Can someone of the forum provide the correct part number for the gearbox used on a USH Santa Fe 4-8-4? I would like to find a spare gearbox, but I don't know the right number look for.
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MTH or Lionell??? and what is the item number!
Alan
hopefully someone here will chime in on which one is correct
I don't the part number, but they show up at O scale swap meets.
I just looked at the web catalog that Joe posted, and U 100 looks like the ones that are in my US Hobby 4-8-2 and 4-8-4 engines. Hope this helps.
Alan M, just to let you know USH is US Hobby, they imported brass trains made in Japan from about 1964 to the 1970s. Hope this helps.
Thank you, harley rider, for the suggestion of U-100. I think probably all the big 8-driver USH models used the same gearbox.
I was able to get one (U-100) from Bill Davis at American Scale Models.
@B Smith posted:I was able to get one (U-100) from Bill Davis at American Scale Models.
The Brassmonger himself!,…
Pat
I wonder if a Max Gray/USH post would be helpful for new modelers?
What sort of information are you thinking of posting in regard to Max Gray & USH? I guess people now are not as familiar with these Japanese imports as they used to be.
B Smith, I just thought maybe a file on some of the cars and locomotives might be helpful to new O scalers.
That's a good idea harley rider -- maybe with some photos?
I don't mean to put a damper on this conversation but I feel like I need to mention this. There were two gearboxes from KTM/USH with the compound gears in the center. They look same but the gears and housing are not the same . This includes the axle gears. The parts are not interchangable. My failing memory tells me they went by part numbers U100 & U101. If needed I can attempt to verify.
Jay
Jay, thanks for the gearbox info. With the newest USH/KTM model now 45+ years old, it is good to know what gearbox will work.
Jay, I was able to order a USH U-100 gearbox from Bill Davis, and it looks like the standard gearbox for a Santa Fe 4-8-4, 2-10-4, or other large USH engine. The drive shaft does not protrude from the front end of the box.
Bill also lists a USH U-101 gearbox on his website -- it is an angled gearbox designed for the front engine of an articulated model. It does not stick up as high as the U-100 and therefore won't interfere with side-to-side movement of the front engine. It can be used in conjunction with a gearbox for the rear engine that has an extended drive shaft to carry a universal joint connecting to it . I am guessing (just guessing) that the rear engine would have had a basic U-100 box with an extended shaft (?).
Okay, so the one I'm talking about isn't the U-101. As I tried to state, I wasn't sure of the number. What I'm trying to say is, there were two gearboxes, the U-100 and another that looked identical but is not the same internally. If your model has the other box the U-100 won't fit. Hopefully, you got lucky.
Jay
Maybe this will help om me trying to explain my word of caution. I will attempt to attach some photos. In the photos you will see the halves of two tall KTM gearboxes. Externally they look very similar. Internally they are different. I'm also going to attach photos of the two different axle gears. I call them large & small. The large is a U-103 (with 22 teeth). The small is a U-104 and has 20 teeth. The compound gears are different also. Luckilly, NWSL makes replacements. The other good news is, the U-100 is the most common so you're probably good. If there's a problem, please let me know and maybe I can assist.
Jay
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Thanks Jay C -- I can see what you mean about the differences between the two. If I run into problems, I will definitely get in touch with you for help.
@B Smith posted:Can someone of the forum provide the correct part number for the gearbox used on a USH Santa Fe 4-8-4? I would like to find a spare gearbox, but I don't know the right number look for.
My experience is that the gearbox itself almost never fails. Rather, the plastic idler gears is the part that fails. Why spend $100 for a box when the idler gear is only $10. The cheapest place for an idler gear for this gearbox is All Nation Trains.
Thank you for this suggestion.
Do you happen to have the SKU for the idler gear from All Nation?
Regarding the idler/compound gear, the NWSL one is composed of two gears screwed together. Each of these screws is another point of failure and that tiny screw, if it becomes loose, could cause damage to the worm or axle gear. The All Nation one is made as single unit without screws.
@B Smith posted:Do you happen to have the SKU for the idler gear from All Nation?
You get what you pay for. The best, if you can find them, are the original KTM bronze compound gears.
A 3D printed set of gears? No thanks, not for me.
Jay
@Jay C posted:You get what you pay for. The best, if you can find them, are the original KTM bronze compound gears.
A 3D printed set of gears? No thanks, not for me.
Jay
Jay,
i couldn’t agree more regarding bronze compound/idler gears. The problem is that they are exceedingly rare. Someone is probably hoarding them. Not sure why. A bronze compound gear will outlast the lives of a couple owners assuming normal lubrication.
Not sure I agree with you get what you pay for. The NWSL is $25 and put together with two tiny screws. I have had to ream the center of these gears to get them to fit—in short not the best machining. Plus one has to worry about some screw failing.
