I have a overland brass,Rutland F2j that needs some adjusting in order to get it to run as good as is possible.It may be just a matter of shimming,moving the motor back or foward,or it may need to be repowered or have a new gear tower installed.It runs fairly good in reverse but "lurches"a little in foward.Runs fine at about 10smph.I tried a few possible cures that I recieved on this forum,but I can’t get it run any better.Any recommendations for a good shop or craftsman?
Start by checking wheel gauge on all axels to insure they are not causing a bind.
Then!
Remove or disconnect the motor/gearbox and check for binds in the side rods by rolling
the chassis back and forth on a pane of glass.
Does it have a open frame motor or can, If it’s a OF you might wi***o replace it with a good quality motor from Northwest Shortline.
Check the connection between motor and gearbox ,more than likely a piece of rubber tubing, replace! either with a piece of RC airplane fuel line or better yet Delrin universal joints (rubber/plastic tend to flex)
You also might need to disasemble the gearbox and place shim’s front and back on the worm gear. or as you say the gearbox might be needing replacement ( again NWSL) has the best.
If I think of anything else I’LL BE BAAK!
Hope this helps a bit
Good luck.
Ragnar has covered just about everything–one nice thing about brass is that it’s so mechanically simple, as compared to the newer plastic steam, that it’s pretty easy to do yourself, with time and patience. I’ve Swiss Watched my share of my own older brass. steam–some of them are almost foolproof, others take time and patience. Brass is VERY individual!
How old is the loco?
Can or Open Frame motor?
Tubing or universal connection from motor to the gearbox?
How much ‘play’ in the gearbox? Tight? Sloppy?
Spring or un-sprung main drivers? (believe it or not, it has a LOT to do with smooth running–unsprung drivers can be very sensitive to variations in the track, especially on smaller locomotives).
Is the boiler weight balanced over the drivers? Or is the weight more toward the front or back of the loco? On a 4-6-0, the balance should ideally be between the first and second set of drivers.
Frankly, not having much info on the loco right now, it sounds as if your ‘lurching’ might be from an Open Frame motor and a rubber tubing connection to the gearbox. If so, I’d take the little devil down to your LHS, see what size NWSL can would fit into the firebox, grab some NWSL Universals that fit both your motor and gearbox shafts (usually 2.5 to 3.0 MM on most models I’ve worked on), silicone putty-mount your new can motor into the frame–which means screwing or soldering a new lead from the motor to your loco frame), fine-tune the universals while the putty is drying (it remains flexible for about an hour, sets up overnight), install some Tomar track sliders, one on the + pickup side of the loco and another on the opposite + side of the tender (they come with instructions) and you shold have a smooth running loco. And if you’re into DCC, you’ve already isolated the new motor from the frame, so installing a decoder shouldn’t be too much of a problem at all. Most ‘lurching’ I’ve found is due to older open-frame motors and rubber tubing connections to the gearbox. Ove
As already said, it starts with the motor. If it’s not smooth, nothing will be. So make sure the motor is as smooth as YOU want it to be. If you do not care about impressing anyone with glass smooth running at a scale 1.2 miles per hour, that’s fine; it’s YOUR locomotive.
I have a somewhat different view from many on universals and gears. I believe if the angles and alignment are not too great that tubing is actually much better than the extremely simple universals usually employed in this hobby. And lets face it, little brass dogbones are real , REAL low tech. Two such universals ONLY make for an overall constant velocity connection when the motor and gearbox shafts are exactly parallel, and the shaft between the dogbones is constantly varying in speed in any event. Tubing makes for a cheap constant velocity universal joint. At the torque values we are talking here, as long as it has decent heft axial flex shouldn’t happen.
Shimming the worm to limit thrust float is very beneficial to long term even wear and smooth reversals, but has little to do with smooth running in one direction, everything else being equal and as long as there are no gear to box interferences. Getting the gear engagement depth just right can be a really difficult task but one that can greatly affect smooth running. Depending on the construction, how one does this can vary all over the map. A lot of really high quality brass models have the little two screw worm gearbox bottom cover that holds things together, and even though the clearance can run from 0.001" to 0.051" (that’s what I remember seeing), it it’s smooth I wouldn’t tend to fool with it because of the difficulty of changing it in a manner that will give you a correct AND repeatable engagement.
Moving to the wheels: checking by rolling on glass is a great tool. If that is smooth, don’t forget to also roll it on track laid on the glass or other flat surface at the tightest radius you ever plan to run, and don’t forget to check it going both
Most of this is beyond my modeling skills,time,and fear of screwing something up,that’s why I wanted to find someone with the skills and experience to take a shot at it.It does have a can motor and fuel line connecting the motor to the gearbox.Somewhere along the line the main crank pin was soldered(I would guess that the set screw kept comming loose).The drivers are sprung,but i noticed that the rear driversare a little light on the tracks.That may be why it runs better in reverse than foward?
It is not unusual for the crank to be soldered to the pin, because it can be made to look more realistic than a bolted connection. The whole thing will still unscrew from the driver.
One more thing, on Canon can motors the “Timing” was adjustable because of the way they were made. I do not believe it was an intentional feature. Where it was set, as well as how many poles the motor had, had a large effect on smoothness.
I do not know if they work on brass or not, but they do sell it, and they definitely do have what I would call a highly qualified model locomotive mechanic (a term I do not bestow even semi-lightly), so I would suggest you give Golf Manor Hobbies in Cincinnati a call.
http://www.golfmanorhobbies.com
There may be a lot of people around who will work on models, but the percentage that are qualified is debatable.