Whte Metal Models
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However, I have never gone down the white metal route and was wondering if anyone ele has for trams. What is the best method of assembly an holding together. Traditionally it was solder but with modern adhesives I suspect life might be a bit easier. Bodies are £30 and BEC have a suitable chassis. Anyone any experience of white metal trams?
David
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While not trams, I've done a few white metal kits in the past using two part epoxy and superglue and it's a slow process to get good results, as the kits require a fair bit of preparation. I sill have a couple more loco kits in stock yet to build and will be trying the solder route this time, as it's quicker and they're supposed to stay stuck together longer! I will however practice with some smaller kits first and use low melt solder, as white metal kits still need a reasonable competency level and much patience to get the desired result.
It will be a good idea if you too can practice on something inexpensive to build up your confidence if you're not used to either kit building in general, or white metal kits in particular. In addition to the assembly, there can also be much preparation required prior to painting. However, with a little practice and taking plenty of time over everything, good results can be obtained.
Others here will have greater experience than me and I'm sure will offer further advice.
Good luck and chat soon,
Bill :)
Last edit: by Longchap
At 6'4'', Bill is a tall chap, then again, when horizontal he is rather long and people often used to trip over him! . . . and so a nickname was born :)
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Solder Station Weller Iron WHS40 Temperature Controlled 40W, 450°C
If you're looking for one after these have gone make sure it's the LT version, the normal WHS40 only goes down to 150C.
The only minor gripe I have with it is that the control is not calibrated in degrees, so you need to run tests with different melting point solders or a pyrometer and make your own marks.
Cheers MIKE
I'm like my avatar - a local ruin!
I'm like my avatar - a local ruin!
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No trams but plenty of white metal kits. Soldering is best, needs a low temp iron, and the correct solder and flux. I normally tack weld first (practice on some scrap pieces) then run the solder in the rest of the joint. The surfaces need to be freshly cleaned, grease-free, otherwise you will get a cold solder joint.
I use an iron with a 15-60 Watt range set at 15-20 Watts and a tinned tip, never found the need for one of those expensive temperature controlled models as it's a different technique to soldering brass. I use low residue organic flux, gets the solder flowing beautifully and no clean-up necessary.
Keep away from 2-part epoxy, make a mistake and the parts will be in paint stripper for the next month while the epoxy dissolves. As soon as you clean the metal a thin oxide coat forms, that's what the epoxy will stick to unless it's done immediately after preparing the surfaces.
5-15 second gap-filling CAA works if the parts overlap and are cleaned immediately before gluing. and is a must for the detail bits. Just don't drop it, parts will fly everywhere.
Nigel
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Superglues, in my experience, don't work too well on edge joints with white metal because of the porous nature of the metal. This results in fairly brittle joints, When buying second-hand models for rebuilding or reconstruction, this has been an advantage in that by the time the model gets to me in the post, it has become a kit of parts again … ideal for my purposes as it is a much cheaper way of obtaining the kits than buying overpriced unmade examples!
Solder is also a good method but I have never been that competent at delicate soldering with low-melt solders, although I once repaired a badly cast tender side on a K's Q1 using normal melting point solder. I built up the layers slowly a little at a time until the missing bit of the casting was all filled, then filed it back to match the profile. No one told me you can't use normal solder with white metal, so I did it!
Sometimes, a combination of all of the above may be advisable. Superglue for a quick joint where there is danger of slippage, then epoxy or solder for strength.
Jeff Lynn,
Amateur layabout, Professional Lurker, Thread hijacker extraordinaire
Amateur layabout, Professional Lurker, Thread hijacker extraordinaire
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However, I do have some experience (a little) with BEC motor bogies and don't like them !!! To me, they seem like a "blast from the past" - we've moved on from the old clunky 3 pole motor that's either "full on" or "off". Not good news for trams I fear. Try Halling of Austria. More expensive, yes, but (IMHO), light years ahead of BEC.
I'm usually disappointed by the lack of scale speed on tram layouts. Most seem to run at a scale 200 mph and catapult the poor passengers into either the back or front windows depending on whether the tram is starting off or stopping. Halling motors are far more controllable.
