • Member since
    May 2003
  • From: US
  • 25,292 posts
Posted by BaltACD on Friday, November 29, 2013 4:10 PM

thomas81z
ACS64 man are they ugly!!!!!

Beauty is in the eye of the beerholder.

Never too old to have a happy childhood!

              

  • Member since
    June 2002
  • 20,096 posts
Posted by daveklepper on Saturday, November 30, 2013 6:39 PM

Cannot fault the engineer's ability to see, however.

  • Member since
    October 2013
  • 212 posts
Posted by McKey on Sunday, December 1, 2013 2:49 AM

Watching these Siemens vehicles from close by they are actually pretty neat looking. But, there seem to be some problems with the cameras for all of us, since these appear ugly only in the cameras...

I would swap the American version curves any day to the European version lines, so much more neat design it it. 

Once you get inside, the working environment is SUPERB! At least this goes to European Vectron and I don't think they could have made the engineer sitting partly sideways (unergonomically) on ACS64 either.

thomas81z
ACS64 man are they ugly!!!!!

  • Member since
    August 2010
  • From: Henrico, VA
  • 8,955 posts
Posted by Firelock76 on Sunday, December 1, 2013 9:31 AM

You know, I actually like the headlights on the ACS64!  Reminds me of the headlights on the "Bad Guys"  cars from the old "Speed Racer"  cartoon series!

  • Member since
    October 2013
  • 212 posts
Posted by McKey on Sunday, December 1, 2013 10:44 AM

But none of these are by the looks like the previous generation Tauruses. Below the ÖBB class 1116 Taurus is being washed at Innsbruck Main, Austria last summer.

Join our Community!

Our community is FREE to join. To participate you must either login or register for an account.

Search the Community

Newsletter Sign-Up

By signing up you may also receive occasional reader surveys and special offers from Trains magazine.Please view our privacy policy