N Scale Hi Rail - Retro Hollow Core Door Layout

[nickelplate759]

I have an E60 without cracked gears, but the motor is so wimpy and the drive has so much friction that it still has trouble getting out of it's own way.
Also, the trucks all but scrape the railhead, and the wheel treads are way too wide.

I have plans for an E60 Resurrection project, but to do it well likely requires a whole new mechanism, and that requires some mechanism bashing.

[wm3798]

If Bachmann white nylon gears could be repaired, there wouldn't be so many of their models of that vintage getting dumped every day on Flea Bay.  The metal axles fit into the gears, and the nylon shrinks over time and the gear splits between teeth of the gear, creating an uneven space that clicks when it pass through the worm.  The nature of the material, the need for it to be lubed, and the fact that it will be in constant motion makes any attempt at a glued repair as being rather tenuous.

I think the motor itself can be easily replaced, it's about the same size as the very robust unit found in Life Like lead sled drives, and the motor shaft appears to be the same, so it would just be a matter of getting the contacts to meet the split frame and changing the universal on the shaft.

But the failure of the gears in the trucks would have to be dealt with more comprehensively.  I don't have a Trix U-30 drive handy, and those trucks only offer two drive axles and an idler, but that's the only truck I can think of that might close enough in dimension to Frankenstein into it. 

Lee

[diezmon]

If Bachmann white nylon gears could be repaired, there wouldn't be so many of their models of that vintage getting dumped every day on Flea Bay.  The metal axles fit into the gears, and the nylon shrinks over time and the gear splits between teeth of the gear, creating an uneven space that clicks when it pass through the worm.  The nature of the material, the need for it to be lubed, and the fact that it will be in constant motion makes any attempt at a glued repair as being rather tenuous.

I think the motor itself can be easily replaced, it's about the same size as the very robust unit found in Life Like lead sled drives, and the motor shaft appears to be the same, so it would just be a matter of getting the contacts to meet the split frame and changing the universal on the shaft.

But the failure of the gears in the trucks would have to be dealt with more comprehensively.  I don't have a Trix U-30 drive handy, and those trucks only offer two drive axles and an idler, but that's the only truck I can think of that might close enough in dimension to Frankenstein into it. 

Lee

Could you replace the wheel sets?  maybe you'll get lucky and they're close, or the same?
https://estore.bachmanntrains.com/index.php?main_page=product_info&cPath=70_117&products_id=265

Or there's always this
https://www.ebay.com/c/1624611850

[wm3798]

Sadly, the gear on the E-60 is a much larger diameter.  There's about 30 minutes left on the auction, I'll see if I can dive bomb it at the last minute and still get it reasonably cheap.

Lee

[wm3798]

Meh.  It went up over $35...  Between that and the one I got last week, that's too much of an investment with the level or risk I'm willing to take.

Oh well.  Add it to the list of things to fix...

[peteski]

If Bachmann white nylon gears could be repaired, there wouldn't be so many of their models of that vintage getting dumped every day on Flea Bay.  The metal axles fit into the gears, and the nylon shrinks over time and the gear splits between teeth of the gear, creating an uneven space that clicks when it pass through the worm.  The nature of the material, the need for it to be lubed, and the fact that it will be in constant motion makes any attempt at a glued repair as being rather tenuous.

In most cases the gears can be repaired. Like Doug mentioned, installing (thin-wall brass, or even hypodermic stainless tubing) sleeves (or rings), over the cracked tube.  If the sleeve dimension is chosen properly, it will close up the crack (which will also close up the crack in the gear).  The sleeve can be glued by first roughening the axle tube surface with some fine grit sandpaper, installing the sleeve (to close up the crack), then flowing some thin CA between the metal tubing and axle tube.  making sure thievery is clean and grease or oil free is also vital.

While the sleeving process will not be 100% perfect, it should make the model quite usable.  It is also a bit cumbersome, and not everybody wants to fuss with it. That is why you see locos of models with un-fixed split axle tubes offered for sale.