'Petermac
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Srman brought up the issue of porosity. If the molten metal was degassed (which it should have been but you are at the mercy of the caster) and was cast in a centrifuge porosity is not an issue, especially for slow curing CAA which likes as much surface as possible. You do need an overlapping flange which hopefully was designed in. If not solder it.
My experience with 5 minute epoxy is that the adhesion is questionable unless it is used immediately the metal is cleaned. It gets as hard as regular epoxy after a week or so anyway.
It's worthwhile enquiring what the white metal melt temperature is. It can range considerably depending on the alloy composition. I would use a big, slow rpm high torque motor and use it to drive bogies with high ratio gearing. Hollywood Foundry Lowboy is worth having a look at.
Nigel
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I did a Google for white metal melting point, evidently it can be as low as 135C up to about 350C which is why I would not like to take a chance wiyh an iron that only goes down to 150C; if possible try and find a spot on the model to test that will not be noticed or which can be easily filled if you do melt a bit. I usually fit brass buffers in place of any supplied white metal ones, so a buffer is a handy test item.
I prefer 70C lo melt solder, which is well below white metal melting point so an iron with a min 100C is fine.
Cheers MIKE
I'm like my avatar - a local ruin!
I'm like my avatar - a local ruin!
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I've had kits where my iron set at 15 Watts melted the castings (OK if tack welding) and others where 25 Watts was perfectly fine. All that white metal acts as a very efficient heat sink, the idea with the solder is to use the iron to get it to follow the flux, not to heat all the metal so that the solder melts and flows in. Hence mu use of organic flux. Adding brass bits is different, heat the brass to melt the tinned solder.
Nigel
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Metallurgy was never my best subject but I remember the diagram that showed the lowest melting point for alloys and it was very low for some. One even below boiling point of water, used at one time by plumbers to aid bending of pipes.
I think BEC bogies just use a standard model electric motor much the same as everyone else. They are significantly cheaper, at least in the UK, that some of the stuff on offer.
I would assume glues are the way to go. If they are good enough to hold planes and cars together then I suspect they are fine for a model. From the comments it looks as though simple assembly jigs and fixtures help while the glue sets.
There is a new product on the DIY market called SUGRU. basically a room temperature hardening rubber. Check out the site, sugru.com I think. I have tried it out on some models and it seems to work. It certainly works as a general repair product.
Thanks again.
David
PS further observations always welcome.
Just remembered. SUGRU application below.
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Cheers MIKE
I'm like my avatar - a local ruin!
I'm like my avatar - a local ruin!
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White metal casting is one technique I have always fancied having a go at. Taranti sell a started kit and Irish model soilder companies stuff is widely available. Cannot remember the name but many, many years ago on a motorcycle tour of Ireland we are riding down this road out in the country when a sign appears for the model soilder company. Prince August (Hoobies Catalogue) , basically a shop attached to the factory.
I do not know if general purpose 3D printers have the facility yet, but one application of 3D printing is to print complex forms with casting wax and then use the model to make a lost wax casting mould.
David
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You're a braver man than I. Just make sure you clear it with the authorities, they look askance these days on backyard foundries. Plus you'll probably need the scrubbers to limit environmental pollution from all those metals. I looked into this a few years ago, stopped after it got past 5 figures. Resin casting is a lot easier, but poses another set of environmental and health/safety issues. Brass etches in comparison are easy, do the artwork and send it off. First one is expensive, the rest are not. Not good for curvy bits though.
One of the reasons solder is getting more difficult to find (the low melt types) is that manufacturing facilities are becoming fewer.
Nigel
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http://www.finescale.org.uk/index.php?route=product/category&path=446_453
http://www.finescale.org.uk/index.php?route=product/category&path=446_452
Cheers MIKE
I'm like my avatar - a local ruin!
I'm like my avatar - a local ruin!
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Nigel
©Nigel C. Phillips
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No fiddly soldering iron here.
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White Metal Casting | Toy Soldier Miniatures | Themed Chess Sets
adaptable to model railways i think.
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http://www.tiranti.co.uk/EdgeImpactShop/subcatdivision.php?Division=241&Content=Hand+Casting+Starter+Kit+
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