New Run of Athearn Challengers, Surprise!

[Cajonpassfan]

Well, it turns out replacement traction tires are available from Athearn, $6 a pair, not bad. Commendable.
$10 for shipping and "handling" not so much
Never mind they are replacing a defective part, and I'll have to pull the pins on the main drivers and do a lot of "handling" myself to fix the problem. And I don't know whether the new tires are any better than the loose original ones...
Okay, rant over.
Otto K.

[Cajonpassfan]

Bump!
I’d like to revive this thread, as there is another pertinent discussion of the Challenger TT slippage on a current but generic Weekly Update. Perhaps after over a year, we now have a better understanding of the problem?
@peteski Pete is suggesting that perhaps oil from the mechanism is seeping onto the rear set of TT’s. Has anyone else experienced this situation?
Otto K.

[rgengineoiler]

Just beware for sure!  The Challenger I got and waited for in the last lot, 2015 or 2016 I think was a pile of junk.  All the issues with it are on the Rail Wire titled, " Challenger Good Grief".  After all was done I ended up spending an extra $310.00 to finally have it running right and that took 15 months including shipping to Athearn and Jerry mentioned below.  A New Soundtraxx sound decoder, HO instead of N scale and other wiring issues were fixed.  The interior of the model was an ugly wiring soldered mess from the factory until repaired.  Good Grief was it bad.  With shipping and repairs I ended up with an over priced reliable steamer.  Athearn repair took 7 months and was  junk work plus shipping of course.  Contact jwoodone@cox.net if you have problems.  He saved my Challenger for sure.
Doug     

[propmeup1]

I'm not doing the steam era, but I still couldn't resist ordering one of these beauties because it's NP!. It should be here this week.
Some day I hope to get back to building my layout; just about everyone I know is in a model railroading slump.

The Reading FTs, they N scale ? A & B with sound ?

[delamaize]

Gonna bring back this thread for a bit, Might make a new thread when I get things sorted out.

So, It's pretty much a known thing, The Athearn Challenger is kinda a Lemon. It sucks because it is such a nice looking locomotive.

On to why I dug up this thread. I sent mine back to Athearns to be "fixed." It came back with a different motor, which improved the speed problem, Mine does about 60 SMHP now, I would prefer prototype top speed, but I'll take this over 30 SMPH, which is what mine did originally. Even after the "Repairs" that Athearn did, it still pulled like hot garbage.

So, It went on my work bench.....Off and on for over the last year or more.......

A few days ago, at the Train show, at Washington State History Museum, I did some test running on our club layout (MRNS). First test run was on the NTRAK Mountain line. First test resulted in a drastic improvement. Originally it struggled to pull 25 cars. Now, With my improvements, 40 cars from multiple manufactures. Needless to say, I'm pretty impressed with the improvement. Now, Yesterday, I had some time on the Inner Main. So why not? lets see what it will REALLY do. I started with 40 mixed freight cars, with 30, 40' box cars, Mostly MT, and 7 gondolas, (mostly MT) 3 flat cars, and a caboose. It pulled with no issues. I ran it like this for probably 30 minutes, then I decided to go after it. I started adding 5 more box cars every other lap. So, where is the top? Well that depends on what you call top. With no slippage at all, 50 cars is all it's got. I had 60 on it, But it would slip a lot in the corners. 55 was doable, but it did have some slight slip in the corners.

This is a drastic improvement, but it wasn't with out a LOT of work. so what did I do?

New traction tires, that are taller and slightly wider. This is creating a problem right now as the traction tire groove is not wide enough, so the traction tires are bowed up a little near the outside edge of the wheels, which makes it have a little bit of a bump when it runs. But it's not a big deal. I'm planning on chucking the wheels into a dremel or lathe and making the grooves slightly wider, one of these days.
But wait, Their is more.

