I received a pair of replacement trucks today for a Kadee covered hopper. I want to make sure that I do the installation correctly, so I am looking for help and advice from members familiar with, and experienced in, installing these trucks.
Here is the pair of trucks with mounting tabs still in place holding the mounting screws.
One set of instructions talk about making some modifications to the bolster on the underside of the car body.
When those instructions say to "cut off flush" and "be sure top of hub is smooth and flat, are they saying to file off the four little pyramid shapes around the screw hole, as shown in the third photo?
I appreciate any knowledgeable help and advice. No speculation please!
Rich
Alton Junction
Here is the other set of instructions. Some of the terminology confuses me. For example, when the instructions say, drop the centering bushing into the truck bolster making sure the triangle wedges are indexed properly, I go blank.
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Removed as there is now a better specific discussion.
Everything you need to know about how these trucks work can be found by referring to the relevant patent:
https://patents.google.com/patent/US7434518
You can clearly see there only has to be 'one' sideframe and bolster assembly manufactured; two of them interlock together mutually, with the two half-cylindrical bearing areas defining the 'working' surface for truck pivoting. That is why the truck bolster is in two pieces like that.
The upper part of the bushing acts as a fixed pivot pin, of somewhat larger OD and bearing surface than usual, and the flange acts as a stop to keep the truck frame from coming off. The self-centering action is simply a consequence of introducing wedges and grooves that induce the truck to swing wheels-parallel when lifted completely past the 'bearing zone'.
All the alignment issues have to do with getting the wedges on the bearing pin at the right angle that the trucks 'center' to. This does not matter to the truck performance in normal running. It only affects the angle the truck assumes when the car is lifted.
Removed as there is now a better explanation.
As the owner and operator of about 800 pair of Kadee trucks, I will go out on a limb here and suggest that I am qualified....... At least a third of my Kadee trucks are the self centering type.
Rich, the self centering truck, as you have likely seen by now, has a bushing that the truck pivots on.
The hole in the truck bolster that receives the bushing has V shaped recesses on each side.
The bushing has matching V shaped protrusions on each side.
For the initial installation of the bushing, it does not need to be perferctly positioned, it simply needs to fall down into the little V in the bolster.
Then install the screw, most of the way, but not fully tight.
Hold the truck in a straight position as if the car was on straight track, pull the truck away from the car, this will engage the V of the truck bolster with the V of the bushing.
Holding the truck in this position, tighten the screw.
Flip the car over and let the trucks hang free, the should be in a straight line with the car body.
If not, loosen the screw very slightly, and turn the truck as far as it will go in the direction necessary for the adjustment until the bushing turns slightly,
Retighten and recheck.
When the car is sitting on the rails, the little V notches do nothing, they only engage when the car is lifted to "center" the trucks, in theory making it easier to place it on the rails.
The self centering feature itself is of marginal value in my mind, but, the fit of the bushing in the bolster is much better than just a screw, or even the bolster flange on the "average" freight car.
The self centering feature works the same on both sprung metal, and HGC equalized versions of Kadee trucks.
Questions are welcome, pictures may be possible if needed.
Sheldon
Rich, since I don't own any Kadee hoppers, did the trucks you removed have the center bushing or just a screw?
The answer to this will effect the solution to the four little points on the car bolster.
As soon as I can, I will check out one of my Kadee box cars.
At the moment I'm away from the shop but I DO believe those three "nubs" can remain on the center sill/car bolster of your hopper car.
The part of the "centering bushing" that engages the carbody has four indents in it (you can see evidence of them in my caboose photo in the "Six Wheel Heavyweight" thread.
I will confirm this in an hour or so when I return to the layout room.
Good Luck, Ed
Now, having explained all that so that you hopefully have some idea of how the truck mounting works, it should be possible to simply install the trucks, with the screws, bushings and clips still together as the come out of the package. Screw them on to the car part way, remove the clips, and the pick up where I described the procedure for centering the bushing.
This should prevent the HGC truck two piece bolster from coming apart.