I have used the All Nation 3D printed version for $10 and never had to to do any reaming and appears to work fine in service. Time will tell. Moreover, All Nation actually answers their phone with good support. The new NWSL seem to just do email and response fairly delayed sometimes 5 days. Do they even have phone number these days? No phone number on their website as of this morning.
So for $10 you get something that fits right and better customer service. The bargain seems obvious to me.
Rob
Rob,
I guess I like the NWSL second best. I just like machined Delrin over 3D prints. Never had a problem with them fitting. One thing to be aware of, there are two different versions (sizes) of the compound gears. Okay we've flogged the dead horse into submission. Another issue with the plastic compound gears, and possibly the printed version, is the heat generated under sustained, and heavy use causing damage to the gears. If someone doesn't believe me, run the model for a while and then feel the gearbox housing. I've seen a lot of heat...maybe enough to weaken the material the gears are made of. I'm sure this is compounded with age. The design of the input bearings and plastic thrust washers create too much friction, thus causing the heat. My solution isn't original so I can't take credit for it. I install 4mm flanged ball bearings. Very little, if any, heat generated. Once again, I will try to attach a link to a photobucket album showing numerous, and probably lots of duplicate, photos.
https://photobucket.com/u/jayc...17-a096-a8d81ef5e1d7
Jay
@Jay C posted:Rob,
I guess I like the NWSL second best. I just like machined Delrin over 3D prints. Never had a problem with them fitting. One thing to be aware of, there are two different versions (sizes) of the compound gears. Okay we've flogged the dead horse into submission. Another issue with the plastic compound gears, and possibly the printed version, is the heat generated under sustained, and heavy use causing damage to the gears. If someone doesn't believe me, run the model for a while and then feel the gearbox housing. I've seen a lot of heat...maybe enough to weaken the material the gears are made of. I'm sure this is compounded with age. The design of the input bearings and plastic thrust washers create too much friction, thus causing the heat. My solution isn't original so I can't take credit for it. I install 4mm flanged ball bearing. Very little, if any, heat generated. Once again, I will try to attach a link to a photobucket album showing numerous, and probably lots of duplicate, photos.
https://photobucket.com/u/jayc...17-a096-a8d81ef5e1d7
Jay
Jay,
Thank you for the nice reply.
Yes I am aware of the two different sizes/gear ratios. I have found that the KTM USH steam locos with the larger axle gear and different idler to be stock on only the USRA 0-8-0. All the others have the the more common U-100 in the non articulated steam. That’s just my experience.
i agree that there is a lot more experience out there with delrin which NWSL uses. I bought my NWSL idler gears a couple years ago. Mine could be a less than optimal batch. On the other hand, your well fitting NWSL gears maybe products of the old NWSL proprietors who had great stuff.
I completely agree with the ball bearing approach which Kleinschmidt also utilized in his drive upgrades. What are you charging to do this upgrade? How far are you booked out? Feel free to answer me via email. I’m the guy who keeps on asking about Lobaugh gearboxes.
I have a lathe maybe I can swing by Clovis and watch you make this upgrade? I visit CA about once a month.
Respectfully,
Rob
Rob,
I'm sure we can work it out. By the way, no lathe required.
Jay
Thanks swrr -- I ordered the printed gear set from All Nation as an experiment. Their catalog is nominally 572 pages online, so I was not sure where to look. In fact, I did not even know that someone had taken over the original All Nation line -- I thought it was completely defunct.
Jay,
Thanks for the follow-up. i surmise one can make the mods with a drill press then. I was unable to open the photobucket link.
Rob
@B Smith posted:Thanks swrr -- I ordered the printed gear set from All Nation as an experiment. Their catalog is nominally 572 pages online, so I was not sure where to look. In fact, I did not even know that someone had taken over the original All Nation line -- I thought it was completely defunct.
Let me know how it works out for you.
I received two printed combination worm/idler gear replacements from All Nation for the USH U-100 gearbox, and they look very clean and nicely made. How durable they are remains to be seen. I don't run my USH Northern a whole lot and it's under a relatively light load anyway, so they may be fine. Bill Davis has some original brass USH combination gears available for $45/each.
@B Smith posted:I received two printed combination worm/idler gear replacements from All Nation for the USH U-100 gearbox, and they look very clean and nicely made. How durable they are remains to be seen. I don't run my USH Northern a whole lot and it's under a relatively light load anyway, so they may be fine. Bill Davis has some original brass USH combination gears available for $45/each.
Good to hear. I contacted Bill Davis regarding the idler gear. He only has the metal idler gear for the higher ratio axle gear at 15.7:1. The standard gear ratio is about 25:1.
The printed combination gear set appears to have a smaller pinion than the set shown in Bill's listing, which implies that it provides the 25:1 ratio.