I added weight in the boiler, and on top of both of the drive trucks.
Tweaked the lateral gear alignments, and made shims to try to help with gear walk.
re-quartered all the drivers.
Tweaked CV settings
De-lubed, and re-lubed everything
Cut one turn out of the spring on the pilot truck
Removed the spring and screw/pin on the rear truck.
Tweaked, and tuned valve gear
Gauged all the wheels
Adjusted, and tweaked electrical pickups
Rewired everything in the locomotive
Replaced all the wire in the locomotive.

Still to do:
Find places to add more weight
Dremel or lathe out the traction tire groove wider
re-engineer and rebuild the rear truck mount

Oh, I forgot about that, So, the rear truck.....
It is mounted, by a pivot at the front of the truck, attached to the rear of the power truck, then a screw/pin to the bottom of the firebox, with a spring for tension. So, here is the problem, The pivot on the front of the truck is too low, which lifts the front of the truck off the rails. When you push down on the rear truck, to put the front axle on the rail head. It lifts the front of the power truck off the rails by like 1/4". In addition, it only allows for lateral swing, No vertical movement at all. I am working on fixing this right now. I'm hoping this might squeak out a few more cars, some how.

Stay Tuned for more, I will try to make updates as I make changes, and post the results.

It has been a ton of investigation and work to get to this point, IMHO way too much work for a brand new locomotive. But, It is a beautiful looking locomotive, and it does run well, But you'd think  Manufacture would put a little more testing and proving on designs, especially when the prototype was known for pulling 100 loaded boxcars, at 100 MPH across the plains.

[peteski]

Thanks for the detail of your "tuneup" (more like major rebuild). 

Unfortunately I see more and more newly-made  models that after I examine I see lots of room to improve or slightly redesign to make them run and/or look drastically better.  I Also ponder why manufacturers just can't get things "right", where sometimes a very little change is all it takes to make a sub-par or even a decent model be a great model.

As for the traction tire problem, can't you use a better-fitting tire but just shim over the top of the traction tire driver bearings to bring it down slightly, to better contact the rail?  I have probably about 20 different sizes of traction tires (both for American and European models). There might be some which will be a better fit for your model (I just have to dig them out and test-fit them on my Athearn Big-Boy/Challenger models)

[NDave]

Thanks for your detailed post.

I have also had on ongoing struggle with my 2017 issue Challenger. It was back to Athearn 3 times, first to re-gauge all the axles on the loco, then to replace the decoder when the sound died, then to have it's front gear tower replaced. On it's last trip back to Athearn, it was actually sent back to the factory in China for refurbishment, and after a very extended delay, Athearn sent me a replacement loco. But the replacement had many of the issues that I think you faced... it would BARELY pull 8 MT box cars up the 1.7% grade on my layout. Watching very closely as it ran, it was clear that the traction tires were not even making contact with the rails... I could slide a piece of paper between the traction tires and rail heads.

As I was trying to work thru and solve this issue with Athearn, I researched replacement traction tires (Athearn seems to have picked an odd width for its tires), considered adding a layer of Bullfrog snot, and other remedies. Finally, I was informed that my original loco had just returned from China (this was >5 months after I had sent it to them), and would I like to have IT back. They actually sent my original back while I still had the replacement, and I A/B'd the two locos. My original pulled (and pulls) 21 MT freights up the grades on my layout. I don't know what it would do on a flat, because I don't have a flat stretch of track long enough... so I kept the original, and sent the replacement back.

It ran great for about 8 months, and then started exhibiting periods of excessive current draw and slow down, as if the gears were binding again. To cut to the chase, it wasn't the gears... it was the motor brushes. They had worn so much and spread so much graphite dust around the interior of the loco and motor, that the motor was shorting internally. By this time, It was out of warranty, and I wasn't going to send it back to Athearn a 4th time, so I ordered a replacement motor (from Athearn) and decided to attempt the repair myself. Turns out that replacing the motor is fairly easy, as it does NOT require removing or disassembling the gear towers. You do have to unsolder the PC board to move it out of the way, and uncouple the universal joints. The worst part was getting over the fear of destroying a $300 loco. I posted a "how to" on another forum, and can re-post that on TB at some point (I was told that posting a link to another forum is frowned upon).