But generally, the clip on brake rigging does a good job holding them together in any case.
gmpullman At the moment I'm away from the shop but I DO believe those three "nubs" can remain on the center sill/car bolster of your hopper car. The part of the "centering bushing" that engages the carbody has four indents in it (you can see evidence of them in my caboose photo in the "Six Wheel Heavyweight" thread. I will confirm this in an hour or so when I return to the layout room. Good Luck, Ed
That's what I am thinking as well, but my inventory of Kadee cars is limited.
Kadee's instructions made the installation sound a lot more involved than it actually is. Basically all you need is a flat mounting surface on the body bolster, and a properly sized hole for the replacement screw. Given that it's a Kadee car, you shouldn't have to make any adjustments for coupler height.
If the new trucks work OK on the stock bolsters, no additional modification should be required. If the protrusions on the car interfere with truck movement, trim them flush.
I've installed quite a few of Kadee's HGC trucks. They're a great solution for cars that have poor reliability caused by the truck/body bolster interface.
Rob Spangler
ATLANTIC CENTRAL Rich, since I don't own any Kadee hoppers, did the trucks you removed have the center bushing or just a screw? The answer to this will effect the solution to the four little points on the car bolster. As soon as I can, I will check out one of my Kadee box cars. Sheldon
richhotrain When those instructions say to "cut off flush" and "be sure top of hub is smooth and flat, are they saying to file off the four little pyramid shapes around the screw hole, as shown in the third photo?
richhotrain Is that correct?
That would be correct:
Kadee_hopper-bolster by Edmund, on Flickr
The instructions are aimed at those modelers who choose to retrofit Kadee self-centering trucks to any number of different designs of mounting bolsters out there. They can't possibly hold the hands of every modeler who attempts to perform such a task. The instructions are simply a guide that indicates a flat surface is required for the "centering boss" to engage with.
If you already own a piece of Kadee rolling stock it would, it stands to reason, be designed to accept a Kadee truck.
This shows the centering boss if it were to be installed without the truck so you can see the indexed points at 90° intervals that engage the mating points on the carbody.
Kadee_centering-boss by Edmund, on Flickr
I hope that helps, Ed
gmpullman At the moment I'm away from the shop but I DO believe those three "nubs" can remain on the center sill/car bolster of your hopper car.
richhotrainDO believe those three "nubs"
Again, I was away from the shop and looking at your photograph on a less-than ideal internet connection.
richhotrainThree? Or four?
FOUR
Kadee_Four-nubs-1 by Edmund, on Flickr
(The far-right "nub" in your photo was difficult for me to see clearly)
My Mistake, Ed
gmpullman richhotrain Is that correct? That would be correct: Kadee_hopper-bolster by Edmund, on Flickr The instructions are aimed at those modelers who choose to retrofit Kadee self-centering trucks to any number of different designs of mounting bolsters out there. They can't possibly hold the hands of every modeler who attempts to perform such a task. The instructions are simply a guide that indicates a flat surface is required for the "centering boss" to engage with. If you already own a piece of Kadee rolling stock it would, it stands to reason, be designed to accept a Kadee truck. This shows the centering boss if it were to be installed without the truck so you can see the indexed points at 90° intervals that engage the mating points on the carbody. Kadee_centering-boss by Edmund, on Flickr I hope that helps, Ed
gmpullman richhotrain Three? Or four? FOUR
richhotrain
Three? Or four?
