Concor/Kato/Lifelike/Hudson 6-wheel tender truck upgrade

[strummer]

...and so it begins...

Mark in Oregon

[mmagliaro]

...and so it begins...

Mark in Oregon

That is exactly right, Mark!   

My main reason in trying these improvements, and especially in photographing and publishing them here, is that I hope the rest of you can help hone my idea to come to the best solution we can think of for this.

Those 6-wheel sled pickups have been a problem for a long time, and maybe, just maybe, there is a simple way to fix them.

[peteski]

The fold is a great idea!  They can do half-etch, so I just need to put an extra center section as a mirror image
that flips down on a fold over the middle.  But I still think you would want to glue it.

That's what happens when other people look at things from a different perspective. I think this is called a think tank. 

...as for the flexibility, remember, a square piece of phosphor bronze, that is .008" x .008", ought to
be about the same as a piece of .008" wire.  In fact, even if I used .015" stock, and the arms were .008 thick by .015" wide, they are only bending against the thin dimension, so it ought to be fine.

Not quite. Since the etch piece will have a more-or-less a square cross-section, it will have more metal than a circular cross-section with the same dimensions. It will probably be more equivalent to a 0.010" wire.  Still, I think it will work just fine.

[mmagliaro]

Agreed, the square-cut metal piece might be a little stiffer than the round wire.

And now... here's a different approach.  I had to completely make a set of contacts for a second truck for the other Berk I'm working on.  I came up with this.












It is running in the second Berk right now.  The pickup works great, the wheels roll well.
I did have to find some other wheelset to put into the middle position, because the one with the flanged groove on it gets in the way of the wire.  I think I ended up using some old Atlas metal wheelset.  I turned down the flanges so it was code 55 friendly.  It pops right into the sideframes and spins nicely.  It isn't a perfect match, but blackened, it looks okay.

If I had some heavier phosphor bronze strip, I would have used it instead of adding the styrene shims.  But overall, it does the job.  And I think the wire provides even better flexibility and smooth contact than my other scheme

[victor miranda]

I wish I had a little more time in the next few days...

this is a riot.

victor

[Lemosteam]

Max, cool.  The only difference I would make, is to lengthen the two outer tabs so they could be bent over to hold the assembly into the truck. That way it could not fall out if you pulled one or both axles.

[peteski]

...and round off and polish the top of the finger going up into the floor - that will greatly improve the already good electrical contact.   I polish both the fingers and the metal strip ends in my locos and that really makes them work well. Not only the contact is solid (no microscopic roughness) but whatever residue is in the metal polish prevents them from oxidizing.

The latest scheme is great but the photetched drop-in pickups would still be good for the unwashed masses. And for lazy people who do not want to build jigs or solder. 

[mmagliaro]

...and round off and polish the top of the finger going up into the floor - that will greatly improve the already good electrical contact.   I polish both the fingers and the metal strip ends in my locos and that really makes them work well. Not only the contact is solid (no microscopic roughness) but whatever residue is in the metal polish prevents them from oxidizing.

The latest scheme is great but the photetched drop-in pickups would still be good for the unwashed masses. And for lazy people who do not want to build jigs or solder. 

Actually, I did do that after I took the photos.  I polished and rounded the top with some 800 grit sandpaper.

[peteski]

I use a 4-grit fingernail polishing board and then TopBrite polishing compound with a cotton buffing wheel to get a mirror-like finish. There seems to be some residue left by TobBrite which prevents tarnishing.

[SkipGear]

Agreed, the square-cut metal piece might be a little stiffer than the round wire.

And now... here's a different approach.  I had to completely make a set of contacts for a second truck for the other Berk I'm working on.  I came up with this.












It is running in the second Berk right now.  The pickup works great, the wheels roll well.
I did have to find some other wheelset to put into the middle position, because the one with the flanged groove on it gets in the way of the wire.  I think I ended up using some old Atlas metal wheelset.  I turned down the flanges so it was code 55 friendly.  It pops right into the sideframes and spins nicely.  It isn't a perfect match, but blackened, it looks okay.

If I had some heavier phosphor bronze strip, I would have used it instead of adding the styrene shims.  But overall, it does the job.  And I think the wire provides even better flexibility and smooth contact than my other scheme

Max,
 After I saw what you were doing originally, what you came up with there was almost exactly what I was thinking of for a cleaner solution. My only difference was to make the main post a U bend in the wire instead of soldering a tab to it. Just hadn't got around to posting it.

[peteski]

Do the latest iteration of the wire pickup adapter contact the middle wheels?

[Mark5]

Max et al, thanks, this thread has given me some splendid ideas for one of my projects.

[mmagliaro]

Do the latest iteration of the wire pickup adapter contact the middle wheels?

No.  None of my schemes contact the center wheel.  I do not think it is practical to expect good contact on 3 points in a single contact.  The Kato GS4 solves the problem with an independent floating finger for the center wheel.  Unless I want to get into that, I think the center wheel contact should be left out.  I'd rather build something that makes very reliable contact on 2 wheels.  After all, we've got lots of 2-axle-truck tenders that work great, if we just make sure the contact is solid.

[victor miranda]

this is not difficult.
solder the wire into the grooves and fold over

make sure to arc the outer two and let the center tab contact the center wheel
the fact is that the center will not do much pickup in any case. in unusual circumstances it may.


one does not have to groove the  tabs for this to work
it make it easier .

I think solder will hold for a while.  eventually the solder will crack and fail.
so add a mechanical hold.

victor

[mmagliaro]

Victor,
I like the fold idea.  In fact, making just one of these at home, one could just file little notches in the strips of phosphor bronze, solder the wire into them, and then file little fold notches, fold the metal over, clip with spring tweezers, apply a little more heat, and then the wire and the two folded pieces of metal would all be neatly soldered together with the wire in a notch so it won't be able to flex and ever break the solder joint.

But I do agree with Peteski, that if I decide to actually produce an etched part, I want to make something that
pops out of a fret and drops into the truck without any home bending or soldering.