How difficult is it to replace a Type E couplers with type H's on heavyweight cars? I'm not a car expert,and would appreciate any info from you knowledgable car folks out there. Thanks in advance!

Once upon a time, I worked for American Steel Foundries, a manufacturer of couplers. I recall once discussing this issue with AT&SF engineers in Topeka, Kansas. I am almost certain the coupler's yoke will require replacement. Also, you'll be required to modify the coupler support plate, replacing the fixed plate with a "sprung" version. Since Type H couplers interlock with each other, knuckles on two coupled Type H couplers cannot slip past each other as the cars negotiate vertical curves. Depending on how the coupler with the Type E head was connected to the yoke, you may also be required to fabricate a new support plate for the pin that connects the Type H coupler to its yoke. If the shank of the Type H coupler is longer than the shank of the Type E coupler it replaces, you'll be required to modify the entire end of the draft sill, perhaps modifying the location and length of the draft gear pocket and, perhaps, enlarging the width of the draft pocket near the coupler head. Designing these modifications will almost certainly require the services of a qualified engineer.

Your going to have to rebuild the whole coupler pocket. If you can find a CS (control slack) coupler from an ATSF lightweight it should be pretty close to a drop in replacement.

If you're going to possibly run Amtrak at any time, you would want to pull one of their PC Inspectors into the design sooner rather than later.

As was stated, you will need to assemble your preferred coupler/draft gear combination, and then design a new draft gear pocket to fit the frame, giving the specified height and pulling face. I've seen both welded in and fastened pockets. What TRS says about the sprung support is also essential. There are parameters for all of this - centerline; striking face; pulling face; etc. - so you'll need to get the numbers. In the past, with carpenters handy, we have mocked things up in wood in order to facilitate fabrication of the pocket.

I've had this web page bookmarked for a while, it looks like the business is dead, but the page remains. It has some discussion that may be useful.

http://www.greatlakesrailcar.com/couplers.htm

Around 1990, when we still thought we might be operating excursions on NS under their requirement to install interlocking couplers, I helped convert some lightweight CN cars with heavyweight-style coupler installations to Type "F" couplers. These cars required a custom-made drawhead with a unique length, which is no longer available. As mentioned in the Great Lakes Railcar posting, you may get lucky and be able to mix and match off-the-shelf freight-car Type "F" parts to make the correct length, or close to it. More recently, we converted a C&O heavyweight combine that had different-length Sharons on the baggage and passenger ends, and we got lucky on one end and came "close enough" on the other, making up the difference in length by lengthening the buffer-plate stems.

Measure carefully before spending money. The dimension that you want is between the working face of the outboard draft-gear stop and the pulling face of the coupler. Remember that you will be changing yokes with the couplers, so the distance to the coupler butt pin doesn't count, and Type "F" drawhead lengths are measured differently from Type "E" couplers.

The geometry of these conversions is difficult to calculate. Remember that two interlocking couplers will have no movement between the coupler heads, and a Type "E" installation probably relied on movement between the adjoining couplers to provide part of the swing. Your new coupler hanger will need to be wider than the dinky little one your heavyweight was probably built with, and you may find the operating radius of the car is limited by the swing available between the two sides of the centersill outboard of the draft-gear pocket. Again, we got lucky and the limits of movement within the centersill matched the point at which the diaphragm supports and carbodies themselves interfered on tight curves.

The coupler hanger needs to be stronger as well as wider. For an Amtrak-legal installation, the coupler hanger needs to withstand a downward pressure of many tons. As usual, I can't remember the number (100 tons?), but it's in the old AAR passenger-car standard A-34. The purpose of this is to prevent telescoping in high-speed collisions. This is one of the two ways interlocking couplers contribute to safety at high speeds, the other being to keep derailed cars in line. Many conversions of old business cars to controlled-slack couplers fail on this point, being for the comfort of the occupants only. You must find a point on your body-bolster casting that is strong enough to graft such a weldment on to.

You actually need to build two coupler hangers: a sprung one that carries the weight of the drawhead only, and a stationary one that only works in a wreck. As a simple guide, emulate the design you find under a 1950's Pullman-Standard lightweight car.

Then you must build an angle-cock bracket and cut lever that move with the coupler. Emulate the design you find on an auto rack car.

For economy and variety of length, you want Type "F" and not Type "H" (Tightlock) couplers, and freight-car draft gear and not the rubber (Waughmat) style. Do not re-use your old, suspect, spring-tyle draft gear. Certified rebuilt freight draft gear are cheap, and come compressed so that you can install them easily. As I recall, we used YF-22s, which are stiffer than traditional passenger gear, but the stiffness may help protect your draft-pocket stops from hard couplings, and the passengers won't notice the difference if your enginemen are any good. Expect to find that your buffers are destroyed by wear or rust under the vestibule floor, and need to be replaced, too.

I wrote all this up for Private Varnish magazine, but have lost my copy and don't recall what issue it was in. I can probably find the article text if need be.

You can see all these conversions at the Steam Railroading Institute. Tennessee Valley Railroad Museum also has a very nice conversion of a heavyweight diner along the same lines, and there are others out there.

Thank all of you for your assistance! I know i'll be asking more questions from you car experts out there about other matters in the near future.