# FA-1 derailing problem.



## TonyWalsham (Jan 2, 2008)

I am in the closing up phase of a battery R/C installation into an AristoCraft FA-1.
Went for a test run to day and it kept derailing on AristoCraft turnouts that every other loco that fronts them, will go sailing through. The back to back gauge checks out just a little tight with an AristoCraft gauge checker.
The only thing I can think of is that the power trucks have the separate gearbox that rotates along the motor shaft axis, are mounted inboard. That makes the rigid wheelbase longer.
I always understood that reducing the rigid wheelbase of any loco was a good idea and those rotating gearboxes should be outboard. That is on the ends of the trucks.
Opinions please!!


----------



## Pete Thornton (Jan 2, 2008)

I always understood that reducing the rigid wheelbase of any loco was a good idea and those rotating gearboxes should be outboard. That is on the ends of the trucks. 
Opinions please!! 
Tony, 
Yes, the rigid wheelbase should be minimized. But those FA1 trucks aren't rigid - the pivoting gearbox allows one axle to pivot providing true equalisation. 

If yours is rigid, then something is stopping one axle from pivoting and that will help or cause the derailing.


----------



## TonyWalsham (Jan 2, 2008)

Posted By Pete Thornton on 05 Sep 2012 04:42 AM 
I always understood that reducing the rigid wheelbase of any loco was a good idea and those rotating gearboxes should be outboard. That is on the ends of the trucks. 
Opinions please!!
Tony, 
Yes, the rigid wheelbase should be minimized. But those FA1 trucks aren't rigid - the pivoting gearbox allows one axle to pivot providing true equalisation. 

If yours is rigid, then something is stopping one axle from pivoting and that will help or cause the derailing. 


Yes Pete. One axle pivots, but by design AristoCraft has them on the inside. Looks like I will have to pull the shell off again and reverse the blocks. I hope the screws holes can handle another dismantling.


----------



## Stan Cedarleaf (Jan 2, 2008)

Tony... My solutoin to fix that issue was to put shims in the truck so the one axle would not pivot... Works very well me. 

I've done that on all my locos with that truck.


----------



## eheading (Jan 5, 2008)

Tony I use an alternate method with those trucks than Stan does. To handle my less than perfect trackwork, I always reverse those motorblocks so that the "floppy" axle is on the outward end of the truck on both front and rear. This works phenomenally well on my railroad. I have at least 6 Aristo locomotives operating this way.

Ed


----------



## Greg Elmassian (Jan 3, 2008)

To me, putting the "floppy" axles outboard makes sense, for exactly the reasons given, reducing the length of the rigid chassis. 

I would comment though if you have problems with a locomotive that short, then your trackwork needs help, because you will never get a mikado, E8, Dash9, or the like to work. 

I cannot understand why adding shims and rigidizing the truck helps though, seems like going in the wrong direction. Now both axles are rigid and you have no hope of equalization. 

I only have the RDC-1, RDC-3 and RS-3, so maybe the truck suspension on the FA is radically different? Did not think so. 

Greg


----------



## Naptowneng (Jun 14, 2010)

Very interesting thread, as I have had the same derailing problems with my FA 1 since it was new. It derails on every layout I put it on, including Marty's last year







I recently noticed the same thing Tony observed, that the flexible axle was torward the center on both motor blocks, making the leading and trailing axels rigid. I wondered if rotating the blocks might help thus putting the flexible axel front and rear. Glad to see one person did that with success.

Tony please let us know what you do and how it works!

Thanks

Jerry


----------



## East Broad Top (Dec 29, 2007)

I can't speak to a whole lot of Aristo locos, but I did have the chance to look at Jerry's when he brought it over to my dad's railroad earlier this summer. The trucks on his FA are held very firmly to the frame, so there's really very little room for the trucks to rock side to side to compensate for twisting tracks. It's only those equalized axles on the trucks that can move, but with the trucks rigid to the frame, you've essentially got a long rigid truck that can flex in the middle. That's not going to work on twisting track. Aside from rotating the trucks 180 degrees (which I'm glad to see helps), I wonder if you couldn't put a small 1/32", maybe 3/64" shim on one truck to give the entire truck the ability to rock side to side relative to the loco frame. You don't need much room for rocking, but you do need a little. On the center cab I just finished rebuilding for my dad's railroad, the trucks don't have a whole lot of play, but they do have enough to handle any unevenness in my dad's track where Jerry's would derail. I don't know how the FA trucks are mounted to the frame to know if shimming them in such a fashion is possible. 

