Hi, I have a love hate relationship with Hallmark. The first ever loco I got from them suffered major zinc pest rot on the wheels which caused an unfixable short and I quickly sold that engine off. Their engines tends to also have rather fragile solder joints.
This is my second Hallmark loco, a Santa Fe 2507 class 2-8-0, ex KM&O loco.
It has odd bubble in the casted wheel. At first I thought it was oil trapped below the paint, but after I stripped the paint its still there. I tried using a screwdriver to gently pry at the bubble, and indeed, it was flexible. Once I popped it, no liquid came out, so it was likely air. The casted surface also developed a copper sheen to it.
Popped a large bubble, so now the surface is flat:
My question is, should I be worried about this? Is it a sign of zinc rot? I dont believe copper is used in the mixture to make diecast, but Im no expert. Just want to make sure these wheels dont fail on me in the future.
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Also, I've never seen this kind of suspension before on a brass loco. Usually there's little springs between the frame and the bearings, but this one uses two strings of springy wire. Its rather strange, and if anyone has any tips for me that'd be great! (Like, whether the wire should be straightened, or etc.)
Thanks!
Charles
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Modeling the PRR & NYC in HO
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Trainman440 Also, I've never seen this kind of suspension before on a brass loco. Usually there's little springs between the frame and the bearings, but this one uses two strings of springy wire. Its rather strange, and if anyone has any tips for me that'd be great! (Like, whether the wire should be straightened, or etc.) Thanks! Charles
New York, Vermont & Northern Rwy. - Route of the Black Diamonds
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If it's a bubble, and it "popped" when you scraped it, it sounds like a paint bubble to me. What was the "stuff" that scraped off? Metal or paint?
Yeah, I don't get the copper color. Wheel centers were sometimes cast in brass--maybe that's what you're seeing. Other than that, I expect it would be copper plating. Don't know why, but I don't see a downside.
I see NO indication of zinc pest happening.
The springs are interesting, for sure. One thing: it'll be harder to lose them in the carpet! If they do the job, I'd leave them alone. If they don't, you could rigidify them with a strip of brass glued onto the inside of the frame. Adding coil springs looks like WORK!
Good job on the photos--very helpful!
Ed
Hi there. The bubbles seem to be a plating issue, not zinc pest. I would not worry about it as I paint my brass. As for the wire springs, is there anything wrong with them? The usual springs can be a source of frustration (ever see one of these fly in the air?).
Simon
There were a number of engines imported from one of the manufacturers' I believe it was Dong Jin who used this type of suspension and it seemed to work well. I know I have a couple of them in my set of brass steam engines.
Rick Jesionowski
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Ed- no I had already stripped the paint before I took that photo. Thanks for the spring info!
Simon - I think you nailed it! seems like someone didnt cleant the surface well enough before plating, thats my guess. and as far as the springs go, there's nothing wrong with them, I was just curious if anyone knows how to tune them. Like for ex, is the springy wire supposed to be straight? Should I wrap them around the pegs mounted on the sides of the frame? etc.
Rick - ah that explains it. Rather interesting and a novel idea by Dong Jin.
Cheers!
It's just a piece of wire with a bend in the middle that goes over the driver-axle bushing. You bend the ends to stay located over the pins, and the center of the wire pushes on the top of the bushing giving spring action. Adjusting the curve of that bend changes the 'ride height'.
If I wanted heavier spring action, I'd try to duplicate the idea with flat wire ("metal linguini") starting with the same general curvature -- lay the existing spring on a piece of paper, trace it, and bend the new wire to the same profile...
I'd expect the driver centers to be something like lost-wax castings. There is no issue in using the brass alloys for this purpose; many detail parts over the years from some well-known makers have been made that way.
Brass does contain zinc (probably at about 40%) but that does not imply it behaves like Zamak or other pressure die-casting alloys.
Trainman440 I dont believe copper is used in the mixture to make diecast, but Im no expert. Just want to make sure these wheels dont fail on me in the future.
A couple of thoughts...
1) I don't believe that is copper. A couple of my Sunset brass locomotives have brass centers in the drivers that are painted black. I would think this is what you have also.
