At least you were progressing in the right direction.
If mark doesn't give up on things, there is always hope that he can
traverse the same general learning curve and become one of us 'old
farts' that answers questions too.
No, guy, I check voltages with one of my multimeters. If you read what I
wrote, I was talking about trying to light the headlight bulb, by itself,
with a 9v battery, so I'd have a constant intensity.
Honest, guys, I wouldn't have gotten this far if I didn't have a clue. Let's
see, I think it might be getting some pickup on the trailing truck, and it
gets it off the two drivers. The leading truck has, I think, plastic
All I'm trying to insulate is the side that supposed to be insulated by the
two insulated driving wheels and the insulated trailing truck. Where I
soldered the wire that goes to the tender for the other side, it may stick
out a bit, which is why I was insulating the body from that. I also noted
that if the drivers have some sideways play, as they need to, the insulated
wheels' conducting tires contact the frame, which is why I put the plastic
there. I'm also seeing play in the tender wheels, so that they sometimes
contact the frame; ditto with the insulated trailing truck.
Have I now covered everything that I've covered? <g>
Right, and if I'd had the insulated wheels mixed up, it wouldn't run at all,
and I'd have the breaker in the power supply popping all the time, not just
Yup, runs nicely. Starts and stops as I touch the wire to the other track.
Yes. Esp. after the 52nd time I took it apart, this time to trim the wire
that comes out of the crosshead, and the casting, which seem to be slightly
longer that the one from 45 years ago, and were butting up against the
cylinder every rotation. Now it's smooth.
Found that out. One washer, in the cast indentation, so that it's about
level with the top of the rest of the frame, and it seems right - I can
spin the motor with a finger, and the wheels rotate without binding. A
second washer, btw, lets the motor spin all it wants... above the worm.
With only four drivers, you don't NEED side play. In any event, the
driver tires should not touch the frame, with or without side play. Same
with the trailing truck wheels. The wheel hubs should be raised enough
that they touch the frames before the wheel rims even get close to
Are you missing some washers that should fit between the hub and frame,
inside the wheels for drivers, and outside for trailing truck?
We're talking about a mm or two, here, I s'pose I could file it.
Hmmm... maybe adjusting them on the axle might help with fitting the track.
The tender - the wheels keep jumping the track (and it's code 100, btw).
Can't really put any inside the drivers - they were supposed to be
permanently on, and I had to pull one (on the axle w/ the gear) and use
Loc-Tite on it, so there's no way for that. I could try washers on the
trailing truck, or, as I noted above, seeing if I can just push them
further onto the axle.
Thanks. Right now, I'm still pushing the thing. I've got it on a curve
(getting the tracks up will take a *while*, esp. since I have to put covers
over to keep the large cats off <g>), and I note that if I push on the side
of the engine that does not have the insulated wheels, it moves a bit
easier. I've tried tightening and loosening the plate under the axles, so
any other ideas?
At this point, I'd say your 'trouble shooting' has covered most of what
I can think of. The only other thing would be excessive wear of he axles
in the frame. This would be allowing the worm gear to mesh too tightly
with the worm. (making for VERY touchy adjustment.)
Great. And given that it came "partly assembled", which in this case meant
the drivers and leading truck were on, and almost nothing else, I'm
thinking that this was an estate sale of stuff from someone's late parent
that had never been run, so worn shouldn't come into play.
I've not had time to follow this thread properly.
1) remove the motor and gently push the chassis/mechanisim/frame along
the track, feeling for binds. Fix the binds.
2) install the motor, block up the chassis and apply power directly to
the brushes. Reduce the voltage until it either slows to a smooth halt
or binds. Fix the binds.
3) turn it over (onto blocks) and apply power to the wheels which have
pickups. Sequence (say) left front + right front, left front + right
second etc until you've covered every combination. That will show up any
4) Now try it on the track, without body. It should run nicely. If not
there's something wrong. Post description here.
5) replace the body with screws. If running is different to 4) then
something is touching inside the body.
I follow your reasoning, and would come to the same conclusion!
So --- Back to the beginning ---
Take the bare frame, drop the two driver sets into the axle slots,
attach the cover plate on the bottom, and make sure there are NO
problems rolling along the track (NO side rods at this time, no leading
or trailing trucks).
IF there are any rough spots, holler, we'll think of things to check/
adjust. It needs to be free enough to roll down the track, by itself,
with NO pushing, if you raise one end of a 3' section of track a couple
of inches. (A single inch would be best, but lets start with an easier
Same aim --- free rolling on a SLIGHT incline.
Someplace along here you need to check the drive gear for roundness.
This is an 'eyeball' check --- to be done with the frame UPSIDE DOWN, so
that the axle is riding in the same place it will be when things are
assembled and running properly. You don't have to stand on your head and
look at the gear where the worm will be riding, any 'out of round'
condition will be visable watching the bottom side. [I don't expect
there to be a problem here, but now is he time to check.]
Next add side rods (cylinders & main rods are the next step --- you
already mentioned curing a problem with the cylinder rod on one side.)
Re check for free rolling [This is where I would expect to find a
problem. the driver that has been 'off the axle' may NOT be exactly
quartered any more.]