Later, 

K


----------



## TonyWalsham (Jan 2, 2008)

The owner of the layout has a fleet of Bachmann logging locos and never has a problem with them derailing, including his 2-8-0.The owner is most fastidious with his track laying. It concerned him that such a small loco as the FA-1 could not negotiate his track safely, so he checked the accuracy of his track leveling, gauge and alignment for errors. The turnout was spot on.

Where I live now is the OZ equivalent of being in the Boonies so this layout rarely ever sees any other locos except when I bring one around for testing.

I will remount the trucks this morning, retest the loco and report back.


----------



## todd55whit (Jan 2, 2008)

Interested to hear what you find. I am mulling over using USA blocks to replace the Aristo blocks on my FA1. Good luck.


----------



## TonyWalsham (Jan 2, 2008)

That fixed it. 
Not easy to physically swap the trucks around thanks to the way AristoCraft have routed the wiring. Still, I took a running dive into the lok and figured out how to do it. 
Must be getting a bit senile in my dotage because now I remember, that is how I fixed the even longer wheelbase RDC that did the same thing. 
IMHO those AristoCraft 2 x axle motor blocks that DO NOT have the axles suspended in the side frames, are the smoothest motor blocks, bar none, on the market. So AristoCraft come out with a sweet running motor block then go and balls up the loco by incorrectly mounting it. Typical. 

Thanks for the comments guys.


----------



## Naptowneng (Jun 14, 2010)

Thanks for the quick feedback, Tony

You mentioned wire challenges...did you have to add length to the wires to do the swap on the blocks? 

I plan to do this mod asap so I can take to loco to Marty's

Jerry


----------



## JackM (Jul 29, 2008)

This thread just proves the value of belong to MLS. 

I'd read about turning the bloacks on an RDC in Greg's website, but didn't really consider doing it until this discussion popped up. My RDC-1, which was the first motive power I bought when I built the first portion of my garden layout, has always has SLTS (Sporadic Leave the Track Syndrome). The past few weeks it found a number of new locations to exhibit this tendency, when my three locos (four, if I count Thomas) have been doing just fine. 

Turning the blocks is now on my "must do" list. 

JackM


----------



## TonyWalsham (Jan 2, 2008)

Fortunately I didn't have to extend any wires. 
This was a mish mash chassis with new no axle trucks on an old chassis. 
I had removed the weight at the back to mount the batteries. That meant all I had to do was drill a suitably sized hole towards the rear to take the two pairs of wires coming from the motor block. 
The front truck was a bit more difficult. Taking the weight off is not easy and requires removing the side frames and the motor block to get at the screws. So I left it alone and routed the wires between the motor block and the mounting saddle. There is barely enough clearance room to do so so I removed enough of the ridges on the underside of the saddle to clear them. Then they could poke up through the original hole through the floor and the weight. Fortunately there was enough length still to reconnect to my new wiring. 
BTW. The loco runs superbly and now tracks perfectly. 

The RDC has the newer weights so will be quite simple to do.


----------



## Bob in Kalamazoo (Apr 2, 2009)

Posted By Greg Elmassian on 05 Sep 2012 09:01 AM 
To me, putting the "floppy" axles outboard makes sense, for exactly the reasons given, reducing the length of the rigid chassis. 

I would comment though if you have problems with a locomotive that short, then your trackwork needs help, because you will never get a mikado, E8, Dash9, or the like to work. 

I cannot understand why adding shims and rigidizing the truck helps though, seems like going in the wrong direction. Now both axles are rigid and you have no hope of equalization. 

I only have the RDC-1, RDC-3 and RS-3, so maybe the truck suspension on the FA is radically different? Did not think so. 

Greg 
I have two FA/FB sets and used to have another FA, I also have two RS-3's. So, a total of 7 aristo locos that all have the same motor blocks and all of them and seem to be mounted the same way to me. I've had all of these apart to install decoders and to change the motor blocks from the old style to the new style in one of the RS-3's and three of the FA/FB's (I think it was two FA's and one FB). All of mine had the correct orientation on the motor blocks to begin with and I stayed with that when I changed from old to new. They all run great on my approximate 500 foot of track. 

Bob


----------



## Greg Elmassian (Jan 3, 2008)

Bob, so your floppy axles are inboard? 

