Fixed Pilots - What are they?

On traditional O gauge diesel locomotives, the pilots on diesel locomotives in particular are mounted to the trucks and pivot with them accordingly.  In real life, that is not the case except for a few rare exceptions.  The pilot is a rigid part of the frame and the coupler is frame mounted.  The main benefit in 3-Rail O gauge is that having the coupler pivot freely with the truck allows them to handle much tighter curves.  The downside is that it looks less realistic.  Having a frame mounted pilot works in O gauge, but does increase the size of the minimum curve the locomotive will handle without derailing any cars it pulls.

As far as the coupler is concerned, most O gauge locomotives (fixed pilot or otherwise) have spring loaded "self centering" couplers.  They'll pivot when needed but return to center normally.

Fixed pilot:

Fixed pilots are a way of providing a more realistic appearance to our models. In the case below, both are Lionel F3s but the stock swinging pilot has been replaced with a fixed pilot. There are pros and cons to this conversion, with the most prominent results being a more prototypical appearance and resulting performance. There lies the rub… a more realistic performance may not be for everyone as they may limit the swing of the truck resulting in the use of larger radii curves and switches, as well as the use of couplers, such as Kadee brand, which will further limit the minimum curve and will increase the amount of per-unit cost because of both the additional work needed to fix said pilots and couplers, and the cost of the additional details themselves.

Tis a slippery slope.

F7 before…

and after…

some of the work in progress…

Good luck in whichever path you decide.

Thanks!

- Mario

I should mention that some applications are easier than others.

For example, easy diesels to add fixed pilots are early Atlas F units, which included scale pilots with each purchase, and most 3rd Rail locos, which also have scale pilots included.

Next easiest are applications where fixed pilots are available for purchase. Again, some Atlas and MTH diesels while not sold with fixed pilots, called 2-rail pilots in offerings where said diesels were offered in both a 3-rail and 2-rail version, were available for separate sale. I was able to purchase said types of parts from both Atlas for my RS-1 and GP35, and MTH for my GP35. While not completely plug-and-play, they do offer easier installation compared to the third option, below.

Most commonly and a difficult application is where a pilot spacer, lowering of the locomotive frame, or both, may be needed.  Lionel tended to just separate the pilot from the body and increase the ride height slightly to allow for a swinging pilot. In most modern diesels, this can be fixed by lowering the ride height and the. Having a thin spacer between the frame and pilot, or like the early F7s, lowering the ride height to scale height and mate the pilot to the frame, aligning the two.

Most difficult, in my book, was the adaptation of an aftermarket pilot, such as taking a P&D Hobby passenger pilot and cutting it, mating it to a 3D printed adaptor, and then mounting to the Lionel F3s shown above as the 1606 and 1607. At least 100 man hours have been out in to getting them to look good and matching photographs of actual locomotives.

With that said, you cannot argue with the results:

What application are you looking at?

- Mario

I miss Farmer Bill's humor.

@CentralFan1976 posted:

I was able to purchase said types of parts from both Atlas for my RS-1 and GP35, and MTH for my GP35.

What application are you looking at?

- Mario

Are these still available?

Dave

@illinoiscentral posted:

I miss Farmer Bill's humor.

As in pilots that can no longer reproduce? 

My examples of some fixed pilots that came from the factory that way and ones that I've done myself.

I think if you have broad curves the fixed pilots add a lot.

Hint #2… Start with your steam engines!

Most steam engines have a scale non-functional coupler on the front that you can keep or swap out for a function coupler, and just need a spacer and coupler box on the rear. See @Norm Charbonneau for ideas on  adding a Kadee style coupler box to the rear of your tender.

- Mario

@Greg - Mi posted:

Does a fixed pilot keep the coupler centered during operation?  Why is or isn't a fixed pilot better that a regular pilot?

Thank you Greg

As said above, a fixed pilot and Kadee Coupler make the locomotives appearance more realistic. It does introduce some issues with regard to the curve sizes used in your layout.