[Ed Kapuscinski]

Especially when you can just cram a Kato SD40 mech under there...

[nickelplate759]

Especially when you can just cram a Kato SD40 mech under there...

You can,  but it will look funny.  Too short and very different trucks.   An SD50 would be better,  if you could fit GE trucks to it

[Steveruger45]

Or perhaps a Kato c30-7 mechanism.   Even that maybe a little short too.

[Doug G.]

Yeah, the cumbersome part. I wish I had a quick and easy way to slice off short lengths of the tubing for the sleeves. On my 4-8-4, I used a Dremel cut-off disc and then filed them to the correct length. In the old consolidation I'm in the middle of, I think they're the same but on the trolley, they need to be only 2mm.

I'm thinking of seeing if a local machine shop can cut them off for me. That's really the only fiddly part. Putting them on and putting the loco back together isn't a real big deal. I didn't glue the sleeves as they are a pretty good friction fit on the axles. I did have to increase the hole diameters a bit in the inner plastic frame so the metal axles would rest on the two outer metal frame pieces for electrical pickup.

My Northern runs great after the fix.

I still say it's a poor design. Mehano had the correct idea with plastic axle ends plugging into holes in the wheels. If only they could have been a little more precise in drilling the holes to avoid wobble.

Doug

[peteski]

Yeah, the cumbersome part. I wish I had a quick and easy way to slice off short lengths of the tubing for the sleeves. On my 4-8-4, I used a Dremel cut-off disc and then filed them to the correct length. In the old consolidation I'm in the middle of, I think they're the same but on the trolley, they need to be only 2mm.

I'm fortunate to own a Sherline lathe.  But the standard cut-off tool is too wide to cut thin-wall brass tubing, so I made a very thin cut-off tool from a single edge razor blade. It works great!

[Doug G.]

Yes, a lathe. I don't have one. Where I worked years ago, we had a complete machine shop and I was able to make a tool to reach into the grooves on Mehano traction tire wheels and make them concentric to correct wobble.

I used to true up commutators too. The Mehano commutators weren't as bad as the Rivarossi ones though. Some of those were very bad.

Doug

[wm3798]

Okay, so the trick is to sleeve the female fitting molded into the gear, right?  So the correct diameter brass tube would be snug enough to close and hold the crack stable enough to allow the gears to mesh properly, even when the axle is pressed into the gear opening. 
And since the brass sleeve is located on either side of the gear, there is no problem with creating an electrical bridge via the axles...  Am I missing anything?  If I'm off the mark, I would appreciate a photo of the correct configuration for the repair.

While using a Kato drive is a fascinating twist, I'm not interested in using a $100 mechanism to salvage a $30 locomotive.  I'd like to try the repair route first.  I also have an old Bachmann Mikado with a similar issue (you may recall I tried replacing the cracked gears with a 3D printed set, but they also failed)  The metal sleeve idea sounds like a good place to start over.

Lee

[Doug G.]

I don't have a picture but the two sleeves go around the plastic axle on each side of the gear. And yes, then just plug the metal axles/bosses on the wheel, themselves, into the holes in the plastic axles as usual after the plastic axles are back in the frame. There isn't a danger of a short at all since the sleeves are insulated from each other by the gear. It sounds like you have the idea correct.

The sleeves, being fairly tight around the plastic, hold the cracks closed. The axles will still fit through the holes in the inner plastic frame but they will hold the metal wheel axles away from the two outer metal frame pieces and there will be no current pickup. The holes in the plastic inner frame need to be enlarged just a bit to allow the metal axles to contact the outer metal frame pieces as happens with the original configuration.

The above is for the 4-8-4 and 2-8-0, of course and other locos with different pickup contact configurations will not need the hole enlargement step. The trolley is like this.

Doug

[CRL]

Just a thought, but have you contacted Northwest Shortline to see if they have any gears that would be a replacement fit?