Greg


----------



## eheading (Jan 5, 2008)

Tony, I'm glad that "reversed" motorblocks worked for you too. That was a great idea of drilling the new holes to bring the motor wires directly up into the engine body. I have always just routed the wires around the motorblock and then used the original holes. By bringing some of the wire out of the engine body, I have always had enough wire to achieve this without having to splice into the wires themselves. Sometimes I also just apply a little hot glue to attach the wires to the side of the motorblock to hold them in place. As I've said, even with my poor trackwork, I have never had a problem with these engines (RS3, U25, FA1/FB1) once I reversed the motorblocks.

Ed


----------



## TonyWalsham (Jan 2, 2008)

Drilling new holes can really only be done with the weights removed. 
The cables from the block are just long enough to reach up into the body as long as you make enough room under the saddle for clearance to prevent pinching the wires between the saddle and the motor block.


----------



## Bob in Kalamazoo (Apr 2, 2009)

Posted By Greg Elmassian on 06 Sep 2012 05:56 PM 
Bob, so your floppy axles are inboard? 

Greg 
Shoot, now I feel totally stupid. I thought I knew what I was talking about, but I figured I better go check and make sure that my floppy axles were all inboard. As it turns out, 5 of them are inboard and one is outboard. I really thought I knew that they were all the same. Now I'm not sure which way the one was that I sold . Anyway, they have all run exceptionally well on my railroad. Occasionally I will have cars (mostly passenger cars that will derail but never the diesels. Very seldom my Mallet will derail but that has always been because something has gotten across the tracks. But at this point my credibility is shot so take all this for what it's worth.
Bob


----------



## Greg Elmassian (Jan 3, 2008)

One of the things that made my RDC run much better was removing the traction tired wheels and replacing with solid wheels. 

It seemed from observation (lying on the grass at track level) that on tighter turns, the traction tired wheels would make the truck "pull" unevenly. This would often "turn" the truck as a traction-tired wheel would "grab"... then up and over the rail and a derailment. 

After replacing all the traction tired wheels, absolutely no derailments where there was always a derailment... no other mods needed. 

Greg


----------



## TonyWalsham (Jan 2, 2008)

Greg, 
you are spot on re the traction tyres. 
I believe AristoCraft made these motor blocks both ways. With and without traction tyres. The motor bocks I have been working with have no traction tyres.


----------



## s-4 (Jan 2, 2008)

The biggest problem I have with the FA1 truck is that it no longer rides in the side frame suspension. The original sprung side frames allowed each journal bearing to ride up and down in the pedestals as needed. If you take the same truck and remove the axle ends, you lose all the flexibility....the truck was not originally designed to be mounted to the bolster by screws, it was supposed to float inside the frame, being held in place only by the axle ends in the brass journals. 

Even though the new design still has the side-to-side rotation on one axle, it doesn't work as well because it's not sprung to center anymore. That's why you may be better off to disable the rocking axle. The LGB and USA trucks seem to track better, and do not have this feature....The USA trucks are sprung, which help with uneven track and the LGB trucks have larger flanges to compensate.


----------



## Greg Elmassian (Jan 3, 2008)

If you disable the "rocking" axle, you kill the equalization it can provide. 

3 points will sit flat on any surface, 4 points (4 wheels) will NOT. 

I cannot follow your logic, you say because the trucks don't work well, you should make them even more rigid and inflexible... just does not make logical sense.l 

You say that LGB and USA track better (agreed) and then you give the reasons (agreed), but that's no reinforcement for your previous logic. 

Can you give some reason or justification why locking the flexible axle makes anything better? (I'm taking in general... if you had no possibility of track warp and no grades on curves, I could see it as a "Wash", but this is in general) 

Greg


----------



## s-4 (Jan 2, 2008)

Hi Greg, 
In my mind, the ideal 2-truck locomotive should have trucks which can rock to the front and back with minimal resistance, and may also rock side to side through a self-centering suspension. 

In the case of the current FA design, the 2 fixed axles are always going to stay rigid (side to side) with the car body, and the rotating axle is going to attempt to follow the dips. Unfortunately, I think as the rotating axle settles into place, the whole truck turns slightly off-center to compensate. Perhaps, this is partially to blame for the reduction in proper tracking, as the natural centering provided by the wheel taper is diminished. Also keep in mind, that the rotating axle is incurring a significant torque from the worm gear, trying to flop it one way or the other, depending on the direction of travel and load. This same torque can easily overcome the equalizing (due-to-gravity) and provide you with an equal, but opposite effect.


