Experience with jump (lift) frogs - and steam?

Looking at a project where the host railroad is quite twitchy about putting in a permanent turnout to serve a museum site... and have suggested a jump frog instead of a conventional frog for less maintenance expense on the railroad part. Either that, or they insist on removing the turnout after the equipment is moved in, huge expense.

I'm quite aware of the problems with self-guarded frogs and blind drivers. I'm not aware of any existing museum site where jump (aka lift) frogs have even been suggested. If anyone has any experience with these, please speak up. Most times I've seen steam quite flexible enough to negotiate the vertical drops at turntables, this isn't that much different, I don't think.

We're talking about this:
https://1.bp.blogspot.com/-Jm5Szl5atpM/ ... 600/18.jpg

You're really only lifting the wheelsets up around an inch for the flange depth, depending on the strength of the guard rail on the other side to guide the wheelsets. It 'should' work, but I'll still poll this crew.

I'm aware of the lift diamond out at the California State Railroad museum, we were involved with that, close, but not quite. Here I have more lateral forces on the inside of the flange opposite the frog.

I don't think any modern equalized steam locomotive would have any trouble with one of those. Note that the issue isn't the vertical accommodation, but the cross-level accommodation where one driver in a pair goes up and the other stays on the flat -- pedestal liners can't be too tight-fitting.

At typical slow speeds going into museum trackage, the flange shock shouldn't be a problem, nor should loosening tires. That presumes no one emulates Strasburg and runs over the switch at too high an inattentive speed... ;-}

Just to clarify for those who haven't seen one of these in person, the other rail on the diverging route should have a hump beside the frog so both wheels on each axle stay at the same level, there shouldn't be much if any horizontal lean.

How does a jump frog compare to a pair of 'butterfly' rerailers? For better or worse lots of steam locomotives have climbed up those over the years.

I took a SD70 over one of these the other day at work, they're not just for cars or light MOW equipment.

If I recall correctly, the Museum of the American Railroad in Frisco, TX, had a jump frog installed on their switch that connects them to the BNSF Madill Sub. They took a couple of steam locomotives - notably Big Boy #4018 - over it. I don't recall hearing of any issues with it.

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You and me both. The thing is, for occasional museum moves at low speed this might be minimized, particularly if the equipment flanges are not sharp. I'd think that something relatively simple that would 'take' the stress of flange contact, perhaps like that steel block, could be laid over the rail to prevent direct contact...

I've thought the same things, and have looked at the 'dings' on a couple of the lift diamonds out there.

I think the truth may be 'well, compared to what?' on the impact loads. I remember a CP over CN conventional diamond I saw up at Brampton, ON on the two-track CN main line. CN was hitting it at track speed and was the senior track, CP was the junior and had to pay maintenance. They had a track maintainer shed right beside the diamond, and the CP track maintainer said everything had to be tightened up and repaired weekly. CN sold the line to Orangeville, and they got stuck with an inherited maintenance bill on that diamond that about killed the project then. I never saw a set of diamonds get so beat up anywhere else. Ideal case for a lift one.

My old-stomping grounds. They did get one, I guess it's one of the most famous in North America at this point. And last I recall, there was a "scar" in the CN rails.

The Orangeville & Brampton is still going, last I checked...

Prior to that I remember watching all kinds of tie bolts jumping out of their holes as CN trains passed over it.

So yeah, one hell of a beating.

And any track maintainer's shed was long gone by 2000, if not earlier.

As that diamond set is right beside the road, I found it on Google Earth Streetview.

Wow, you're right, a double-track lift diamond, and at something I didn't think they could do, almost pure 90 degrees.

I think I was there maybe..... 1998? When CP still had it pending the sale. Rode the hirail up there, and we waited for several trains to cross. And that entire diamond set was a 'jumpin. Thanks for reinforcing my impressions.

While OWLS (One-Way-Low-Speed) diamonds are arguably topic drift from the original "jump frog" subject, the Brampton OWLS Diamond is rather interesting:
https://www.google.com/maps/@43.685957, ... ?entry=ttu

It's similar to the diamond where SEPTA's double track number 11 trolley line crosses CSX's single track main line through Darby, Pennsylvania.
https://www.google.com/maps/@39.9177436 ... ?entry=ttu

Note how the trolley wheel flanges have cut grooves through the head of the CSX rails.

Conventional diamonds used to last a mere two or three years at Darby. The OWLS diamonds last about twice as long, which still isn't saying much.

/s/ Larry
Lawrence G. Lovejoy, P.E.

Scratch that, the Orangeville and Brampton has been shut down, the last train ran on December 17, 2021 (I've been gone for a while...).

Now they're gonna turn it into a trail...

Sad that North America continues to tear up its railway infrastructure. Here in Europe I've never seen so many trains in my life, and the investments they make into these systems is massive! Anyways...

There is a set of three 90 degree One Way diamonds at Rondout Ill.

The North / South (flangeway) route is triple track former Milwaukee Road, with CP, Amtrak and Metra traffic. It is a relatively high speed route.

The East / West (flangeway-less) route is the single track, former EJ&E. I believe it has fairly light traffic currently (according to a nearby CN employee a couple of years ago, it had a couple of trains a day).

In addition to the scarring of the rail, I've wondered about the flanges. Seems like this arrangement would be kind of tough on them, as well.

JR

Here's a video of the diamond in Darby including trolleys and a CSX train with the Orange Juice cars head out.

https://www.youtube.com/watch?v=iRakYWDe2tw

The trolley is the senior rail line here, dating from the 1850's as a horsecar while CSX (B&O) dates from the 1880's.

Phil Mulligan