I still have not figured out how to remove the gear boxes for clean & re-lube... what's the secret? I am hoping you don't have to separate the two halves of the chassis...

I made two other small tweaks to my challenger:

First, the trailing truck "spring" (a bowed metal thingy) was interfering with the underside of the loco cab/frame (plastic), resulting in occasional derailments while backing thru turnouts. I considered removing the spring altogether as per delamaize, but was worried about affecting the tracking of the truck. So, I chose to use a scalpel to slightly shave the underside of the loco cab/frame where the interference was. Seems to have solved the problem.

Second, when running at road speeds around curves, I was hearing noises indicating that the rods and valve gear were hitting each other. Although I didn't see evidence of binding, I was worried about the long term consequences (loosening rod pins, or drivers out of quarter). After a lot of observation, I decided that the interference resulted from too much lateral play in the drivers, much more than I though was needed to negotiate my 16" min radius. So, I shimmed the outer edges of the bottom plates to reduce lateral movement.



The shims are strip styrene (actually, HO scale 1 x 3 from Evergreen) superglued to the sides of the bottom plates. Since the glue does not stick very well to the cover plates (but well enough), it's actually fairly easy to remove the shims if necessary. Shimming took care of the interference I was hearing. While I am sure the shims have an effect on the min radius the loco can handle, I have seen no apparent effect on the locos ability to negotiate the 16-17" radius curves or turnouts on my layout (incl some Atlas C55 #5s and #2.5Ys leading to my engine yard). You will notice that the front tower only has the forward axle shimmed... while the rear has all three. It may only be the forward axle that needs shimming... It's also likely that shimming all axles would have a greater effect on the min radius.

[I also shimmed the drivers on my two Bachmann 4-6-0s. On one, I heard the rods hitting the valve gear, but could not see any binds. On the other, the rod hitting the back side of the valve gear actually caused the loco to shudder. The full thickness of styrene was a bit too thick for the 4-6-0s, tho' so I used a razor blade to scrape the styrene strip down to about 0.15mm thick before I cut it to length and glued  it to the cover plate. Again, shimming seemed to have solved the problem, w/o affecting the ability of the locos to negotiate my curves and turnouts.]

Since the motor replacement earlier this month, my challenger has been running great (knock on wood). It easily pulls 20 cars around my layout, negotiating ~1.7% grades on ~16" radius curves, and can handle 21-22 cars with just a little wheel slip. That's good enough for me. The next major change will be replacing the 1st gen Tsunami decoder with a Tsunami 2 Steam 2 decoder...

[delamaize]

Update: Yesterday, The challenger ran for 2.5 hours, pulling 40 Assorted Ice reefers + caboose with no issues, and still had some left. I made a few notes, and will be making a few more improvements.

[conrad]

Gonna bring back this thread for a bit, Might make a new thread when I get things sorted out.


Rewired everything in the locomotive
Replaced all the wire in the locomotive.

Just found this post.  I am just getting ready to replace the burnt out incandescent lamp in my circa 2007 challenger (w/ replacement TSU 4664N decoder).
If you actually replaced the wires from the headlight to the boiler PC board I'd appreciate any hints on how you did it.  Looks like a fearsome project.

Conrad

[NDave]

Conrad,
I have not (yet) replaced the light in my  2017 release challenger, or re-wired the headlight. But, it is on the list of things to do... mostly because the light on mine is orange, which doesn't look right for a headlight.  I plan on replacing the 1st gen Tsunami decoder in my challenger with a Tsunami 2 steam 2 decoder later this spring, and figured I would look at replacing the headlight when I did that. I did a net search, and couldn't find much, except a how to for the HO genesis challenger. IIRC, replacing the light on the larger model required removing the headlight housing, and then the shield for the air pump. Looking at the exploded drawing of the N scale challenger, it looked like the headlight housing should just lift off... and I was hoping that I would be able to pull the light out (don't know if it is incandescent or LED) and replace it with a small warm white SMD LED. If you figure it out, please share what you find...

