My new Gibson wheels

Model and prototype rolling stock, locos, multiple units etc.
David Thorpe

My new Gibson wheels

Postby David Thorpe » Fri May 14, 2021 11:25 am

In the past I have sometimes had problems with severe rusting on Gibson wheels. This is not universal - on most locos they're fine, but on some they're not. Most recently one of my locos has been particularly troublesome and I have cleaned, recleaned and rerecleaned the rust off ad infinitum until I have at last got fed up, removed the wheels and bought a new set. They're sitting on my desk, brand new in their packaging.

So what now? I don't know why some of my previous wheels have rusted, while others (the majority) have not. All my locos are kept in the same heated room and I do suspect that the rusting is most likely down to me - sweaty fingers, perhaps, maybe some flux in too close attendance, or whatever. In any event, I don't want it happen with the new set. (I should add that I don't think that my fingers are any more sweaty than those of Mr Average)

So I have a choice. Easiest (in a P4 context), I can just fit the wheels as they are. This may involve sweaty fingers (I can't get on with latex gloves for something like this). It shouldn't involve any flux, but if I'm having to solder on some pickups in close proximity to the wheels, who knows - it's not as though you can wash down a completed chassis. Alternatively, I understand that wheel blackening avoids subsequent rusting, and so I could dump the wheels in the ultrasonic bath, then into blackening solution, then rinse and polish them, then fit them, but all the time worried that blackening may in fact interfere, if only to a small extent, with electrical conductivity (though not nearly as much as rust does!).

Any advice would be appreciated.

DT

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Tim V
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Re: My new Gibson wheels

Postby Tim V » Fri May 14, 2021 11:47 am

I have never experienced this rusting with Gibson wheels. I have found it with Exactoscale wheels in the old days - they came with a piece of VPI paper - one should be suspicious ...

Why are you soldering near wheels? I always build so that the wheels can be easily dropped out, and now you have a scrap set of wheels you could use those to position pickups (how last century ...) before putting the proper set in. If the chassis has been designed for the wheels to be captive that is a sign of poor forethought.

I would not recommend blackening - Studiolith drivers came blackened - it was quite a job to remove the coating to get a good pickup.

That scrap set of wheels - you could get a set of new rims from Gibson and maybe rescue them? Suggest pulling off the rims first (early Gibsons made a habit of falling off) - you have nothing to lose ...
Tim V
(Not all railways in Somerset went to Dorset)

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Guy Rixon
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Re: My new Gibson wheels

Postby Guy Rixon » Fri May 14, 2021 2:40 pm

If the rust always comes back after cleaning then it's probably not due to flux, as you won't be fluxing up the wheels on a finished loco. If it only happens on certain sets of wheels then it's probably not skin secretions (unless there are certain locos that you like to cuddle).

I suspect that the kind of steel used varies between batches of wheels. There's an amazing variety of steel grades, and most of the grades select mechanical properties, not chemical properties. Further, IIUC most steel made nowadays is mostly from scrap metal, so the exact composition of the cheaper metal is a lottery. I would expect that the steel for the Gibson tyres is selected by hardness, and to be free-turning, and to be very cheap, since Gibson wheels are the economy end of the market. It could have anything in it, and once in a while it's the kind of metal that rusts most easily.

Reagrding pickups, soldering thereof, surely this is the one place to use non-corrosive flux, like Carr's Red? Or even (gasp) flux-cored solder with no liquid flux?

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Will L
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Re: My new Gibson wheels

Postby Will L » Fri May 14, 2021 3:31 pm

David Thorpe wrote:...it's not as though you can wash down a completed chassis....
Can't you? Is it not possible to remove the motor? The rest of it, preferable but not necessarily, in its component parts, will go in an ultrasonic bath. Firstly with a very mildly alkali wash (I go for a few grains of dishwasher power) then again in pure water.

davebradwell
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Re: My new Gibson wheels

Postby davebradwell » Fri May 14, 2021 3:32 pm

Just because steel is made from scrap doesn't mean it is scrap. It's still made to distinct grades according to the appropriate standard.

Back to the original wheels rusting, if steel is splashed with acid flux, isn't it necessary to neutralise the contamination or it keeps coming back? I'm no chemist but remember this tale from way back. I only let my acid flux out in emergencies and there hasn't been one for years - I just can't stand everything feelong horrible. Certainly it shouldn't come anywhere near anything electrical, like pick-ups.

There are rare individuals with "acid fingers" and their prescence in workshops is marked by a trail of gritty feeling chucks and the like. It seems to be a permanent condition so you'd know if you were afflicted.

A tiny amount of oil on the track should coat the tyres and may well discourage further trouble. Improves pick-up too.

DaveB

Jeremy Suter
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Re: My new Gibson wheels

Postby Jeremy Suter » Fri May 14, 2021 5:09 pm

Hi David
I have had a similar problem with rusting loco wheels while building, and after painting. This was due to the Acid Flux and it carried on for a while after painting.
I found that cleaning and running it for a long time at a show solved the problem. I always put it down to passing a current through the tyres and allot of use was the cure rather than the cleaning I have never had the problem since. That was at least 25 years ago.
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Philip Hall
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Re: My new Gibson wheels

Postby Philip Hall » Fri May 14, 2021 6:43 pm

The only time I had a problem with Alan Gibson tyres rusting was when I had used an etch marker pen to blacken them, and not neutralised it properly. I now only blacken the face of the tyres with Birchwood Casey Superblue, applied sparingly with a cotton bud, and well washed off afterwards. With this method I have not had any further problems. I still use the etch marker pen on Ultrascale wheels, neutralised well as above, and again, no problems. Unfortunately, the etch pens are now getting horrendously expensive.

