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I bought this brass 2-8-2 (PFM) in the 1970s. It never ran well. I thought about selling it off. It's a nice shelf model.
Good valve gear but weak motor and poor electrical pickup. I bought a Spectrum 89842 Vanderbuilt long tender for the trucks (dead match). Walthers has been out of them for months, but Peach Tree had lots of them and better pricing.
The new trucks have axle wipers and I added side wipers so the tender produces pickup from both rails - unlike the PFM method. I added a 2 pin cable and connector.
The motor came from a Athearn flywheel chassis - see photo. I fabricated a brass wraparound strap to install it.
Now it's smooth and stall free. BUT! it's very slippery on my 1-1/2 percent grades with 34 inch radius. I can manage about 3 cars before slip.
The boiler is already full, so no room for more weight.
Is this a good time to try bull snot traction aid? Will it work on one axle? How long does that stuff last and does it contaminate the track for other locos?
Surprisingly, removing a little weight might help, if there is no room to add more.
1. Check the leading and trailing trucks to make sure there are no springs exerting too much pressure.
2. Look carefully to see if all the drivers are actually making contact with the rail.
3. Put the engine (without the tender) on a stiff piece of track, then sit that on a round pencil to see where it balances. Balance point ought to be between the second and third driving axle and a little bias to the front is fine.
Many brass engines are tail-heavy and perform poorly on grades. If the drivers are sprung, sometimes substituting softer springs (NWSL made them) can help with adhesion.
I use bullfrog snot on the dead side of the geared driver. it increases pulling power by up to 30% on diesels, and up to 50% on steamers. In my experience it does not dirty the track.
Drivers are all flat -- but the spring force is way too high to do much good. The axles may as well be rigid. Even if it doesn't fix this particular problem, I'd like to make them softer.
I used a digital scale (for light postage) to check this. The total weight is 10.4 oz. The ballance point is at the next to last driver-center (the driver with the crankpin). The lead truck is unsprung and just flops around - but it keeps on the rails. The trail truck has a very light spring and the total of the spring-force, plus the weight of the assembly, is 0.3 oz.
You might be onto something. I added a larger motor with a brass flywheel in the cab area. So it's possible MORE spring force on the trailing truck might transfer the weight a bit more forward. That should do something good going up hills. So I'll try that.
Even if I use the "bullfrog" it won't hurt to improve the basics.
QUOTE: I use bullfrog snot on the dead side of the geared driver. it increases pulling power by up to 30% on diesels, and up to 50% on steamers. In my experience it does not dirty the track.
By dead side you mean the side that is insulated and not contributing to bringing power to the motor - correct?
And yes, steamers just seem inherently more slippery. My little Atlas and LifeLike switchers can pull over 15 cars up the same grade.
Another thing to consider is what I call the "polish" on the drivers. Brass locos came from factory with a nickel plating on the drivers that is very smooth. Until this plating gets worn just a little, the loco will not pull up to its capabilities.
I have brass locos that could barely move themselves when new, but as the "polish" got worn, the pulling capacity greatly increased. My Oriental Limited 2-8-8-2 could only pull about 20 cars when new. It can now handle 45-55 hoppers with no problem at all.
Alan can verify this as he saw it do this before he moved to Milwaukee.
True, running in the mechanism is important, and as the plating wears, the model will pull better all by itself. Still, Bullfrog Snot is a neat thing to have around. With brass steamers, you're getting everything from one geared driver, which drives the others through the siderods. Much less efficient than the 4-6 geared axles you get with a diesel model. I stick with the geared axle only, as I don't want to cause side rod wear. You can't exactly run down to the hobby shop for brass parts, and Max Gray isn't making any!
Any brass-a-holic's parts drawer and selection of screws, crankpins, and so forth is guarded with a firearm! At least those of us who operate their models!