----------



## TonyWalsham (Jan 2, 2008)

If both trucks could swing backwards and forwards and rock sideways at will, the loco body would continually flop from side to side. Just like the SD-45 (and other AristoCraft 3 axle trucks) could do if you don't make at least one gearbox solid in the block. 

The whole idea of the two axle block is to provide a three point suspension which is not possible if the axles extend into the side frames as the angle of the axle shaft in the suspended end blocks created by the rotation, will cause the end of the axle to bind in the brass journal bearings as those end blocks with bearings can only go up and down and not follow the arc of the axle as it rotates left and right around the motor shaft. That will cause excessive wear in the brass journals 
No doubt it was the excessive wear on those brass journals that prompted AristoCraft to improve the original three point design. 
BTW the later design does allow the truck to rock back and forth but not sideways. The only thing they did wrong was to mount the blocks the wrong way around. They maximised the rigid wheelbase length instead of minimising it. The block has ball bearings on each axle and IMHO opinion they are the best and smoothest motor block drives yet devised by any manufacturer. With the possible exception of the Bachmann Shay and 44T drives.


----------



## JackM (Jul 29, 2008)

re: my comments above - 

My RDC-1 always derailed at a particular spot on a 180 degree curve about 14 feet in diameter; none of my other motive power, or rolling stock for that matter, has a problem there. Yesterday I took the necessary tools out onto the patio and, in the bright summer/fall sun, I turned the blocks around. The RDC can now whiz around that curve at full speed with no problem at all. I am pleased. 

I had tried that curve both with and without the traction tires; it didn't make any difference. But I'll be sure to order the non-tire wheels next time I buy some stuff from one of my favorite dealers, if only because I will eventually run out of spare tires. They do dry and crack and will eventually snap. 

This solution may not necessarily be the solution for everyone, but for me it was an easy fix. If only my cars were so easy. 

JakcM


----------



## eheading (Jan 5, 2008)

I couldn't agree more with what you said, Tony. I think those ball bearing Aristo two axle trucks are an excellent design and when mounted with the floppy axle toward the outward end of the locomotive they perform superbly. I had an RS3 derailing at one point where I actually had some noticable track warp. I could watch the front axle, when rigid raise up in the air when it hit the warp, and proceed to derail. When I reversed the motorblocks and the engine came to that spot, the floppy axle allowed the wheels to follow the contour of the track with no problem. 

Now I know many will say, "you should get rid of the warp". I agree! But I find that over time I get spots that develop warp, and I have to address them much less often when I have motorblocks that can handle it. 

Ed


----------



## Naptowneng (Jun 14, 2010)

Yes!

Went to my shop at 1030 last night and took my FA 1 apart and reversed the blocks. Now running my tight curve (5" diameter) layout for 20 min, and runs perfectly. Thanks to all who contributed to this thread for helping me get this loco back to work and to Kevin for looking at the loco at his Dad's open house.

PS- I found a page from the Otawa GRR club that showed moving the forward MU plug wires on the PCB in order to get the front MU plug to work.

http://ovgrs.editme.com/FA1Wires

I used their nice diagram to assist in the shell removal. I have not used the front MU plug, only the rear one, so has anyone done this? 

Regards

Jerry


----------



## Greg Elmassian (Jan 3, 2008)

yeah, you fixed it just enough to prevent derailing, ha ha. 

If you had looked at the rear axle, I'll bet one wheel came off the rail also, but the flange depth was enough to keep it on the rails. 

As time goes forward, Aristo will probably roll out it's new wheel contour to all motor blocks, and you'll be able to revisit the problem. 

The new wheel contour is on the new Dash 9's and it is really good, probably the best that can be accommodated by the 3 axle blocks. The 2 axle blocks should be able to handle a smaller flange depth, but testing will prove the validity of the theory. 

I've been doing some extensive testing on the new wheel contour, it's on my Dash 9 page. 

Greg


----------



## Naptowneng (Jun 14, 2010)

Just for you , I crawled on the ground at the worst point on my layout, a left 180 degree curve that climbs a litttle and goes into a switch then drops slightly to finish the curve. As best I could tell, all the wheels on the rear block now stay in contact with the rail in that section


----------



## TonyWalsham (Jan 2, 2008)

Reversing the trucks on the FA-1 reduces the rigid wheelbase from 15" down to 7.25". Less than half what it was. 

I was a bit hasty when starting this thread and should have put it in the proper forum that deals with locos etc instead of the battery forum. My apologies.


----------