I still do solder close to wheels for the likes of pickups etc., using a paste flux, and I occasionally don't bother to have wheels on a chassis that drop out. I solder the brakes in place and bend them gently out of the way when fitting the wheels. I like Guy Williams' notion that if it's all fitted properly in the first place it shouldn't need taking apart for twenty years or so, and I'm getting to that time of life when that sort of span seems a reasonable idea. However, I would be the first to acknowledge RTR engines with drop out wheelsets are much easier to set up!

Philip

David Thorpe

Re: My new Gibson wheels

Postby David Thorpe » Sat May 15, 2021 3:46 pm

Unfortunately in the locos I build at least one set of driving wheels (the motorised ones) tend not to be drop out and while the others can be dropped out it's usually difficult putting them back again. However it can be done. Also I'm afraid that I fit, by which I mean solder in place, both pickups and brakes after the drivers are finally in position and running freely. I'm not really sure how I'd do otherwise.

I hate pickups. In fact, looking at a loco kit as a whole, the most difficult and tedious part of the whole build tends to be pickups - first finding and constructing somewhere to put them, then making them, then fitting and wiring them. Kit manufacturers tend not to help as all too often (in my experience) the subject of pickups is glossed over in the instructions ("now fit your pickups of choice", or something like that assuming they're even mentioned at all), and there's no specific place for them on the chassis unless, of course, plunger pickups are provided and I don't really like them. Now if at the next Scaleforum someone would like to demonstrate successful ways of making pickups I shall be first in the queue.

So before every loco build I decide to use split axles. Buty it seldom works out like that as the chassis/split axle/gearbox combination usually proves very split axle unfriendly, and I end up with the dreaded pickups again. At least I usually build the tenders of my locos with split axle pickups and while that can be quite adequate for the whole loco it's not much good if you're building a tank engine!

Anyway, thanks for your answers everyone. For my current build I shall dry my hands, ignore blackening, and use Red label flux for any soldering. Hopefully the wheels will then remain pristine.

DT

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Will L
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Re: My new Gibson wheels

Postby Will L » Sat May 15, 2021 10:04 pm

David Thorpe wrote:...I hate pickups. In fact, looking at a loco kit as a whole, the most difficult and tedious part of the whole build tends to be pickups - first finding and constructing somewhere to put them, then making them, then fitting and wiring them. Kit manufacturers tend not to help as all too often (in my experience) the subject of pickups is glossed over in the instructions ("now fit your pickups of choice", or something like that assuming they're even mentioned at all), and there's no specific place for them on the chassis unless, of course, plunger pickups are provided and I don't really like them. Now if at the next Scaleforum someone would like to demonstrate successful ways of making pickups I shall be first in the queue.

You should have asked last time I was there. However I have written up my methods of doing pickups.
While we are there I did a bit on making removable break gear to.

So before every loco build I decide to use split axles.
Frankly I think they are just as much of a faff what with having to manufacture axles, and avoiding stray shorts through the bodywork. Either way you have techniques to learn, once you've got them they become second nature and no a problem.

Philip Hall
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Re: My new Gibson wheels

Postby Philip Hall » Sat May 15, 2021 11:18 pm

My method of pickups is usually using 0.3mm hard brass wire wound into two or three coils as Will has done in his picture. However, I differ in their mounting by having two longitudinal bus bars along the chassis to which these coils are soldered, with the wire bearing on the edge of the flange. They are a bit fiddly to fit but once set seem to stay set.

The great advantage is for wheel cleaning as the back of the flange is not used. I just lay a length of non fluffy cloth over the track, dowse it with cleaning fluid and run a set of wheels on the cloth until it stays clean. The cloth cleans the tyre surface and the pickup point in one go.

However, with conversions I am often stuck with what is provided, usually phosphor bronze wipers, which can be either light in pressure (Hornby Terrier and many of their tenders) or very stiff (most Bachmann). With these I always try and arrange extra pickup on tenders if it isn’t already provided. I have been known to go to extremes and add light pickups on pony trucks as well. Mind you, Hornby do that all the time (T9, M7, Schools etc.!)

Philip

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pete_mcfarlane
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Re: My new Gibson wheels

Postby pete_mcfarlane » Sun May 16, 2021 11:26 am

Just before the range changed owners (about 15 years ago) I stocked up on Gibson wheels for some kits I have to build. I still haven't built all of them, so there's a stash of unopened wheels sitting in a box.

All are fine, except for the 3 packs of Terrier wheels which are covered in surface rust. So something in the manufacturing process for those particular wheels has made them rust.

davebradwell
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Re: My new Gibson wheels

Postby davebradwell » Sun May 16, 2021 5:06 pm

It would seem, David, as if you have yet to discover the wonders of the keeper plate to which you attach everything- dummy springs, brakes, ashpan, pick-ups and which solves a number of problems at a stroke. First it sounds like you have to go through the trauma of abandoning the fixed axle, though, to give you more to keep.

Steel tyres will be turned while being sprayed with coolant/lubricant and will subsequently be degreased to a greater or lesser degree - a possible cause of variation of rust resistance. Also surface finish can play a part in how quickly something will rust.

DaveB

Philip Hall
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Re: My new Gibson wheels

Postby Philip Hall » Sun May 16, 2021 10:20 pm

Dave's mention of surface finish prompts me to say that I always polish tyres with a rubber abrasive wheel in a mini-drill after painting which brings the treads up a treat. They always look a little bit smoother afterwards and I am convinced they tend to stay cleaner as a result.

Philip


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