Large Scale Central

Aristocraft BNSF Dash 9 Motor Failure

General Discussion
#21

I’ve only seen a few of the plastic drives, and they usually did not take long to destruct. Before that, they were quieter. Also I think the metal drives came at the same time or shortly after they started soldering the motors in.

Interesting history, the original design was ok, but the movement of the motors from forwards to reverse spread the “forks” that made the contact with the brush “tabs”… That caused power conduction problems. OK, now solder them to avoid that problem. Oops, now that the motor cannot self-align in the block, the misalignment causes the plastic drives (that kept them quiet) to get chewed up… ok go to metal hex drives…

Now, when you get one, you need to listen for noise, and if so, you have to re-heat the soldered forks to realign the motor to minimize the noise… and the stupid rubber pads… oh, that’s another story.

Greg

#22

Wow!
What ever happened to good engineering?

#23

There’s tons of stories like this, usually motivated by trying to save money in manufacture, or misguided engineering “ideas”.

I’ve been in the hobby a while… paid attention, and investigate stuff, surrounded myself with friends of equally inquisitive nature, etc.

Greg

#24

If anyone wants to see the two drives go here about half way down this is on a sd45 but the same George gives a time when the brass came out

http://www.girr.org/girr/tips/tips8/sd45_tips.html

Richard

#25

Greg Elmassian said:

There’s tons of stories like this, usually motivated by trying to save money in manufacture, or misguided engineering “ideas”.

I’ve been in the hobby a while… paid attention, and investigate stuff, surrounded myself with friends of equally inquisitive nature, etc.

Greg

Yea. It seams that each new group of designers needs to prove to themselves that the failed designs of the previous group of designers do in deed not work.

#26

Richard,
Thanks for the SD45 tips, it was real informative.
Ken

#27

Greg,
I am going to try to get in touch with the motor manufacturer you suggested and send them photos to see if we have a match and let you know what I find out.
In the meantime I will try the motor I am being sent from Gary with the plastic hex ends out of the old SD45 after I replace that hex end with the brass from the current bad motor.
Thanks! Ken

#28

Ken,

I have a couple old SD45 1st run motor blocks. The motors have the brass fitting. They originally had plastic but Aristo at the time offered free brass replacements because of the failures. Let me know if what you get doesn’t work. I can get you one of the old ones.

#29

Appreciate it Paul,
I will definitely let you and everyone else know if the others work or not.
The other motors seem to be running ok but I will know more once I install the one being sent. That is if we can get the hex heads off and on. Never removed hex heads before so I’m not sure just how difficult it is or how to do it. As mentioned before I may have to send them over to Barry to have him remove/replace them.
Thanks for the offer and we’ll let you know.
Ken

#30

If you don’t have a puller with a small diameter pin, I would not try it… They are on there tight.

If I had to remove them, and did not have a puller, I would support the back side of the hex, blast the hex part with a small torch and drive it out with a nail setting punch (the kind you use to recess finish nails in wood below the surface).

BUT

Putting them back on might be an issue… if you try to press them on, and the motor shaft is not one continuous piece of steel, but 2 parts, you drive the half shaft into the motor and really mess things up… do not ask me how I know, but it is upsetting.

In other words… send to Barry. He is a machinist.

Greg

#31

Good advice.

#32

By the way, there was an earlier suggestion that you could just run a block with one motor.

If so, you need a hex shaft to run to the “end” axle that would be “orphaned” with no motor.

Alternatively you could open the “orphaned” gearbox, and remove the worm from the gearbox.

It’s a solution.

By the way, I forgot if this was mentioned, were your motors soldered in place?

Greg

#33

Greg,
None of the motors in any of my Dash 9’S (except the CP Rail listed below) or SD45’s are soldered in currently, however this BNSF was originally.
It was pulling 2 1/4 amps and making tremendous noise in the front truck. (3x what was normal for a noisy Dash 9) I then unsoldered the motors and the noise was still that of 3 original noisy motor blocks but the amperage draw went to less than 1.
Later when I removed this motor you could see the bend in the shaft but I couldn’t help it in any way.
I did try another motor out of another unit (as mentioned above) to which I was applying grease and it ran perfect with almost no noise or amperage.
I of course can’t use that motor. All the Dash 9’s and SD45 have run flawlessly for years without soldered motors, just a little noisy.
Don’t know if soldering the motors in is better or worse for these drives but they seem to draw less amperage and run smoother when they aren’t soldered.??
Gary is sending the SD45 motors and I called Barry again and I will send them to Barry as you suggested and he’ll Change out the hex heads.
So thanks to both of you for your advice and we’ll let all of you know how it turns out.
If the SD45 motors run at the same rpm and amperage, we should be ok.
Hoping for the best!!!
PS Thanks Gary!
Thanks to all of you also.
Ken

By the way, about that Canadian Pacific Dash 9 (newer version) that has not been unsoldered, it runs quiet as a mouse and with low amperage. Should I leave it alone or for drive safety and longevity, unsolder it also??

