I've been fiddling with my light mountain and I found the masking tape shimms on the traction tire wheel bearings just wasn't cutting it. Therefore more of a fix was in order. With the TT's shimmed, there still isn't a sufficient weight transfer. So this time I pulled the rear -most wheels out and filed a small portion off of the bearing blocks. This mod allows the rear wheels to move upward more and transfer more weight onto the traction tires. So far 20 freight cars and 6 con cor heavyweight coaches (all on flat land, no grades on the layout).
I haven't attempted the traction tire shim yet but am getting ready to. Did you leave the masking tape shims in place in addition to filing the bearing blocks? ...Tom
I left the masking tape shims in place. Make sure you don't over tighten the bottom plate, the wheels need to move from side to side easily or derailments will occur
Wow, this is interesting, I have two of the mountains, and both will easily pull 25 car trains on level track on my layout. I must have lucked out with the two I have, because I have never had to alter them at all to get them to perform, other than replace the tender wheels with Kato caboose units.
I would guess that the concor heavyweights are about 3 freight cars apiece in weight (I put some led in them to add even more weight). So we are looking at about 38 freight cars and a caboose with zero wheel slip so far. As soon as I get the rest of my fleet outfitted with low pro wheels (atlas 55 track) then I can add about 20 more cars. I also used it to pull my atlas track cleaning car, I usually have to double-head in order to pull it around the track. This unit was quite a dog when I recieved it. It would only pull about 15 cars with a bit of wheel slip. So this is quite an upgrade compared to its orginal performance.
Awwww shaving cream. Considering the identity of the guy who started this topic, I thought that someone had figured out how to bash a Mk-2 from a USRA light 4-8-2 (although the drivers would be too large; sixty-nine inches on the USRA, fifty-eight on the Mk-2). The SP's first 2-8-2s were class Mk-2, 1911 Baldwin contraptions, some of which lasted until the end of steam. I am assuming that the filing of the bearing blocks does not cause the locomotive to tail. Have you tried this without shimming the tyred driver? I wonder if the filing alone will help this one. From what I understand, Bachpersonn has addressed the problem of the tyred driver's failure to make proper contact with the rails in subsequent runs of the USRA light 4-8-2. Thus, if you have one from the second run or later, the pulling power is supposed to be allright.
Closer than you might think. Someone, I forget who, on the Bachmann forum who measured them said the 4-8-2 drivers were closer to 63 inches. When I first saw mine I thought I had received a Z Scale loco in error. I replaced the loco shell with a heavy Pacific shell, actually two of them spliced to be long enough, and it still is the shortest in stature steam loco I have. I couldn't resist. If yours pulls 6 or more heavyweights on a 2% grade you likely have a good puller other than the first run. Actually I don't think there is a way to know which run except by trying it. Remove the traction tire driver and place the shims on the bearing blocks for that driver (on the surfaces of the bearing blocks that rest on the slots in the loco frame). Some have reported that merely turning one bearing block a quarter turn from the other does the trick. That didn't work with mine. Ben
Thanks gang for this advice. I just did mine using a tiny strip of 3M blue masking tape to shim the traction tire mounted drive wheel downward. It made all the difference in the world. Re-gauging the drive wheels on these Bachmann steamers causes the pillow blocks(bearings) to flop around. I used the same blue masking tape to hold the blocks in place on just the wheel (axle) that has the eccentrics. This also worked great. I did a long term fix for this on a 4-8-2 that I had completely dis-assembled. I used tiny brass washers on the inside of the driver axles.
