RSS Feed for This PostCurrent Article

Disassembling an AHM 0-4-0 Baldwin

From various

I am sure to some of you this is a dumb question, but I would rather be careful. I have an old AHM 0-4-0 Baldwin that I want to take apart. Is the body clipped on or do the screws hold it on?

Has anyone ever tried mounting the body on the Life-Like 0-6-0 chassis? Couldn’t find any of the Bachman tank engines, so I am going to try this one.


There is a single screw just between the stack and the bell. Once it is removed, just pull straight up on the body.

I have mounted the old AHM shell on a Life-Like 0-6-0T chassis. You need to glue the Life-Like weight to the front end of the chassis – or else mount it in the front end of the AHM boiler – to get the balance and weight right. I built a wooden frame to attach to the chassis and hold a nut on its top. A flat head screw went through the screw hole in the AHM shell into the nut on the wood frame. Very simple and it runs well. I did have to trim a tiny bit off each side of the lower cab front to fit over the Life-Like motor.

Ed Cass

As you have probably read from the postings, the screw behind the stack holds the body to the chassis.

If you are interested in remotoring and regearing the original AHM loco, this is also possible as we have sold many of the AHM Diesels and Steam Locos, with new gears and can motors.

FIRST ARE THE GEARS


Most of the original gears split. Sometimes the crack in the gear is hard to find as it is down deep in the bottom of the teeth and usually covered with black gease. The gear which splits is always the gear(s) on the axles. As the axle was pressed into the plastic gear before they cured, the plastic shrunk around the shaft, and when it shrank to the point that it could no longer fit around the shart, the gear split. It is rare today to find one of the original units without broken gears.

Northwest Shortlines (NWSL) makes a replacement set of gears for these engines (which use nearly identical drive mechanisms). The gear set replaces the worms, which are pressed on the longitudinal shaft, and the gears on the axles. The large gear on the motor and the gear it drives are not changed, they do not seem to create the problems of the axles gears.

THE MOTOR


A small can motor can be mounted on a silicone pad to drive the rear gear. A bushing may be necessary, or boaring the hole in the gear may be necessary. this depends on which motor you use. Soldering wires to the original brass (bronze?) motor contacts and then to the motor leads is very simple. Make sure that you get a good gear mesh between the gear on the motor and gear it turns. The motor we used in our repowering projects was the Faulhaber 8mm motor with the 4:1 gear reduction; a bit costly, but a great running motor. A small Sagami or NWSL motor would also work for the conversion. I don’t know of anyone using an open can motor, such as the Mashima, as mounting it in silicone would/could be a problem.

OTHER SUGGTESTIONS


—Adding Weight

Adding weight to both the steam loco and diesel will improve their pulling power and help make better electrical contact with the rails.

—Repairing the Frame

If you unit has run in the past and you have a few hours on it, you may need to repair the bearing box, on which the long drive shaft rests. A piece of thin shim brass, cut to fit in the bearing box, will bring the shaft back to the original position and help the gears stay aligned.

—Making clearence for the New Gears

When/If you do install the new gears, the gears are not the exact size of the original gears. There are no exact replacements. You must change the worms and the gears on the axles. The new axle gears are slightly smaller in diameter than the originals and the worms are a bit larger than the originals. Together, the total of their diameters are the same. With the new gears, the top speed is slightly reduced.

One thing you will need to do when installing the worms on the long shaft is that the gear cover plate will rub against the new worms. There is a channel in the bottom of the gear cover, where the worms are located. You will need to cut rectangular openings in this gear cover, to expose the worms. By opening this hole, the worms will not rub against the cover.

Al Sandrini

You must be logged in to post a comment.