#34

So, Aristo started soldering the motors in years ago, therefore the rest of your Dash 9’s are pretty darn old. They might have the plastic hex drive on the motors.

I have a funny story about this. Years back, when we discovered these issues, we complained, and one of the “Aristo Faithful” reported he never had these issues, we were baffled, since even though this guy was “drinking the Kool Aid”, he was an honest guy.

After asking him dozens of questions, it turned out that as soon as he got his new 3 axle loco, he IMMEDIATELY unsoldered the motors to allow them to flex and self-align as was intended in the original design. It was pretty funny and took about a week as I recall.

So, unsoldering the motors will allow the motors to align with the gearboxes and almost always results in smoother running and quieter… and as you mentioned, this will reduce current draw in most cases.

The negative is that now the motors can move a bit, they will rotate a little bit when switching directions. After a while the contact between the motor brush tabs and the “forks” that engage them will worsen, and most people experience jerkyness as power gets interrupted with the motion of the motors and just running.

So the best solution seems to be realigning the motors IF they are not aligned well, and all you can do is re-melt the solder while pressing on the motor. I have had good success with this.

The ultimate solution would be to solder flexible wires to the motor, and then solder them into the motor block somewhere so the motion would not affect power conduction and the motors could self align.

Greg

p.s. do NOT resolder or unsolder a loco running well… it WILL get worse!

#35

Thanks Greg,
This all makes good sense since most of my units run well due to unsoldered connections.
I always wondered if the motors were moving in the block.
Maybe if you use momentum on the power pack it will limit sudden
movement of the motors and increase longevity.
We try to make our equipment last as long as possible for our program plus I really like the Dash 9’s and SD45’s.
We do tend to run our equipment more than average and that is why we put grease/lubrication holes in our gearboxes which is the best thing we’ve ever done. Haven’t had a breakdown in a long time as a result.
I am not sure of the age of the Canadian Pacific locomotive but it was in a yellow box. It is literally the quietest running unit in my entire fleet.

Ken

#36

When I need to remove the brass gear from a motor shaft, I use a small torch and heat the gear and then it just falls off on all the LGB motors I did this to.

I put the gear on the new motor the same way, heat the gear and just push the shaft into the gear.

#37

Note:

If you use Dan’s suggestion above I suggest you use a good heat sink between the brass and the motor. I’d bag the motor and then use wet paper towels wrapped around the shaft next to the motor. It doesn’t take an over kill, if you heat and remove quickly. I’d also suggest needle nose pliers on the brass as they will act as a sink too. I use to have one pair o pliers dedicated to heat work as they would bend easily until I tempered them again.

For what it’s worth, lately not much…

#38

John, Dan,
I think doing that may be a liiiitle beyond me. Besides I don’t have a torch.
I probably better send it over to Barry. He’s done this a few times.
Good advice though for those who are braver and more skilled than I.
Many thanks!
Ken

#39

I’d be a little worried about recommending the heat method to someone who does not have experience with a torch.

I have a small pencil point bernz-a-matic and use it to heat the screws on the aristo steamer and diesel wheels when they are slathered in red loctite. If you don’t do this with Aristo, you often twist the head right off the screw or round out the Philips head. (Translation: you are screwed).

With a nice small pencil point, you could heat the brass quickly and not the shaft and pull it off, but I guess I would use a pair of vise grip pliers on the shaft for a dual purpose, a heat sink, and a base to lever the hex drive off, i.e. put a pair of needle nose pliers between the vise grips and the hex drive, this gives you something to push against.

Heating the hex drive might anneal it a bit too, might be worth quenching it a bit after heating and reinstalling, but I’ll defer to John about this, since the goal is to toughen it, not temper it like a cutting edge or tool.

But since you don’t have a torch (but a good tool to have), sounds like off to Barry.

Greg

#40

The idea is the same as changing a steamer’s rims, heat them so they expand and there is no force needed as the hole gets bigger too. I don’t see a need to get as hot as annealing. That would have been bad for loco tires if they got soft! It’s more like the sun stretching our rails, too hot to hold comfortably, hence the pliers…

The heat sink is to protect the winding’s shellac or what ever is used now. Greg mentioned a split shaft… protect at all costs.

John, I have no side and I’m not taking hostages. (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-innocent.gif)