Problems building OO gauge white metal wagon kits.

[brian777999]

1. I have a few OO gauge white metal wagon kits which I am trying to build but some of the parts are bent. When I tried to straighten them with pliers, they snapped. I thought white metal would be a bit softer and more pliable. How should I straighten the bent parts so as not to damage them?

 

2. The ABS GWR mite/twin bolster wagon kit : The instruction on these kits is sadly lacking and there are no drawings or diagrams. There are two large cylindrical parts hanging from underneath each of the buffer beams. I thought they might have been sprue but now I think that they are supposed to be there. Does anybody have a photo of a completed model or can you explain what they are ? I have not seen them on other wagons I have built.

[kevinlms]

I Believe they could be there for mounting couplers on, typically for the old Hornby Dublo ones.

 

Kevin Martin

[Adam]

1. This is relatively common and I certainly wouldn't recommend pliers - gentle pressure with fingers usually suffices. Submersion in hot water first might help (as it does with resin components for example). Actually the cracking suggests that the whitemetal is of reasonable quality: the softer stuff, with a higher lead content, will bend very easily which is not what we, as modellers want. This is obvious when you know that whitemetal is still used for bearing surfaces in a railway context (in preservation rather than the mainline!).

 

2. ABS instructions do rather assume some familiarity with the prototype I'm afraid (not that there are usually many parts). The bits you refer to are a hint at the age of the kit: they are intended as mounting points for Tri-ang couplings. Unless you intend using these you can safely saw them off.

 

Hope this helps

 

Adam

 

Cross-posted with Kevin!

[Kenton]

Adam is correct - heat is the answer to most distorted white metal bends - but not all. Never apply too much force at best the casting will be damaged at worst - well you have already found out. The water temperature tends to have to be far too hot to soften and to be able to hold in your fingers. My experience has always been that white metal is pretty heat resistant (I use a non-temperature controlled 25W iron for soldering and am yet to mel anything of substantial size)

 

It will of course depend on the size of the part and the nature of the original white metal - some kits were made with some pretty ropy stuff and seem to start out with tiny cracks and fractures. If it is a new kit and parts are bent I'd send them back as these days (and in the past really) there is no excuse. The manufacturer should be re-using badly cast parts as scrap, not selling them.

 

To flatten wagon sides I use a wooden clamp (two pieces of soft wood as a sandwich in metal G clamps) place in pan of boiling water allow to get hot then gradually tighten clamps until flat. With smaller items it is a case of forceps and tweezers and gentle pressure while still hot. Very much trial and error.

 

Oh, and I have been known to resort to a microbunsen flame/butane solder torch (the same one I use to disassemble badly botched ebay productions brass kits) However success is never consistent with white metal - many ending up as the expected blob. Some large items like loco tank sides seem to take this heat well - very much a last resort though before binning it.

 

I guess if I had one I would use a temperature controlled oil bath - but even then unless you know the melting or more correctly softening temp of that particular batch of white metal it would still be hit and miss.

[ozzyo]

I guess if I had one I would use a temperature controlled oil bath - but even then unless you know the melting or more correctly softening temp of that particular batch of white metal it would still be hit and miss.

 

Hello Kento, alll,

 

we may have something that could be used as Kento sugests in the kitchen. That is a deep fat fryer if it has a good temp. control, but I would not like to start cooking my chips in it after cooking W/M in it.

 

So the next question would be what sort of oil? Mineral oil or veg. oil and then how to clean it all off.

 

It's all just a thought,

 

OzzyO.

[Guest dilbert]

The missus has our old small portable oven that is still in use many years later for her hobby only and that is "baking" her silicon polymer creations. The thermostat control is excellent and with silicon polymers this is important at relatively low temperatures.... dilbert

[Kenton]

Great ideas - w/m melts at anything between 150 and 400 'C (even that is an OTOMH approximation) and as said above depends on many factors not least the mass of the item. Remembering that we do not want to melt - only soften slightly so if I were experimenting it would be starting with 100'C as I can get that with boiling water and move upwards in small steps.

 

The problem with the experiment is that the item will probably either break or go too soft before you get a definitive answer and is probably different with the next item.

 

Also remember 100'C is HOT and certainly not the place for dipping fingers in or splashing around - boiling oil is probably far more dangerous which, I guess, is why it was used as a weapon during the middle ages.

 

The real answer is send a bent item back to the supplier if possible.

