Bachmann HO Santa Fe 5012 steam loco w/ tender

Started by Tom Cat, August 07, 2011, 09:48:30 PM

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Tom Cat

I just purchased this engine which has some great detail and the Chug - Chug from the tender is really cool. However, the wheels don't want to turn very well. Sooo, I opened her up. Motor works very well, along with the light & looks to be an element for smoke. Great running gear, very realistic. But here is the issue, the wheels have separated from the center shaft on all wheels. I figure to glue them back but I have no clue to the rotation timing of the drive assembly for each side. I've looked at some models on Ebay that have photos of each side. Kinda looks like one side is a little more advanced the the other. Others look like each side is exactly opposite from the other. Since I plan to use a strong glue, I figure I have one shot at getting this right.

J3a-614

Tom Cat, both models and the real engines have crankpins offset from each other by 90 degrees, or a quarter turn.  This is called "quartering," and normally the right side "leads," in what is called "right-hand lead."  Most railroads used this, but the Pennsylvania Railroad, apparently in a desire to set its own standards, chose left-hand lead.  Technically, this makes no difference at all.  Quartering was needed for steam locomotives, as they have no flywheel, such as a stationary engine has; failure to have the cranks offset like this could lead to the engine being stopped on "dead center," with all moving components--piston, piston rod, connecting rod, and crankpin--in a single line, like a column, with no starting leverage available.  With the crankpins offset in quartering, at least one side of the engine will not be on dead center, and the locomotive can be self-starting at 0 rpm, even with heavy tonnage.

Quartering is serious business, ideally requiring what is called a "quartering jig" to get all crankpins aligned consistently; failure to have all wheels on correct quarter will lead to binds and assorted other problems, as rods try to adjust their inflexible lengths to distances that become longer and shorter as the wheels turn. 

The Bachmann 2-10-4 you bought is currently available; I assume you got it new.  Unless you live very far from a post office or hobby shop, I would send the locomotive back for repair or replacement.  Heck, I would do so even if my Post Office was some distance away; like I said, quartering is serious business, requiring a pretty good deal of precision.

Doneldon

#2
TC-

I'll assume you purchased this loco used since you would otherwise have sent it straight back to Bachmann. The first thing I'd do is see about getting my money back, whether you bought it at a garage sale or on ebay. Failing that, you are in a bit of a pickle.

You are correct that the counterweights on a given axle are in relation to one another. It is also true that the rest of the weights will be spaced out for overall dynamic balance and starting ability. (Don't ask; it can get pretty complicated. Figuring out the pattern can be the devil's work. It requires that you either find an identical model or the original prototype. Another model shouldn't be too hard; just look in catalogs and model railroad magazines. Your model may or may not have an actual prototype so that could be impossible. The good news is that you should be able to use the counterbalancing/quartering pattern from any loco with the same number of driven axles. The very good news is that you probably don't need to do any of those things. (I apologize for playing with you.) If you inspect the broken spokes of your wheels they will tell you just how to do the repair. That is, every spoke will be broken in a slightly different location and with slightly differently shaped broken ends. So, get out your magnifying glass and some glue and go to work. I suggest the liquid glue which melts the plastic back together, "welding" it. Or, line up one wheel on an axle and position the other such that the engineer's side weight is 1/4 turn (90o) ahead (clockwise) of the one on the left. Once you have one axle correct you can just align the other axles with wherever the side rods show they need to be connected. The first one is the difficult one. With the clues you'll see with your magnifying glass you should be able to finish the job without much trouble because the spokes will show the quartering to you. The only negative thing I must say is that I can't think of any way all of the axles on both sides of a locomotive could break away except by abuse. Consequently, you may get all of the repairs made to your locomotive only to find out that it still doesn't work correctly. I believe that's less likely in your case since it sounds like you have checked pretty much everything else out with good results.

But, I still think sending it to Bachmann, even if you must pay for the repair is a better way to go. You'll be sure that the quartering is correct and, more important, you'll have OEM wheel assemblies, not a bunch of plastic wheels which have been glued.

In any event, try to enjoy your challenge.
                                                                                      -- D

Tom Cat

Opps, I did not know this model was still available. I'm very new to HO as I was given a complete 1960's Lionel Sante Fe passenger set last Christmas. I made a 4 x 8 layout with one track and got hooked and added siding with a couple of switches. Now, in less than 6 months, I have 3 tracks, 4 buildings (I made them), 2 spurs and a 2nd New Haven passenger train. I made one of the buildings, is a "Railroad Museum" and I put a display caboose next to it (Fullerton, CA station has one next to the depot) and thought a old steam locomotive display would really look cool. That's why I picked up the engine. When I noticed the tender had a speaker on the bottom, I hooked it up and "chug chug chug" that is timed with the power pack, I wanted to get the engine to run. Oh well, if I can't she will just be a display piece.

Thanks for the tips. Even at 65 I'm still learing. Great Hobby!

Doneldon

TC-

Welcome to model railroading. It sounds like you have a pretty bad case of trainitis. I like that in a person.

                                                                                                       -- D