Model Railroading > overland models soldered gear tower, gear box problems

I have three OMI models powered this way, a GE 45t switcher and two MILW steeple cab electrics.

The diesel does not move when the motor turns and I have not tried the electrics for some time.

Has anyone had experience with this drive? Is repair possible?

I have not had any luck on the rest of the internet concerning this. Thanks.

Posted from Windows Phone OS 7

It's possible for the motor to have lost connection with the drive line, even though it appears to be connected. This would be if a gear was jammed or similar. For that matter the gear could be spinning on it's center, but the gear turning would have a different sound and vibration.

Anyways, a little ACC glue would hold the shaft to the drive line long enough to confirm that theory. Same with the gear, etc.

Or maybe I mis-understood.

I find that Overland gears break easily. Not sure if the gear is the same as the one for the Tower 55 (Overland) GEVO. We have gear set for the GEVO available.

I had a brand new Overland U28CG run about 3 feet before a gear broke.

Jeff Smith
Lakewood, CA
RailMaster Hobbies

The drive line connection to the worm gears on each trunk is solid. They turn freely and will stall the motor if held.

Posted from Windows Phone OS 7

Jeff,

My best guess is the problem is in the spur gears coming down the tower. One or both of this pair is either split or slipped off it's shaft and has slipped away from the gear path.

The biggest problem is the geartower and the gearbox are constructed from plates of brass sheet which are soldered together at the corners. I am sure I can take these apart but it is not likely I would ever get them back together in alignment for all the gear and axle shafts.

I am thinking I might use an xacto saw to make a couple of cuts at the top and bottom of one side of the gear tower to take a plate with two spur gear bearings out to remove the tower spur gears out. This could be epoxied back after the gear issue is remedied.

I am just hoping to contact someone who might have experience with the same issue to gain insight about what to expect before I dig out the cutting implements.

Posted from Windows Phone OS 7



Edited 1 time(s). Last edit at 07/24/14 14:53 by fbe.

I see NWSL has a wide range of KMT spur gears in nylon and brass versions. Does anyone know if these are an OMI match?

Posted from Windows Phone OS 7

There is hope, NWSL offers a complete set of replacement gears for this unit.

So now I will razor saw out a panel on each gear tower to see what which parts I will need to order.

If there were not connecting rods on the unit I might be able to replace the trucks with the NWSL Stanton powered trucks. Maybe I will go that route with the OMI MILW steeplecabs if they come up crippled.

Posted from Windows Phone OS 7

Wow,reading this post is pretty distressing!! Those models were not cheap and to go 3 feet and break...........? Did OMI make good on these? I am in O and have a number of brass models. Some run super right out of the box-Glacier Park, others not so well. BUT they all can be tuned up and worked on to get them right. My personal standard is to run at 1 smph or less. It can be done. I have no ideas on how to fix a soldered gear box. I feel bad for you guys.

Peter

Perhaps this model was built in the 1970s in Korea? I understand the quality back then was very lacking.

Yes, this is from L. S. Models of Korea. It looks sweet and used to run well. I think all will be well when I effect repairs. As long as the problems stay out of the gear box where the side rods are repairs are direct. If the wheels need to come out to change out the spur or axles then the quartered outside cranks need to be unsoldered.

Posted from Windows Phone OS 7

I cut open the gear tower tonight. Right below the worm is a compound gear with a 22 tooth gear which is on the same shaft as a smaller 12 tooth gear. The large gear connects to the worm and transfers the motion to the small gear which connects to the spur and axle gears. Unfortunately the small gear slips on the shaft so that is where the motor motion stops.

I see three possible solutions. A) Replace one or both gears with new NWSL gears. B)Pin both gears together with fine wire but this might weaken and split the smaller gear. C) Knurl the shaft under the smaller gear. I think I will go with Plan A.

The length of the gear tower is soldered on both sides of the box. Once two razor saw cuts are made it is possible force a round end xacto blade into the joint and break out this plate. NWSL recommends Permatex orange to reattach this plate once the gear work is done.

Stay tuned.

Update: Optivisor inspection shows the small gear is indeed split.



Posted from Windows Phone OS 7



Edited 1 time(s). Last edit at 08/13/14 17:30 by fbe.