[brian777999]

The real answer is send a bent item back to the supplier if possible.

 

No, I live in Australia so sending anything back is not an option. I will try some of the ideas suggested here such as immersing it in boiling water and trying to soften the metal before straightening it.

[Skaran]

_{I have found using hot water - leave the object immersed for some minutes, worked on some bent w/m loco parts I had/ Repeated soakings may be needed, be gentle and take care not to scold yourself with either the hot water or the now hot w/m.}

[brian777999]

Fitting wheels to 4mm white metal wagon kits : with plastic kits and perhaps even brass, the axles boxes can be sprung apart slightly to accept the wheels once the kit is built. But this cannot be done with white metal. Do you build the white metal kits with the wheels in place and paint around them later ?

[jwealleans]

Yes, in a word. Alternatively, use brass W irons and adapt the kit to suit. I did that on the last pair of vans I built. Another D & S one I restored, I used Bill Bedford sprung W irons and the running was transformed. Sprung ones require slightly less clearance than rocking so they can be a better alternative.

 

You usually need at least three hands to assemble the wheels into a whitemetal wagon, so the brass option avoids that as well.

[pete_mcfarlane]

I struggle to assemble whitemetal wagons completely square, so I normally use an MJT inside bearing compensation unit on one of the axles. This avoids any problems with hamfisted assembly. 

[soony]

Try assembling it on a sheet of glass, I use an old microwave door glass with diagrams and instructions underneath. A few "square" blocks of metal or even very hard wood also help keeping things upright.

[jwealleans]

Has anyone else tried one of these?  It isn't the answer to everything, but I find it helps a great deal.

 

 

Coffman clamp or Right Clamp.  Not sure where you get them from now, mine was from Finney and Smith who have ceased trading.

[Nelson Jackson]

Coffman clamp or Right Clamp.  Not sure where you get them from now, mine was from Finney and Smith who have ceased trading.

I got the exact same one from mainly trains last year, although I would advise contacting them to check availability.

[brian777999]

I often soak brass in citric acid or white vinegar to get it nice and clean prior to soldering. Does this work on white metal as well ?

 

Those corner clamps are available from Micromark in the US if nobody in the UK has them.

[PenrithBeacon]

http://coffmaneng.com/

[Kenton]

 

Has anyone else tried one of these?

 

Yes, one of many gadgets used on a regular basis. The foam is not that resistant to high temperatures and I have replaced with thick card. It really is best for use in plastic kit construction. I use a metal plate with square magnets to hold brass at right angles for soldering.

 

Also, these are quite usefull for setting things square.

[gwrrob]

Has anyone else tried one of these?  It isn't the answer to everything, but I find it helps a great deal.

 

 

Coffman clamp or Right Clamp.  Not sure where you get them from now, mine was from Finney and Smith who have ceased trading.

What size is this clamp please as I see Branchlines have a stand at Warley.

[bertiedog]

Be careful with re-heating whitemetal, it does not really respond much as the re-melt temperature rises after setting, and you would have to be near the original melt point to allow the metal to anneal to soften it. Most heaters in domestic use are thermostatically controlled in bursts of heat and average it out for cooking, so the temp could exceed the aimed for value.

 

I haver never experienced white metal that could not be bent or shaped gently to correct the shape, but not with pliers or vices, but wood clips and finger pressure is all that is needed. White metal by it's nature is not a hardening metal, it remains soft, but can develop a skin of harder grade by surface hardening by pressure from the shaft.

 

Cast kits face no such strain, so should be soft all the way through.....unless the caster fiddled with the content by adding old metal, extra tin or lead etc, or adding bismuth to lower the melt.

 

If the kit is cast in pewter grade, then brittleness can be a problem, it is stronger but gives with a snap due to higher zinc content. but few makers use pewter even now, apart from DJH.

 

Stephen

[Prometheus]

The reported issue at the head of the thread is a very common problem with many K's products, particularly their coach kits, where distortions can occur through many planes. I have always found that gentle but persistent finger pressure has solved the problem sufficiently for the model to be built and sit square.

 

Trying to 'open' their GWR white metal bogies, once built if soldered, to replace wheels is another matter altogether. They always seem to snap. Epoxy glue usually comes to the rescue but the mend can be tricky and a completely square reassembly isn't always possible.

 

The joys of vintage white metal kit building !

 

Tony