Bachmann Spectrum split gears?


jasonelki

jasonelki

Milwaukee Roader
I have never run across a loco with split gears, so I'm not sure if this qualifies or not. Just bought a bachmann spectrum 44 tonner and it runs a little rough, and I'm not sure if it is hesitating when the gear runs over the split area.
The photos aren't the best, but I think it is easy enough to see a split the whole length of the plastic part of the axle. From what I can see both sides look the same, so they are either both split, or thats how these engines came?

Any ideas?
Thanks, Jason
 
Last edited by a moderator:
I don't think any engine has ever come with split plastic gears.....with that split, there's virtually no way the gear can hold onto the axle. My guess is the hesitation is caused not by the split, but by the gear slipping under load on the axle. At some point (as you add cars/load) the engine will just sit there. On the plus side, you can send the engine back to Bachmann for repair.
 
Thanks, I thought this looked odd but the gears on both ends looked the same so I figured I'd ask!


MRLdave said:
On the plus side, you can send the engine back to Bachmann for repair.
Click to expand...

Or not...just received in the mail today, bought it on ebay from a seller with "no returns"! Uhg. Wonder how much the replacement gears are, assuming they are available, as I'll have to "bargain" with the seller on a bit of a refund. That and not sure how this little beast comes apart, this is the first bachmann I've owned in many years.

Had some bad luck on ebay lately, not sure what is going on, but most of the stuff is in some sort of disrepair, which wouldn't be a big deal if it was advertised as such. This great condition new in box stuff is getting old!:(
 
I may be mistaken but I believe you can send it directly to Bachmann and they will repair or replace it for a small fee, like 10 or 15 dollars.
 
RGSfan said:
I may be mistaken but I believe you can send it directly to Bachmann and they will repair or replace it for a small fee, like 10 or 15 dollars.
Click to expand...

Looked into it already, spectrums cost $25, about as much as I paid for this!!
If parts are available I think I'll try and screw it up more, err, fix it myself! :)

I guess tis true, you get what you pay for...
 
Anyone know if parts are available to fix the cracked gears? If so, is it a fairly straightforward correction, similar to an athearn BB?

thanks, jas
 
There is another thread that discusses this problem in great detail. I just can't remember if it is on this forum or a different one.

I do remember that someone posted that Athearn BB gears are a perfect fit and are a better plastic. I can't say for sure because I've never repaired this particular problem.
 
Since everyones design seems to be a copy of Athearn's gear train, the problem will persist. The design flaw is pressing a poorly-sized hollow gear over a slick shiny metal shaft. To prevent slipage, the hole for the shaft is molded undersized. At first-install that's OK. But with time all Nylon (Delrin is worse!) materials will shrink and the stress will exceed the strength of the plastic part - and POP!

Reaming older (aged) parts will help. There's a wealth of busted up Blue Box locos out there with aged gears. They can be reamed ( and cut to correct length) to better match the axle diameter.

But then the shafts need some attention to prevent slippage. A few twists with crocus cloth might help - just on the inboard half. A sticky glue placed inside the gear's bore would help too.

The Woodland Scenics "Scenic Accent Glue" is nice and tacky and compatible with metal and Plastic. I use it like a modeler's "Locktite". A dot with a toothpick is all that is needed. I use this stuff to keep truck and coupler screws from backing out. It won't hold up to a screwdriver but it resists vibration very well.

BTW - I have some 1970s brass diesels with splined axles and plastic axle gears pressed onto the splines. Gee, they have cracked too. :mad: Maybe we need to go back to the old Athearn "Hi-F" drive with easily replaced rubber bands. :D
 
Charles Smiley said:
BTW - I have some 1970s brass diesels with splined axles and plastic axle gears pressed onto the splines. Gee, they have cracked too. :mad: Maybe we need to go back to the old Athearn "Hi-F" drive with easily replaced rubber bands. :D
Click to expand...

Those are an easy fix. Northwest Short Line has replacement gear kits made of brass. They're available for 4 and 6 axle locomotives as axle sets and tower gear sets as well as replacement worm gears. They have them for KMT and the other popular brass diesel drives. The only other thing you'll need is a NWSL gear puller to remove and replace a wheel and install the new brass gears. I've been using the NWSL sets on my brass diesels for 20 years and will say they are worth the time and money.
 
From the parts diagram it appears the wheels pull apart and the axle should slide out, similar to certain athearns. I'm hoping not to have to pull the engine apart too much, anyone fix one of these before?

Hoping the gear parts are easy to come by, will find out Monday when customer service is open.
 
I've had those NWSL gears on order at my LHS for 6 months now. It seems like NWSL is "asleep" according to the LHS guys. Some replacement wheel sets I bought from NWSL were improperly made and had to be returned.

My latest tactic is milling down LifeLike frames to repower the brass diesels. It works great! DCC attachment posts on the weight and better motors with flywheels are a big upgrade. If the gears on the new trucks crack, I'll just change 'em as a periodic thing like tires on a car.
 
I believe I read on another forum a guy was in the very same position you are...Bought on eBay, cracked gears, no warranty card, etc, etc...He called B'mann, they said to send the engine back...Got a brand new one in return...!!! You might want to try this.
 
Steamfreak said:
I believe I read on another forum a guy was in the very same position you are...Bought on eBay, cracked gears, no warranty card, etc, etc...He called B'mann, they said to send the engine back...Got a brand new one in return...!!! You might want to try this.
Click to expand...

Hmm, for sure I'll give that a try, need to call them anyway to find parts, might as well ask!!
Thanks
 
Charles Smiley said:
I've had those NWSL gears on order at my LHS for 6 months now. It seems like NWSL is "asleep" according to the LHS guys. Some replacement wheel sets I bought from NWSL were improperly made and had to be returned.
Click to expand...

I too am waiting on an order from my LHS from NWSL(at least a month). Is it the same item?

NWSL Blunt Axel Nickel Silver Wheelsets 53-371404
 
"NWSL Blunt Axel Nickel Silver Wheelsets 53-371404"?

I'm not sure. They were either for a Athearn SW or a SD9. It's been too long. Both have since had LifeLike chassis substituted to power the Athearn detailed BB shells. I'm kind of glad it all turned out that way frankly.
 
Charles Smiley said:
"NWSL Blunt Axel Nickel Silver Wheelsets 53-371404"?

I'm not sure. They were either for a Athearn SW or a SD9. It's been too long. Both have since had LifeLike chassis substituted to power the Athearn detailed BB shells. I'm kind of glad it all turned out that way frankly.
Click to expand...

They are for a athearn GP7/9 that I'm detailing. Hopefully they are the right wheelsets! The website is a bit confusing on replacement parts.
 
Ugh, just received a response from Bachmann. They sell the complete truck with gears for $15 + S/H. Not sure if that is for 1 truck or the pair. Hoping they just sell the gears, but no luck so far.
 
Anyone ever try and glue the gears on the wheel axles? The split gear on this 44 tonner looks as if it could be glued. Not sure how long it would last, but just wondering if this has been attempted?
 
you can glue it, but not the gear, glue the gear to the shaft...you must ream the gear so that it fits snuggly on the shaft without much stress that will cause it to open up at the split. the gap from the split is going to cause a lot of issues, from just lurching and sometimes jamming to tearing up the other gears it contacts. you must prevent that gap from happening, and any amount of 'press-fit' will cause it to gap.

once you get it reamed out so that it slips on the axle, you can use a strong glue (epoxy worked for me a long time ago) to hold it in place. roughen up the shaft to give the glue something to 'bite'.
 
You must log in or register to reply here.



Back
Top