For this discussion, keep in mind that the curve measurements are to the center rail/centerline; Lionel FasTrack is measured to the outside rail and is 5/8" sharper on the radius (1 1/4" on the diameter -- "O" number). Where the traditional largest curves offered in O Gauge tubular track pretty much ended at 36" Radius (O-72), that is a starting point when using fixed pilots. Usually you have to move up to 42" radius (O-84) for diesels and 56" radius (O-108) for medium steam. There are some exceptions like MTH diesels (I've personally verified these) and the modern scale-wheeled Big Boy. Now, fixed pilots using hi-rail wheelsets muddies the waters a bit, but not by much. You also need to use scale couplers on rolling stock you wish to couple to the locomotive (a "transition car" with a scale coupler on one end and a hi-rail coupler on the other works).

Bottom line is if you need to use curves sharper than 36" radius (O-72), you probably don't want to run with fixed pilots.

When I first saw 3 rail on hi rail track, I was a little kid. They were running around the Sears Roebuck store and I thought they were great.

Decades later I went to a train show after deciding that HO trains were too small for me to work with anymore. I saw a modern -8 diesel I believe, going around a layout with tight curves. Being up on a table allowed me to see that something wasn't right. Watching the huge, protruding front coupler going by, and seeing the steps move, convinced me to keep looking.

I mean, why??? None of my smaller HO scale engines were built like that.

I got a beautiful MTH O scale 3 rail non-powered SD80/90 MAC in CP colors to decide further on. I loved most about it, just not those pilots and couplers. So I looked into 2 rail O scale. Looking around this site and getting advice from the very posters above, sealed the deal for me. Lucky for me MTH around that time, decided to get back into engines with scale wheels and fixed pilots. I bought all that I could.

......

There are many posts about fixing pilots on the 3-Rail Scale Model Trains forum.  Central Fan 1976 and others have  posted many times about their projects fixing pilots.

I can't stand diesels with swinging pilots and oversized lobster claws.  Guess that's why I only have one diesel and it's a small switcher with fixed pilots.

On a less serious note, what about a broken pilot? You know, zinc pest, that accidental dive off the table, that switch that got thrown and you rammed full speed into another engine or cars?

When you fix it, is that a "fixed pilot"? I know it doesn't take long in this hobby to collect some engines with a "fixed pilot" either actually repairing the pilot or bolting on a new one from replacement parts.

Don't get me wrong, I own a lot of expensive scale trains, like to run 072 and larger curves, and appreciate scale details. That said, I also deal with a huge segment of the train enthusiasts between club members and local repairs that cannot run or choose not to run large diameter curves, complain when a stiff coupler derails their cars, and "fixed pilot" definitely means repaired pilot, not a body attached non articulating pilot.

Again, I own engines with fixed pilots- both definitions.

Every 3-rail toy train layout owner and club that I know has O-72 or smaller curves on their layout.  This pretty much means that swinging pilots are necessary to reliably run all trains.  I agree that fixed pilots are the best looking if a person has the room for large curves.  NH Joe

@New Haven Joe posted:

Every 3-rail toy train layout owner and club that I know has O-72 or smaller curves on their layout.  This pretty much means that swinging pilots are necessary to reliably run all trains.  I agree that fixed pilots are the best looking if a person has the room for large curves.  NH Joe

I agree, this really comes down to what the person wants to run, too, and this is a fundamental argument we constantly have about why people don't go to 2 rail scale. If you want to run fixed pilots with kadee couplers and scale wheelsets and have curves O72 or less, the rolling stock and engines you can run will be limited, pure and simple. If for example you are okay with running small diesels and steam engines, and smaller cars (here I am assuming body mounted couplers, not truck mounted), then it can work with smaller curves. But if you want to run larger diesels and steam engines and larger rolling stock, you couldn't do that with smaller curves.

3 rail, even scale, often uses tricks to allow running bigger equipment, truck mounted couples, blind drivers, larger flanges, swinging pilot allows something scale to run on smaller diameter/radius track. The traditional O 3 rail also was semi or non scale, much of it was built to near S scale proportions for that reason, a shorter freight car or engine can traverse smaller curves without looking ridiculous or decoupling.