ATLANTIC CENTRAL As the owner and operator of about 800 pair of Kadee trucks, I will go out on a limb here and suggest that I am qualified....... At least a third of my Kadee trucks are the self centering type. Rich, the self centering truck, as you have likely seen by now, has a bushing that the truck pivots on. The hole in the truck bolster that receives the bushing has V shaped recesses on each side. The bushing has matching V shaped protrusions on each side. For the initial installation of the bushing, it does not need to be perferctly positioned, it simply needs to fall down into the little V in the bolster. Then install the screw, most of the way, but not fully tight. Hold the truck in a straight position as if the car was on straight track, pull the truck away from the car, this will engage the V of the truck bolster with the V of the bushing. Holding the truck in this position, tighten the screw. Flip the car over and let the trucks hang free, the should be in a straight line with the car body. If not, loosen the screw very slightly, and turn the truck as far as it will go in the direction necessary for the adjustment until the bushing turns slightly, Retighten and recheck. When the car is sitting on the rails, the little V notches do nothing, they only engage when the car is lifted to "center" the trucks, in theory making it easier to place it on the rails. The self centering feature itself is of marginal value in my mind, but, the fit of the bushing in the bolster is much better than just a screw, or even the bolster flange on the "average" freight car. The self centering feature works the same on both sprung metal, and HGC equalized versions of Kadee trucks. Questions are welcome, pictures may be possible if needed. Sheldon
Ed, thanks for the great photos.
I convert most of my freight cars to Kadee trucks that have been refitted with Intermountain wheelsets and I have been using mainly the self centering ones for a while now.
But I only have a handful of Kadee cars and have had little reason to take them apart to notice or remember the little nubs.
They will make the assembly process even easier.
ATLANTIC CENTRALBut I only have a handful of Kadee cars and have had little reason to take them apart
Off the top of my head I probably have three-dozen Kadee cars. Likewise, I don't recall ever having a need to disassemble them.
On some of the cars that I've retrofitted self-centering trucks I have passed a mill file over the existing body bolster which provides a flat surface for the centering device to rest on. I noticed the four gaps in the soft-wood bolster of the caboose where the boss was contacting it. That gave me a clue that the centering boss must have some kind of indexing tabs.
As seen in the lower-left of this photo:
NYC_19186_truck by Edmund, on Flickr
Sometimes, when tightening the screw I've noticed the centering boss wants to twist in the clockwiise direction even while lifting the (upside down) truck. I simply counter-rotate the truck which holds the two triangle-shaped bosses perpendicular to the car centerline then give the final "snug" to the screw.
There used to be a column in M-R, was it called "Kinks" where some of the things — like fitting trucks to cars — were addressed. Some of there tricks were pointed out there.
Regards, Ed
gmpullman ATLANTIC CENTRAL But I only have a handful of Kadee cars and have had little reason to take them apart Off the top of my head I probably have three-dozen Kadee cars. Likewise, I don't recall ever having a need to disassemble them. On some of the cars that I've retrofitted self-centering trucks I have passed a mill file over the existing body bolster which provides a flat surface for the centering device to rest on. I noticed the four gaps in the soft-wood bolster of the caboose where the boss was contacting it. That gave me a clue that the centering boss must have some kind of indexing tabs. As seen in the lower-left of this photo: NYC_19186_truck by Edmund, on Flickr Sometimes, when tightening the screw I've noticed the centering boss wants to twist in the clockwiise direction even while lifting the (upside down) truck. I simply counter-rotate the truck which holds the two triangle-shaped bosses perpendicular to the car centerline then give the final "snug" to the screw. There used to be a column in M-R, was it called "Kinks" where some of the things — like fitting trucks to cars — were addressed. Some of there tricks were pointed out there. Regards, Ed
ATLANTIC CENTRAL But I only have a handful of Kadee cars and have had little reason to take them apart
Yes, I tried to explain that adjustment procedure above, not sure if I was clear enough.
Like I said, I prefer sprung or equalized trucks, and I repalce most rigid trucks, even on brand new quipment in many cases.
I just installed the two new trucks on the Kadee covered hopper.
After a restless night of tossing and turning over the complex terminology and Kadee's instructions how to apply that terminology, I threw my hands up in the air and just went for it.
Before doing so, however, I turned another Kadee covered hopper upside down and observed that the center bushing stayed in place, perpendicular to the underside bolster, no matter how I rotated the truck. Awesome!
So, I pulled off the factory supplied mounting tab and screwed down the truck assembly. At that point, I noticed that the center bushing was not staying in place. Why not? Because the new screw supplied by Kadee was too long.
