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Adding weight to a Bachmann Steam Loco Locos and rolling stock
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Regular poster 300 posts ajcaptain Regular poster 300 posts
ajcaptain
I'm posting this as it may be useful to other folks with steam locos. I just purchased an HO Bachmann 2-8-4 Berkshire steam loco from MRH sponsor Yankee Dabbler. It's not a spectrum model. I model in the diesel era, but I think steam locos are cool. So I got one. My intention was to use it to haul a "museum" passenger train consisting of 7 heavyweight passenger cars. Much to my dismay, out of the box, it wouldn't budge the train and went into wheel slip. I even got wheel slip running just the loco on a 2% grade on a 30 inch radius curve. Not good. I figured that the loco might be light. I weighed a couple of my 6 axle diesels, and they came in at around 18 ozs. The Berkshire weight was 14 ozs. So, adding weight seemed to be the thing to do. Next, I removed the pilot and trailing truck from the loco. I took the weight over the rearmost drive wheels, and it was 9.55 ozs. Not bad. Unfortunately, the weight over the very front drive wheels was 4.6 ozs. I wonder if this unbalance is common with steam locos. I figured that ideally, the weight should be distributed equally across the drive wheels, so weight needed to added to the front of the loco. Off came the boiler shell so I could figure out where and how to add weight. There was some room right behind the headlight and on the weight already in place. I went to Hobby Lobby and purchased a 3 oz packet of tungsten weights and 1 oz of tungsten putty. This stuff is expensive, but I used their 40% off coupons on both of them. Tungsten is heavier than lead, and one can get more weight in the limited space available. I found the tungsten weights to be far denser than the putty, but there is nothing you can do to change the shape of the weights. I got four of the large tungsten cylinders tucked in behind the headlight. I wrapped them in electrical tape as it made them fit better and would protect against a short with the headlight wiring. Tungsten is an electrical conductor. All in all, I got just about the entire 4 ozs into the front of the loco. Weight is now 9.45 ozs on the rearmost drive wheels and 9.55 ozs on the front most drive wheels (pilot and trailing trucks attached). Huge difference. The loco can now pull the entire 7 car train up the 2% 30 inch radius grade. It has some wheel slip, but it does it. I was concerned about the current draw, and that if it was too high, that it might blow the decoder or damage the motor. I checked it out, and measured .280 amps as the max being used. I don't think that's a problem. At least I hope it's not. I'm now thinking that using Bullfrog Snot would help even more. I would only be able to apply it the drivers on one side as this Bachmann loco draws power from the loco on one rail and the tender for the other rail. Could using the Snot on just one side cause tracking problems? I'm hoping someone knows. Hope this info can help someone. John C

John C
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Ironhand_13 Frequent poster 702 posts
Ironhand_13

Welcome to steam!

I don't have the Berkshire but a spectrum 2-8-0 and a couple of 2-6-0 economy's.  The Bullfrog Snot wouldn't hurt, and is worth a shot.  You won't get wheel slip I'd imagine, but maybe a stall...so maybe it would hurt??  I've used it with success in the past.  I am glad that at least it could pull 7 passenger cars up a 2%, so that means there's hope!  
-Steve in Iowa City
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locoi1sa Regular poster 310 posts
locoi1sa

Make the cars roll easier.

   John.

  Bachmann and their Spectrum line are light on their feet. Adding the weight evenly front to rear is the key to helping. Do not use the snot. Always allow the wheels to spin. And remove the springs on the lead and trailing trucks.

  Seven of the HW Spectrum cars is really good for a plastic steamer to pull. Check out the trucks on the cars. Some have used a drip of oil to the axles to help out the loco.

       Pete
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ajcaptain Regular poster 300 posts
ajcaptain

"You won't get wheel slip I'd

"You won't get wheel slip I'd imagine, but maybe a stall...so maybe it would hurt?" That's what I'm afraid of. Stalling would pump up the amps. "Check out the trucks on the cars." Yes, that's next. This train was previously pulled by an Athearn Genesis F7A and B unit. Both were powered, so rolling resistance wasn't a big deal. Now it is, so I'll be working on each car to get the best roll possible. I'm just amazed by the improvement made by adding weight and balancing it over the drive wheels. One must wonder why the manufacturer didn't do it in the first place. how much production cost could it possibly have added? Oh, well. John C

John C
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IrishRover Prolific poster 1,660 posts
IrishRover

Tungsten weights

Good job making the loco run like that--I'll remember that for the future.  Thanks for sharing the info; it will be useful later.  Where else might one find tungsten weights?  I might want to go with them, but Hobby Lobby is a supplier I wouldn't touch with a ten foot pole.
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michaelrose55 Super User 3,458 posts
michaelrose55

Where else might one find

Quote:

Where else might one find tungsten weights?  I might want to go with them, but Hobby Lobby is a supplier I wouldn't touch with a ten foot pole.

Try Amazon, they have the weights & the putty.

Michael

The Breitenbach - Rosenheim Railroad V4
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ajcaptain Regular poster 300 posts
ajcaptain

pinewood derby suppliers

Suppliers of pinewood derby cars carry them. Shops that carry RC planes might also. Here's a place that seems to have decent prices. http://www.pinewoodpro.com/pinewood-derby-tungsten-weights.htm John C

John C
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MikeM Frequent poster 672 posts
MikeM

These guys have tungsten in several forms

http://www.maximum-velocity.com/pinewood_derby_weight.htm

MikeM
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