If this is where the problem rears it's head, there ARE 'shade tree'
fixes that will allow you to get the thing running 'sorta', to be able
to make a decision later as to whether or not you want to invest the $
to do a proper fix of the quartering problem.
Note No leading , trailing trucks, no motor to this point.
Let us know results to this point.
One other check that you should do along here someplace.
Frame upside down, drop the drivers in their slots, (easiest if you have
TWO straight edges) lay a straight edge on the tires of the drivers on
one side of the loco. straight edge on the other side of the loco, how
do they compare??? They SHOULD be visibly parallel, IF the frame is
'Tweaked' /bent, you will be able to notice the difference in the lack
of parallelism for the two straight edges.
IF that shows up, it MAY be fixable with some gentle 'tweaking' of
things. (Be aware that the ZAMAC frame is liable to be on the brittle
side. So don't just grab hold and start twisting.)
Ok, someone asked me to take it apart *again*, so since I did ask for help,
I took the motor and the trailing truck off, and tried that. The results
* if I push down a little, and run it along the rails, it seems to go ok.
* sliding it down a tilted track, the drivers don't turn
* if I hold it in my hands, and turn the gear, it seems to bind
in one direction; if I push front and rear drivers, it seems
to be ok.
It does need to be free enough to 'Roll' down an incline track.
I presume your recent test was with the 'cylinders. main rods, and side
rods still attached.
Try removing them, and see if 'just the drivers & axles will roll freely.
IF 'just the wheels' shows up as having a problem, the first thing I
would check for, is if your 'locktite/ crazy glue' joint may have a
'fillet' of glue on the back side of that particular driver, interfering
with the smooth rotation of that driver set. [If it does, a sharp razor
blade' will handle removal of the excess glue.]
The binding in one direction when you turn the gear suggests that one
driver is slightly out of quarter. Just enough so that the slop in the
siderod bearings isn't enough when turning one way, but is enough when
turning the other. The siderods displace forward/backward when driven by
the geared driver.
That sounds like either the wheel wipers are sprung against the drivers
too hard or something in the valve gear / coupling rods / connecting
rods is tight.
Different action in different directions probably means that the piston
rods are sticking / wheel out of quarter / coupling rods of different
Definitely something wrong. ;-)
Is the hang-up/restriction continuous or just for part of a turn of the
If it's continuous the restriction is in the wheel wipers (assuming it
has them) or in the axle bearings.
If the restriction is for part of a turn only, and for the same part of
the turn, then the problem is in the piston/valve
gear/connecting/coupling rod area.
You check this by:
- remove the valve gear and check wheel rotation.
- remove the connecting rods (wheel to piston) and check wheel rotation.
- remove coupling rods. (between wheels)
(remember to put the bits in a small tin or zip top bag)
(remember to look how it all goes together and where each bit goes in
relation to the others - draw a picture / photograph)
Remember, your finger is more powerful than the motor.
Neither. I *think* I've found what's hitting: the ->top<- cylinder has this
rod that comes back about a quarter or a third of an inch. the rivet that
attaches the rod that goes into the cylinder - not the piston rod, but the
one above it - anyway, that rivet seems to be hitting the cast-on piece.
Should that cast-on piece be holding the rivet beyond its end, or do I need
to file it down some?
----- * ------------------------ (radius rod)
===* <- this rivet, this cast-on piece - the = signs
Still a little resistance from the wheels - sort of like moving under oil,
rather than rolling free.
And after taking it apart for the 57th time... one of the damn microscopic
rivets popped, and I can't find the *one* spare that came with the kit, and
I'm not spending $5.50 for that. So, either I use a piece of wire, or I try
to solder a piece of wire to the head of the rivet, or maybe I'll find a
microscopic brass nail....
mark, unbelievably pissed
I avoid using rivots and prefer steel sewing pins:
1: insert pin through hole in part A
2: stick through a small piece of paper
3: insert through hole in part B and solder pin to back of same
4: snip off excess pin, tear out paper and file away any excess
solder that may be present
The paper not only functions as a spacer between the valve gear parts,
but, prevents them being soldered together. This idea is by no means
original. I believe I came across it about forty years ago in MR. HTH.
A sewing pin or a tiny brass nail should do the job.
You can put the nail in an electric drill and apply a needle file to it
to shape a replacement pin.
Remember to file to shape from the end away from the chuck and wear a
leather gardening glove so the file doesn't get pushed into your hand -
That rivet shouldn't hit ANYTHING. The "piston" of the upper part is the
"valve". It should jiggle back and forth when the lower piston (the
actual piston) reaches each end of it's travel.
Actually that rod/rivet shouldn't move very far at all, so (without
seeing it) I'm suspicious that the excentric crank , which screws to the
driving wheel, is mounted on the rong angle. (too far out)
The connecting and coupling rod screw holds the eccentric that drives
the valve gear should drive the vg at 90 degrees out from the connecting
rod/piston. Until the screw is tightened it can flop about at any angle,
but there should be a stop so it sits at 90 degrees and gives a through
some where about half the connecting rod/piston throw.
The purpose of all those levers and rods is so the valve moves back and
forth in the opposite sequence to the piston but pauses at each end of
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