Con-Cor 4-6-4 modification

[nickelplate759]

I have a Concor/China 4-6-4 (no flywheel).
I need to remove the drivers to paint them.  I already pulled one, and it's awfully hard to get it back in the right position so that the side rods don't bind (so far I haven't succeeded).  I need to pull all three (at the same time) and paint them.  I'd appreciate tips on how to manage getting them back in place properly aligned.

George

(renamed thread to better reflect topic)

[mmagliaro]

Of all the engines that have rods and gears, that ConCor 4-6-4 is probably one of the easiest to get back together right.  That's the good news.  I don't mean to make light of your problem.  It doesn't work, and that's the bad news.

First, the axles on that engine have square keys ends so that the wheels can only go on in 4 possible positions.
Start with one geared axle.  Put a driver on the left side of the axle and install it into the frame so that the crankhole is
at the dead bottom (6 o'clock, when the engine is right-side up, or 12 o'clock if you have it lying upside down in a cradle).  Now, put the driver on the opposite side so that the crank hole is rotated 90 degrees clockwise, which means 9 o'clock right-side up or 3 o'clock upside down).

You should be able to repeat this process with all 3 drivers, so that when you are done, all the crankholes on the left are at the dead bottom, and all the crankholes on the right are at 9 o'clock.

Then put the rods back on.

There are many ways to do this.  This is one straightforward way that I could figure out how to describe in
a forum post.  I think the reason quartering is so darn confusing is that it is basic, yet very hard to somehow put into words. 

[nickelplate759]

Thanks Max - but I think I described the wrong problem

The wheels are still on the axles, but the axles have been removed from the chassis.  The challenge I'm having  is getting the drivers aligned identically while the gears are meshed.  I can get the gears to mesh, but then I can't turn the driver to make it match the one next to it.

George

[victor miranda]

... I didn't think it was possible to get it wrong....

I set the  drivers in place  first.
then I align the middle driver(#2) to the last driver (#3)
then the first driver (#1)

I align by lifting the driver until it just clears the gear teeth
often I go one tooth at a time.

it is not hard once you have done it one time...

now I have to go look.... I can't remember if the drivers are left and right symmetrical.

victor

[nickelplate759]

If there's a way something can be put together wrong, I'll find it.

Thanks both of you - I'll let you know how it goes!

George.

[mmagliaro]

If there's a way something can be put together wrong, I'll find it.

Thanks both of you - I'll let you know how it goes!

George.

Ha!  Now I see.  Yes, Victor's description hits the nail on the head.  Get one driver in.
Then when you put another one in, you will find that you can always lift it out just enough so
the gear teeth clear and you can rotate it one tooth and drop it back in, until you get it to drop back
in and roll against the gear teeth so it "lands" at the bottom and the crank holes are lined up.

Good luck.

[sizemore]

It also helps if you give it a little "English", like a scooping motion when trying to get it back in "time". Like Victor and Max said once you get the hang of it, its really easy.

The S.

[strummer]

I had this issue once with a Trix K4. It got to the point where I ended up mailing it to someone here on this Forum who was able to put everything back in its place. Not naming names, in case he doesn't want this kind of info to get out...

Mark in Oregon

[nickelplate759]

Now that I have it apart, I see an issue that might (or not) contribute to the rough running I observed - at least two axles are cracked.

The driver wheels press into axle tubes (that have gears on them), and at least two tubes are cracked where the driver presses in.  The gears themselves seem OK.  At least, as Max indicated, quartering is a no-brainer since the axels are square on the end.

Any suggestions on how to repair?

George

[victor miranda]

!

I have never seen cracks there except one that was dropped.

as with most times,  new parts are the easiest solution.

like other cracked things... the gs-4 for example,
can you fit a collar over the cracked axle?

victor

[mmagliaro]

Have never repaired one and since they are Delrin, you can't glue or otherwise repair them.
Victor's idea of using a collar like he did on the GS4 drivers might work.   

I have seen some with cracks, and usually they just work anyway since the square drivers fit into them and
they don't slip anyway.   If the drivers are so loose on the axles that they just fall off, then replacement axles
are the way to go.

[nickelplate759]

The cracks are on all 3 axles (I can see that now that I've pulled them all).  They are all in the same place, and none have progressed into the actual gear.   I'm going to see if I can make a collar, but if not I'll just leave it alone for now (after I paint the drivers) and look for replacement axles.  As Max said, it isn't stopping the wheels and gears from working.  In the meantime, maybe some Loctite green to keep the drivers from falling off.

George

[victor miranda]

I begin to see....
rising out of the steamy mist...

the cracks are not a problem until the drivers fall off.
please don't use a glue to hold them, the glue will make the cracks worse.

buuuuuuut.... the cracks may mean the axles were reassembled.

and that may be the gearing/alignment issue explained.
this means there are 4 places a driver can be relative to the gear.

I doubt they are completely symetrical.
so find a dot or mold line on the gear and make sure you have the cranks
and dots/lines on the gears all the same.

alignment nirvana awaits
driver staying on nirvana may require more effort.

v falling asleep miranda


when

[mmagliaro]

The cracks are on all 3 axles (I can see that now that I've pulled them all).  They are all in the same place, and none have progressed into the actual gear.   I'm going to see if I can make a collar, but if not I'll just leave it alone for now (after I paint the drivers) and look for replacement axles.  As Max said, it isn't stopping the wheels and gears from working.  In the meantime, maybe some Loctite green to keep the drivers from falling off.

George

I wouldn't use the green loctite on these.  It's all slippery plastic and it won't work, and as Victor cautions,
it may make the problem worse.  I suppose you could put a little Walthers Goo in there.  That stuff can stick
pretty well to slippery plastics if all you need it to do is keep things from popping apart.   After a couple of days, when it really sets up, it makes pretty darn strong bonds.  But be careful not to get any near the bearings!

[glakedylan]

just floating an idea for feedback sake

what if these were spun like a bobber on sewing machine
when it is being threaded

and thread with CA being wrapped around to seal and support
where cracked

is there room enough for such a fix
would it in fact work as a fix
inn my mind it seems theoretically like a possibility
but then I confess I have more time and experience in tailoring than MR'ing

nonetheless....just an idea and wondering if possible
sincerely--