I have a couple of BLI mikados that nose ( waddle) considerably while moving. I know this is a tendancyof rod coupled steam locomotives real and model. The lead and rear drivers have considerable lateral play, most likely to enable the engines to negotiate 18" radius curves.
My question is how to limit the nosing. Might it be possible to shim the axles to limit the lateral play?? Any suggestions will be appreciated.
Possibly adding some washers on the axels may help but watch out for potential shorts and you’ll have to pull one wheel off and then have to get it back on in the same quarter. Have you pulled drivers before?
Chris
Let’s think about this a little differently. Possible causes of nosing (waddling):
Shimming the axles will help with the first cause. It the side rods are one piece, you may only have to shim the front or rear axle instead of both because of the rocker action of a single piece side rod. As pointed out, you will need to make sure you keep the drivers in correct quarter when you remove them to install the washers. I would think about the fiber washers Kadee makes for shimming car and coupler height (or similar) to prevent any short circuit issues from metal washers.
Second cause - easily checked with an NMRA gauge. However, if setting the gauge wider, be careful to maintain correct quarter. Scribing axle and back of driver with a knife blade prior to adjusting gives you a quartering reference if the mechanism is working fine before adjustment.
Back in January 1962 Model Railroader (IIRC), there was an article on improving a Big Boy. Part of the article discussed making the pilot truck self-centering and giving a slight guiding impetus to t
Split R
The correct term for this condition is hunting. This condition is not just limited to BLI. I have Bachmann and other makes that do the same. I am afraid that there is little to do to correct the hunting of the front end of model steamers. Checking and fixing the quartering helps. Making sure each side rod is exactly the same as the other side helps also. Shimming could possibly lead to other problems like derailing on turns and diverging routes. I had noticed that my Bowsers kit built locos did little or no hunting. I experimented with a Bachmann K4s that hunted terribly. I added lead to the boiler as much as could be put in and it seems to have corrected it to the point it is hardly noticed. Locos scale down in size very well but not mass. Another plus with adding weight is better tractive effort.
P.S. If you are running the rubber tired drivers exchange them with the all metal ones that come with it and see if the hunting is reduced.
Pete
Want to prevent it? get rid of it dummy!
Plain N Simply a new or old TROLL.[:D]
[:-^]
Brand new
Buh-bye
if you do decide to try shimming here is a little tip. in order to get washer on a shaft or axle without pulling the wheels or gears try snipping a small section out of the washer. the piece you cut out should be slightly smaller than the shaft diameter. they you can pop the washer onto the shaft from the side and it will stay put.
grizlump
Use your penis. The Penis resolves everything. then there will be no noise.
I’ve had to shim wheels on steam engines to prevent problems before. One way is to glue some thin plastic between the wheel and frame, and the other is to make a C-shaped snap ring (mentioned earlier) to go directly on the axle. Either way should work fine, but the snap ring idea would probably be better.