It may have been me who mentioned that on the Bachpersonn Phorum. I did a rough measurement and came up with sixty-three or so inches and asked Mr. B-mann if this was deliberate to allow it to negotiate sharper curves. Mr.Bach-Man replied only that eh thought that they looked nice. Yeah, they do, but my question???? Anyhow, while I am mentioning SP mikados, I found a site concerning USRA power. That site mentioned that the USRA assigned five USRA heavy mikados to the El Paso and Southwestern, a railroad that the SP bought in 1924. The EP&SW mikados were Mk-7, Mk-8 and Mk-9, all ALCo contraptions. Mk-7 showed up in 1913 and 1916, pre-USRA; Mk-5, 1918, right time for USRA, Mk-9, 1920 maybe USRA but maybe copies. There were ten Mk-7 and Mk-9, but FIVE Mk-8. Could Mk-8s have been the USRA power? Kato numbered its SP mikados for Mk-7s, which were pre-USRA power. There were coal burners in EP&SW territory, the AC-9s come to mind even if they did show up after 1924. I do not know much about EP&SW power except what made it to California. That power burned oil in California. So, the questions: 1. Were the Mk-8s USRA heavy mikados? 2. Did the SP keep them after the EP&SW acquisition? 3. Did the SP convert any of them to oil? 4. Did any of them ever show up in California? They lasted until 1954, which would have given them opportunity to make it to California. Does anyone know? Maybe Mr. Straw or any of you other SP steam nuts? Thanks.
Recieved my new SP 4-8-2 mountain from a recent ebay auction yesterday. I put it on the track an wow, to my dismay it didn't move. Hmmm, I shoved it a little and it proceeded to studder around the track. Hmmm some more. I pulled my vandy tender off my old one (better tender pickup) and the loco was off and running, or should I say spinning. It couldn't pull the tender (which is about 3/4 full of lead). And when it did start moving, it wobbled horribly. ARGGGG. Out came the masking tape, had to shim the TT wheels as well as the second drivers to stop the wobble. as the bearing blocks had way to much play. I put the lid back on and now she purrs like a kitten around the track. All I can say is the Bmann QA folks should be looking for new work.
The Bachpersonn SPECTRUM USRA Standard and Long tenders transmit electric from the tender to the locomotive through a pair of stiff wires in the drawbar that are supposed to make contact with a pair of posts on the locomotive. Unfortunately, when the locomotive comes from the factory, often the wires do not make proper contact. What you must do is separate the tender and the locomotive, then pinch inward the two stiff wires. Finally, re-attatch the tender to the locomotive and ninety-five per-cent of the time, you will have solved the problem. The slopeback and USRA Switcher tender on the B-mann Standard Line 0-6-0/'prairie' also has an economy version of the SPECTRUM drawbar. You must also pinch in these wires, just take care lest you pinch too hard and the wires come unsoldered from the drawbar. What I do is use a pair of needlenose pliers to grip the drawbar and stiff wires a few centimetres ahead of the solder joints, then pinch inward. This takes the stress off the solder joints.
Doesn't seem so if the MK-8's ended up with SP in 1924. Reasoning: From Huddleston (Uncle Sam's Locomotives: The USRA and the Nation's Railroads) "Not understandable is why the EP&SW sent its five heavy Mikes to the Great Northern around 1920." And from steamlocomotive.com: Great Northern's "Class O-3 were USRA Mikado-Heavy locomotives, four were diverted from SP&S, five were received from EP&SW." Ben
"Not understandable is why the EP&SW sent its five heavy Mikes to the Great Northern around 1920." Actually, many of the USRA locos that were assigned to roads got shifted around.... It may be lost to time if this was simply because the USRA administrators were balancing power needs against the traffic at that time or if it was because the mechanical departments of the railroads involved just didn't want the "foreign" design power. In spite of the excellent designs of all the USRA types, the concept of "not invented here" was strong on many roads. Others, however, liked the USRA designs so well that they were duplicated in quantity. Some of the last steam locomotives built, the N&W 0-8-0s, were modernized copies of the C&O locos which were essentially USRA 0-8-0 locos.... a very widespread and accepted locomotive as was the USRA 0-6-0. Charlie Vlk
Yep, EP&SW questioned why the USRA Mikes that had a larger heating surface than its own Mikes should have 1/2 inch smaller diameter exhaust nozzles. This while unable to decide whether this difference was good or bad, and admitting the USRA engines were fuel efficient and they steamed and operated well. USRA responded the size was not "prescribed" and was a matter of local adjustment. Maybe that was not the answer EP&SW wanted to hear? Ben
