Large Scale Central

Bachmann Handcar & Motor

Modeling Motive Power
#1

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This is the motor from a Christmas Gandy Dancer with 2 trailers. I have 4 of them in pieces, and most have cracked gears and broken studs for screws. I did find one chassis with ‘good’ gears.

Now I need to find a good motor! One smokes as it spins from the commutator, and the other one (pictured) spins but the brushes get very hot.
Am I right in thinking that things get hot when they have electrical resistance?

I think I am going to have to take the brushes out and clean everything. Unless someone has a better idea?

#2

Your resistance = heat idea seems good. Personally, I cringe in thinking about taking that apart, but I’m sure you’re vastly better in putting such things back together then I. Before that effort though, perhaps spraying with Deoxit might give some remedy?

#3

I and the kids always loved the Christmas Gandy but they always failed. I gave up after getting several. And yes the screw post always failed. But not parts available to fix that and seems was a failure point on all of them. Gears and screw posts. I’m sure it was cheap plastics which Bachman had on several items.

#4

Pete,
If you do go so far as to take the whole thing apart, could a new housing be 3D printed? That would solve some of your broken/cracked issues, if I understand correctly.

1 Like
#5

I have been taking electric motors apart since I started re-winding Mabuchi and MRRC/Triang motors in the 1960s when I took up slotcar racing. So no cringe-ing!

Good idea John, but as I have 4 of these beasts, I’m sure one will be usable!

Indeed. But I do have 1 set of good gears, and Jiro has replacements if I need them.

#6

I got a few minutes today to work on the motors. If you look at that first pic I posted, you will note one of the brushes is angled - probably melted the end cap from the heat.
Another one has a wire soldered to the brush holder instead of the tab under the holder top, so it may have melted something.

I pulled out the angled brush holder and the one soldered to. Managed to drop one brush on the floor, and when I pushed a brush in to the holder it stuck and had to be removed in bits with a pin. Sigh.

I ended up with what I think are a good pair. I applied power and it spun and faltered a bit. Giving it power produced lots of glowing around the commutator - not good.
I took the pin and cleaned out all the slots. Now I have occasional fireworks from one brush, glowing dust at the front near the bearing, and a spark jumping from one brush to the other over the commutator while it is spinning.
It did work properly for a couple of seconds - sounded really powerful.

I clearly need to clean the whole front end and polish the commutator.

#7

I agree on the commutator and clean the crap out of the grooves. I saw that melted angled brush holder on neutral side but I think of you clean up the commutator and maybe file a little angle on the brush 5 or 10 degrees for a bit more contact then it’s probably gonna work well.

Just my thoughts

If not, you can always just do what the automotive manufacturer does and say you need a new motor.
Oh, geeze we are sorry that motor has been discontinued and no longer available. Now could we direct you to the new car section? If they say no then that’s usually what makes my phone ring !

#8

As it happens, I have 2 or 3 motors, and between them I got one working. With the commutator cleaned, it started to sound like it was working.

Unfortunately [if the video posted] you can see the rocker arm didn’t move. Sigh. The small gear that drives it was indeed split. One of the worm gears is split, but the other is still hanging on.
I tried an experiment with my soldering iron. I’ll let you know if it works.

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Finally - I have a green version with a different bottom plate, and split gears. It does have pickups on the trailing cart. Wonder why the white ones don’t.

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#9

It didn’t. Cracked again trying to get it on the axle, despite my using a reamer to clean up the hole!

Jerry mentioned someone told him that fishing line and ACC could be used. I dutifully drilled a couple of holes after I found the thinnest line in my box.

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The red clamp is holding the crack tightly closed, I am going to leave it 24 hrs before trying to install it.

#10

Wow Peter, great idea.

The more I read the more I’m starting to think that Bachman hired some of the best draughtsmen to design the shells and some of the best turnaround specialists to design the innards, making them the best producers of static locomotive displays in the model railway industry.

Looking forward to seeing if you can get the beast to move.

#11

I installed the 2 ‘wired’ gears this afternoon.

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The small one on the left, which drives the rocking Santa+Elf appears to have gone on to the axle without issue. The right hand (large) one, which is driven by the motor worm, looks to have tried to split. In addition, the axle center tube has split. You can’t win.

The worm gear is tight on the axle, as is the small gear driving the action. However, the right side wheel/axle has to be firmly connected to the left wheel/axle for this thing to crank the handle.
In addition, the acc and line is knocking against the black plastic that retains all the motion gears. I moved it but I may have to file down the line+acc.

I poured a bunch of Gorilla glue into the split on the axle and into the axle hole at the left, with the hope that it will provide a little friction.

It’s worth noting that it ran (see video above) with only the gear on the other axle tight, and maybe without the wheel/axle on the other side from the gear.
Track test tomorrow, hopefully.

#12

fishing line
a new idea for me.
how do you fasten/tighten the line?

do you think, it could be worth it, to try that on a first generation Bumblebee/Big Hauler?

#13

That is what you wrap with fishing line and CA.

#14

This morning’s track test. I didn’t expect success, but note that the Elf rises as Santa leans forward.

I used the red clip to force the gear back to shape, (see photo above) then tightened the line and liberally squeezed acc over it. Then leave it to set for a long time.

The issue with a Big Hauler is that it only has 1 gear, so the replacement cost from Jiro is only about $30+/-. This handcar has 3 split gears, costing $58 to replace!
But no reason you shouldn’t try the fishing line and acc method.

#15

This mechanism is going to cost more than the box of parts that I bought. :roll_eyes:

#16

thanks.
so about $50 or more with transport and tariff.
in that case i think, it can not hurt, to try repairing first.

#17

After reading all these Bachman repair threads, I must say that at the cost of these trains and the minimal difference between plastic, Delrin and metal gear boxes, I’ll sadly be avoiding Bachman despite their above average appearance.

#18

Depends on what you want Bill. I wouldn’t rule them out and I don’t even like modeling that era. If you want solid out of the box then you pay for it up front! However A LOT of their stuff is highly workable IMO.

Remember this is coming from a :rooster: so you make your own decision.

#19

I agree with Rooster, and to Bachman’s credit, they have been listening to consumers and correcting problems with every new release. The C-19 is probably the crown jewel of their Fn3 line. It runs perfectly and doesn’t suffer from many of the earlier design problems. That’s probably why used ones are selling for as much or more than new ones did!

The older and especially the cheaper products like the one Pete is attempting to restore did in fact have a lot of problems, but even still there are plenty of first generation Big Haulers that are still operating.

#20

Nope. My $30 included shipping. Jiro uses a flat rate envelope and charges $13. His gears cost $15 - $25 depending on complexity.