So, I took off the Kadee supplied screw and use the shorter screw that was originally on the car. The covered hopper now works like a charm, and the car rolls very, very smoothly down the track.
I have nothing more to say. Thanks to all for your help and advice.
gmpullman ATLANTIC CENTRAL But I only have a handful of Kadee cars and have had little reason to take them apart Off the top of my head I probably have three-dozen Kadee cars. Likewise, I don't recall ever having a need to disassemble them.
In retrospect, I never should have removed the truck. Rather, I should have tried to clean the wheels with the truck still attached to the underside of the car.
Actually I initially tried that, but it was proving difficult to thoroughly clean the wheels, and that is what prompted me to remove the truck and take off the wheelsets.
I guess that the issue is whether I am replacing Kadee trucks on Kadee cars with replacement Kadee trucks. If I am buying Kadee trucks to replace non-Kadee trucks on non-Kadee cars, that is a whole other matter. I assume that is the reason that Kadee includes the following instructions - - for installation of Kadee trucks on non-Kadee cars.
Lastspikemike This thread is very illuminating. The more I think about this the better I appreciate the plastic Kadee trucks. There is no need to be concerned about the trucks "falling apart" because they are simple to reassemble. Fiddly but not difficult. Certainly less fiddly than fitting coupler springs, just for example. But the best feature seems to be the prototypical aspect. Because the truck mounting screw only affixes the center bushing the freedom of the truck itself to rotate and rock is not affected by mounting pressures. That freedom is as designed in by Kadee and is a fixed quality. The car rides on a Kadee truck more or less by its own weight just as in real life trains. The difference is when the car derails the trucks don't fall off, or rather the car doesn't fall off its trucks. The older metal trucks don't have this added feature but are really sprung unlike the plastic versions. I'm beginning to like Kadee trucks.
This thread is very illuminating.
The more I think about this the better I appreciate the plastic Kadee trucks.
There is no need to be concerned about the trucks "falling apart" because they are simple to reassemble. Fiddly but not difficult. Certainly less fiddly than fitting coupler springs, just for example.
But the best feature seems to be the prototypical aspect. Because the truck mounting screw only affixes the center bushing the freedom of the truck itself to rotate and rock is not affected by mounting pressures. That freedom is as designed in by Kadee and is a fixed quality. The car rides on a Kadee truck more or less by its own weight just as in real life trains. The difference is when the car derails the trucks don't fall off, or rather the car doesn't fall off its trucks. The older metal trucks don't have this added feature but are really sprung unlike the plastic versions.
I'm beginning to like Kadee trucks.
That's why Kevin and I put them on everything, they are better,
ATLANTIC CENTRAL That's why Kevin and I put them on everything, they are better,
richhotrain ATLANTIC CENTRAL That's why Kevin and I put them on everything, they are better, For me, I guess that time will tell if the Kadee trucks are better. But, in the meantime, let me ask, is it the center bushing that makes it better? Rich
For me, I guess that time will tell if the Kadee trucks are better. But, in the meantime, let me ask, is it the center bushing that makes it better?
Rich, the most important feature is equalization, flexing to keep all four wheels on the rail at the same time.
The bushing is a bonus, and I install Intermountain wheelsets to make them more free rolling.
ATLANTIC CENTRAL richhotrain ATLANTIC CENTRAL That's why Kevin and I put them on everything, they are better, For me, I guess that time will tell if the Kadee trucks are better. But, in the meantime, let me ask, is it the center bushing that makes it better? Rich Rich, the most important feature is equalization, flexing to keep all four wheels on the rail at the same time. The bushing is a bonus, and I install Intermountain wheelsets to make them more free rolling. Sheldon
Lastspikemike The Kadee trucks flex enough to allow you to take out and install wheelsets without removing the truck from the car. This applies to both metal and HGC plastic trucks.
The Kadee trucks flex enough to allow you to take out and install wheelsets without removing the truck from the car. This applies to both metal and HGC plastic trucks.
Living the dream.