2) If it was zinc pest, I believe you would have seen more evidence when the black paint was removed. I do not think you need to worry much about it.
Metal can be weird. If you clean copper with a wire brush in a dremel, it will start to look like brass. If you clean brass with a piece of sandpaper it can start to look like copper.
-Kevin
Living the dream.
NO that is a factory suspension that is typical of Hallmark engines from that time period. It works or can be made to work but not nearly as well as the traditional individually sprung axle bearings.
There are reasons that Hallmark locos from the 1970's and into the 1980's do not command much value on the brass market. While details may be ok, they simply were not made to the higher standards of some other importers at the time and/or do not match the standards in place at the brass builders that remain today.
Some work is generally required to make them run "well".
For these things, my philosophy is: if it's ain't broken, don't fix it. I have a lot of steam locos with no springs and they work fine. Of course, good trackwork does help!
These ARE 'individually sprung drivers' to the extent you want them individually sprung for 'suspension reasons' in a model. Note the 'half bushings' on the axle pictured, but full bushing on the pair in a different shot. These allow a certain amount of cross-equalization that i think would be difficult to 'get right' on an engine with individual coil springs; I've seen it mentioned here in several contexts that 'sprung' drivers with coils are much more about better power pickup than actual 'suspension' or equalization.
Overmod These ARE 'individually sprung drivers' to the extent you want them individually sprung for 'suspension reasons' in a model. Note the 'half bushings' on the axle pictured, but full bushing on the pair in a different shot. These allow a certain amount of cross-equalization that i think would be difficult to 'get right' on an engine with individual coil springs; I've seen it mentioned here in several contexts that 'sprung' drivers with coils are much more about better power pickup than actual 'suspension' or equalization.
Im sorry could you expand? I dont seem to get the difference between half bushings and full bushings...
Overmod--
I understand your opinion regarding the "sprung" mechanism.
There are others of the opinion the the long wire "spring" does not allow those Hallmark Models to track very well. This includes the moderator of at least one brass model group over on Facebook. Some folks have completely reworked the springing of the Hallmark Models to improve their performance, but I do not have pictures of that.
On my own layout with less than flawless trackwork, I've definitely seen the steamers that have coil sprung axles perform better than those that do not, especially on radii of 30" or less. Whether that is better power pickup or better tracking over the occasional uneven rail joint, they definitely ran better for me on all counts.
John
I dont currently own any other Hallmark models besides this 2-8-0 as of yet, but this guy runs fine on my 22" curves (and one section of 19" curve, my layout is the Virginian 4x8). I did rebend the spring wire though, in order to stiffen the front and rear drivers more than the center drivers, for better tracking.
Kalmbach keeps deleting the response, so this will be shorter than usual.
Axles on these don't run directly in bearings pressed or cut into the folded-sheet brass chassis. Instead they run in bushings, possibly made of sintered 'oilite' construction, that give a machined bearing area against the axle while being able to slide up and down in the comparatively wide slots in the chassis for suspension but not move fore or aft as they do.
Lateral spacing between the wheel hubs and chassis is made by the 'flanges' on these bushings.
I saw two types of bushing in the pictures. One, I thought on the main driver pair, was full-width on the axle. Others were split as two hat-shaped 'half bushings' which located the wheels as above but left the axle exposed in the middle. If you wanted a centered pressed-on driving gear on an axle, it would need to have the half-bushings.
Coil springs, or more pedantically helical springs, can be made to have pressure over a longer distance than the bent-wire 'leaf' spring and pivot arrangement used for the 'bendy-beam' support. The catch is that all of them have to be carefully adjusted individually to get their chassis to run straight and level when the chassis is not carefully balanced both longitudinally and transeversely, and they may show somewhat '60-Cadillac style roll when run fast in curves. What I was told years ago is that it's somewhat easier to arrange the engine to be given 'three-point suspension' -- often with careful mounting of a leading four-wheel truck and either the last driver pair or a trailing truck -- and then use long soft springs that keep the 'other' drivers in contact with the electrified rails (and float laterally if desired) without actually bearing the full weight of their part of the chassis.