I am also thinking of upgrading the motor to something coreless... the open frame motor Athearn used is pretty noisy, and detracts from the sound experience. I have an idea of what coreless motor I might be able to adapt, and it looks like it might be pretty simple. But Id need to get a gear puller in addition to the motor, and that adds to the "activation energy" required...
Dave

[peteski]

Conrad,


I am also thinking of upgrading the motor to something coreless... the open frame motor Athearn used is pretty noisy, and detracts from the sound experience. I have an idea of what coreless motor I might be able to adapt, and it looks like it might be pretty simple. But Id need to get a gear puller in addition to the motor, and that adds to the "activation energy" required...
Dave

I doubt that the motor itself is the main source of noise. Unless the rotor is way out of balance, and causing major vibrations.  Usually the rest of the drive train generates most of the noise.

[NDave]

I doubt that the motor itself is the main source of noise. Unless the rotor is way out of balance, and causing major vibrations.  Usually the rest of the drive train generates most of the noise.

Certainly thought of that... but I did run the motor outside the loco, and it is DEFINATELY noisier than the coreless motors in my other steamers. Another reason I'm thinking of swapping to coreless... Tho' I don't really know anything about motor properties, I am wondering if the open frame (cored) motor will not be as responsive (as a coreless) to the B-EMF control of exhaust effects that is one of the neat features of the Tsunami 2decoders.

The motor swap is on a "wait and see" hold until after I swap the decoder, which is at least a month away...

[mmagliaro]

In my totally unprofessional opinion...

Coreless motors are wonderful things, but quietness and responsiveness to BEMF controllers are not on my list of reasons for using them.  The two top reasons I like to use them:

The top three reasons... ha ha ! 

a) Much more power than a conventional motor for the same size

b) Much more usable power at very low RPM, allowing them to move a geartrain at lower speeds than a conventional motor, without giving up any top-end.  Coreless motors can do 100 to 30,000 RPM with useful power in that whole range.

c) There are wonderful planetary gearheads available for them, which give you in-line speed reduction for a huge power boost and a nice slow-down for rocket-sled engines.

They have disadvantages:
They are sometimes not as easy to mount as a conventional motor
They often have weird, short output shafts, requiring sleeving to mount a worm

(They used to be ultra-expensive and prone to destruction from power packs, but both of those problems have been solved by the surplus market and modern power supplies, respectively)

So unless you are after (a), (b), or (c), I would not swap out a motor for a coreless.

[peteski]

I'm not sure about Tsunami decoders, but in general many decoders do not handle coreless motors very well.  I suspect it is because coreless motors have BEMF profile and current consumption very different from conventional motors. So, you might run into a problem getting chuffs and other effects in sync with the coreless motor.

[NDave]

I'm not sure about Tsunami decoders, but in general many decoders do not handle coreless motors very well.  I suspect it is because coreless motors have BEMF profile and current consumption very different from conventional motors. So, you might run into a problem getting chuffs and other effects in sync with the coreless motor.

I've installed Tsunami 2 Steam 2 decoders into three locos so far, all with coreless motors: a Bachmann 4-6-0 with a Bachmann Spectrum short USRA tender using an 8 x 12mm sugar cube speaker, a Bachmann 2-8-0 with a MP Vanderbilt tender using a 11 x 15mm sugar cube, and most recently replacing the Loksound decoder of my Kato FEF-3 with a Tsunami 2 and 13 x 18mm sugar cube. All have coreless motors, and the Tsunamis work great and sound great in them.