Again all about tradeoffs. Even in the smaller scales this was done, lot of freight cars had truck mounted couplers in HO and N for example. Lot of people even in HO and N run into limitations with the space they have, too; they just don't generally have available the trade offs 3 rail toy trains took, other than truck mounted couples, so in HO and N it generally comes down to limiting your choices to the curves you have. The advantage there, especially with N, in a space that would be tight for O, you can have much broader curves (an O 54" diameter curve in N would be 27" radius, which is pretty generous in that world).

Williams FA's; fixed pilots; used a spacer (as you can see).

Old work. I decaled/painted these (WBB had not offered the GM&O's yet. Grrr.)

I like the way that the 3RO (Electrocouplers, BTW) just peek out. They barely swing on 0-72.

Loco on right has correct headlight style for the first FA's ever built, all of which the GM&O owned. All their later FA's had the more familiar headlight on the left.

T/A Studios TMCC in both locos; Railsounds; run as a "lash-up", forgive the non-RR term. Yes, I see the flaws in my stripes. NOT gonna re-do this for the sake if my sanity.

@D500 posted:

Williams FA's; fixed pilots; used a spacer (as you can see).

Old work. I decaled/painted these (WBB had not offered the GM&O's yet. Grrr.)

I like the way that the 3RO (Electrocouplers, BTW) just peek out. They barely swing on 0-72.

Loco on right has correct headlight style for the first FA's ever built, all of which the GM&O owned. All their later FA's had the more familiar headlight on the left.

T/A Studios TMCC in both locos; Railsounds; run as a "lash-up", forgive the non-RR term. Yes, I see the flaws in my stripes. NOT gonna re-do this for the sake if my sanity.

Really wonderful work.  I see that you have both 2 and 3 rail track.  Will the locomotives run on both tracks or just 3-rail?  NH Joe

@New Haven Joe posted:

Really wonderful work.  I see that you have both 2 and 3 rail track.  Will the locomotives run on both tracks or just 3-rail?  NH Joe

First, thanks for the compliment.

Second, it's rather a misleading photo. It was basically taken on a photo "diorama" (a stretch) that I did years ago. I used 2R track because it looks better and nothing was ever going to run on it. I plopped a piece of handy 3R track down next to it for this photo. I have sometimes regretted using the 2R, but it just looks so good.

They are both 3RO locos.

@D500 posted:

First, thanks for the compliment.

Second, it's rather a misleading photo. It was basically taken on a photo "diorama" (a stretch) that I did years ago. I used 2R track because it looks better and nothing was ever going to run on it. I plopped a piece of handy 3R track down next to it for this photo. I have sometimes regretted using the 2R, but it just looks so good.

They are both 3RO locos.

Use 2-rail track?  Hmmm…

Great idea!

Is anyone manufacturing spacers, maybe 3D printed, or other techniques,  so that I can fix pilots on my locos?

I have fixed pilots on my Williams F3 and F7 locos, but the bottoms of the pilots sit too far off the rails to look as good as they might with a spacer.

Been out on the covered deck for awhile. But when it hit 90 degrees, it feels much better down here in the cool basement checking out the OGR forum.

Anyway, I guess I’m one of the oddball, non rivet counters who prefer swinging pilots over the fixed. I like having tighter curves and watching the front end of the diesels come apart as they take the curve, then watch them re-align into one piece again as they straighten out. I like being able to get my diesels into tight places on the layout with ease, regardless of how it looks.

Call me crazy, but IMHO, non-fixed, swiveling pilots is one of the joys of operating toy trains. If I want to see non-swinging, prototypical fixed pilots, I’ll run up to the Union Pacific yard and watch real trains. 😉

If the only thing people notice are your pilots, then your layout needs some work.  With railings the size of sewer pipes on some of these engines I guess I am missing something.

I was reading an article yesterday about the introduction of the U36B at Lionel in '74.  It was basically, yeah we know it is way short but we need it to fit on the GP7 frame.  Somehow the swinging pilot did not make it into the conversation.

Everything is about how much money are you willing to spend on a 'toy' train.