Thank you for the answer. I knew it was going to be something like this.
So, I have to assemble the engine, balances, take it apart, add weight and test again. Only thing I hate about working on steamers is I am afraid I will bend or break something on the drive wheels.
Thanks again, Ken
I hate Rust
Paul pretty-much has it right. I made a balance plate from a 2"x14" piece of .135" brass simply by soldering a length of .060" brass rod across the bottom at its mid-point, to act as a fulcrum. With the centre of the loco's driver wheelbase over the rod, an imbalanced loco will tip the plate towards its heavy end. To achieve balance, you'll need to find a place to add weight to the lighter end of the loco, and the amount required will vary depending on where the weight will be located. The farther away from the mid-point of the driver wheelbase, the less weight will be required.As noted, most imbalanced steamers are back-heavy due to the weight of the motor, and it's often a simple matter to add additional weight inside the boiler, either as a block or lump of lead, or as sheet lead, wrapped around an existing weight.
Lead is the preferred material for adding weight. It's cheap, readily available, malleable (you can pound it into shape) and easy to cast in simple moulds. I usually get mine free at a local tire shop simply by politely asking for some used wheel balancing weights. Sheet lead, in varying thicknesses, is available from plumbing supply outfits or roofers.
To work safely with lead, exercise a few simple precautions. Always wash your hands thoroughly after handling it, and don't smoke, eat, drink, or pick your nose while while working with lead. When filing lead, work over a newspaper to catch the filings - they can be saved and re-melted. Don't leave lead, lead scraps, or filings where children or pets can have access to it. Small children especially often place things in their mouth and are much more susceptible to lead poisoning than is an adult. At the temperatures that we normally melt lead, the vapours from it are negligible. As temperatures increase, so does the amount of vapour. If you're concerned, wear a properly-fitted two stage respirator.
I use a propane torch to melt the wheel balancing weights in a small metal pot - mine is the lid from an aerosol can, with a wooden handle added. The metal clips and any dirt and paint will float to the surface of the molten lead and can be lifted out with the tip of an old screwdriver.
I make simple moulds using .020" sheet aluminum: it can be scored with a utility knife to facilitate bending, or scored repeatedly and snapped apart like styrene. For short cuts to make tabs, use tin snips.Here's the mould-making process in photos:
Lay out the mould on the aluminum. This is a simple open-top type, with low sides. You could make this same shape with one of the edges as the top - if the weight needs to fit in a tight spot, this may be preferable, as the lead will form a convex meniscus which may need to be filed flat.
Score along the lines with a utility knife - one or two passes where you want to create a bend, and 3 or 4 passes where you wish to break the material:
Once the piece is free from the sheet, use the snips to create the tabs:
...then bend:
Here are some various moulds:
...and the cast weights:
The mould can be opened slightly to remove the casting, then re-straightened for re-use. With careful use, they'll last for several casts.
Some locos require more work than others to bring them into balance. The mould shown here is for a part to replace part of the factory-cast weight in an Athearn USRA 2-8-2. The aluminum was formed around a piece of suitably-sized pipe, then held in shape with soft steel wire. The inserts are to create voids within the mould so that the casting can be more easily shaped (using a mill file) to mate with the remaining part of the factory-supplied weight:
Here's the finished weight (at right) along with the part (next to the boiler shell) to which it will be mated. Note also the weights within the loco's frame:
Also visible in the photo above are new air tanks. These are simply brass tubing into which molten lead was poured. This is an easy way to hide additional weight on almost any loco.
While balancing the Athearn locos was a fairly involved process, I managed to raise the weight from 12.5oz. to 17oz. but more importantly, the weight is balanced, improving the pulling power dramatically.
I performed similar improvements to the Bachmann Consolidation, too. These locos are well-balanced right from the factory, but I managed to increase the weight from 13.25oz. to 15.25oz. while still maintaining the balance. I gave them a tonnage rating identical to the Mikes and often doublehead them in any combination.
Wayne
A simpler and safer (to you), is to use a round pencil (or dowel) and a piece of straight track long enough to hold the loco (without tender). Put the loco on the track and slide the pencil under the track. Move the track until the pencil is in the middle between the drive wheels. Add weight to the lighter side until you get a pretty good balance over the center.
If there's only room for half the weight, then take away the other half from the other end, etc.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
In model railroading terms, steam balancing refers to making sure that each driver axle gets equal amounts of pressure on the rail. Most steamers have the motor in the firebox, making the engines tail heavy to a significant degree. Usually, lead in the smokebox helps to try balance the load. Most times, however, there's not enough lead in the nose.
The best why I've heard to balance a steamer is to remove the tender (obviously), then place a razor blade in a vise or somehow affix the blade so that the edge is straight up and it's level across. Next, place the engine so that either the center driver (say, a 4-6-4, 2-10-2, 2-6-0, etc.) or the center between the two center drivers (2-8-0, 4-4-2, 4-12-2, etc.) is on top of the razor's edge. Now allow the engine to pivot on top of the blade, and it will fall towards the heavy side. Add pieces of lead loosely to the opposite end (small lead chunks like the 1/4 or 1/2 oz. sections) and see if that improves the balance. If you can get it close, use the chunks of lead to determine how much you need to add. Take that much sheet lead or lead shot, and try to affix it to that end, by hook or by crook.
The better balanced the engine is, the better she'll pull. I've actually taken lead out of an engine and it's pulled better, just because it was better balanced.
The reason is that making an engine, say, very tail heavy, actually tries to lift the front drivers right off the rails...just like a teeter-totter. This means that instead of having all your drivers adding to the traction, you may only have the rear axle doing all the work. And that's just not enough friction to get the job done.
Paul A. Cutler III
I think Ken is referring more to weight balance between the front and rear of a steam locomotive and not wheel quartering. A properly balanced locomotive will naturally place more equal weight on all the drivers, but most newer models should not have this problem as much as the cheaper toy train sets of years past.
Correcting an imbalance would require the addition or subtraction of weight, which could be very difficult if not impossible in some cases. The simplest solution is to not buy cheap locomotive models that have been made for the "run around the Christmas tree and then throw them away" train sets.
I don't know if an unbalance situation had an effect on traction.However,it did have nasty consequences on track and loco longevities due to vibrations.This balancing act is called "quartering" in steam loco technical references.
How do you balancing a steam engine? I seen it posted many times that one of the reasons some steam engines don't pull well is because of poor balances. Any tips?
Cuda Ken