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Discussion Starter #1
As I get nearer to actually begin building models, I'm wondering if one of those small micro torches as adverstised in Micro Mark--or an equivalent--are of any worth?

I know how to solder, braze and weld, but my big torch is just that: made for big stuff. (Though I have tiny tips, I don't like the idea of oxy/aceteylene tanks in my basement).

So, to solder brass I've always used silver solder and you need serious heat to do that. I wonder how much silver soldering is actually done on brass engines and the like? It appears that tin/lead solder would do as well, though it's inherently weaker. But my engines will be small, probably not exceeding six drivers, F scale.

I notice Micro Mark offers a very low temperature 'silver solder' that's "Twice as strong as lead solder!" Is that some kind of epoxy, and if so, is IT any good?

Using an iron is an option, but finding a 100+ watt iron with small tips--or tips for same--might be an issue in this day and age. I suppose I could turn some out of hard copper, but that's not appealing.

WHat's 'MAPP gas'? I hear good things of it but have never had a need, since I have both gas and electric welders.

Basically, all I want to do is neatly solder the occasional brass frame or cab together, or perhaps a metal trackside accessory.

Do any of you use micro torches, and if so do you like them?

Thanks, Les
 

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I have a small soldering iron for electronic work, a weller type gun for bigger stuff, and...



For bigger needs. I don't use it very often.
 

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I've heard resistance soldering is the way to go, especially if you are going to be adding a lot of smaller details.
 

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Odd. It's from my web server.

It's a Ronson butane torch. $25 from Wal*Mart. Comes with a hot air tip and a soldering tip, that I haven't used.
 

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Discussion Starter #6
By,

I know little of resistance soldering. Thanks for the hedzup. I'll look into it. I don't so much intend to do small details, supposing glue/epoxy should suffice, but I am curious about the frames, shells and heavier parts that tend to get stressed by handling, running and whatnot.

Les
 

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Discussion Starter #7
Torby,

The second time I went back and pulled your post up it was there. Thanks for sending the pic along. Price looks pretty reasonable too. Flame seems 'fat' compared to MicroMark's Mini torch--but where there's mini-flame there's also likely mini-heat, which could be bad, too.

Les
 

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I have one of the Micromark torches, and I use it frequently.


Micromark MICRO-TORCH Item Number: 82559


If you do any work on large pices of brass or copper, then a conventional soldering iron won't work - all its heat gets dissipated into the conductive metal. I used to to re-solder all the bars on the pilot of my Accucraft C-16, for example.
Silver solder works at a higher temperature, so a conventional iron won't work. We use it on live steam engines where the burner might melt ordinary solder. My C-16 has a new number on the smokebox door that I had to silver-solder, as it is right in front of the burner. I use Micromark STAY BRITE SILVER SOLDER AND FLUX, 1/2 OZ. EACH(+) Item Number: 80822
 

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Les

Larry Mosher (MLS User ID: lvmosher) used the micro-Mark torch to build his all brass Gilpin tram cars. I went back in the archives to link to the old topic but found that all of the pictures have since been moved or removed so the links only show the little red x's. Anyway, based on what I've seen accomplished with this torch and documented here on MLS, I'd say that it should fulfill your needs.
 

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Discussion Starter #10
Pete,

Many thanks for the reply and the addr. If you do live steam, I'd expect you know what you're talking about.

Maybe I won't need one--though I'm always looking for an excuse to buy a new tool--since I don't do steam.

The one project I do forsee needing a good weld (or braze if I can get away with it) is, I'm going to start chopping up gearboxes that I've collected to try to regear an engine or two, and shafting will be needed. I also want to animate some of the trackside buildings, and the ability to heat and bend on a small scale might be just the ticket.

Thanks again for the info.

Les
 

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Discussion Starter #11
Steve,

As I posted Pete, I'm not real sure what my needs will be. I'm a tool nut, but I also foresee a need for high temperatures in a small space coming up when I get to start my RR.

Thanks for the input.

Les
 

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Discussion Starter #13
Harvey,

I rarely use my big torch anymore. There's another good reason to buy that little thing.


Les
 
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Les,
When did silver smithing that torch does heat the heck out of the joints. I would say you WILL like it after you played with it and worked with it.
And is good for a tool junkie too!
Toad
 
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Les,
One thing that never got answered. Mapp Gas and here it is by Wiki


MAPP gas is liquefied petroleum gas (LPG) mixed with methylacetylene-propadiene. MAPP is the tradename for a product of the Dow Chemical Company. In Australia it is known as RazorGas and is a trademark of ELGAS.


The gas is used in combination with oxygen for heating, soldering, and brazing due to its high combustion temperature of 2927 °C (5300 °F) in oxygen. Although acetylene has a higher combustion temperature (3160 °C, 5720 °F), MAPP has the advantage that it requires neither dilution nor special container fillers during transport, allowing a greater volume of fuel gas to be transported at the same given weight. MAPP was advantageously used in underwater cutting, which requires high gas pressures (under such pressures acetylene polymerizes explosively, making it dangerous to use). However underwater oxy/fuel gas cutting of any kind has been replaced by exothermic cutting due to the much faster cut rate and greater safety.


MAPP like all of the Liquified Petroleum gasses is not appropriate for welding of steel, due to the high concentration of hydrogen in the flame. The hydrogen infuses into the molten steel and renders the welds brittle.


The gas is also used for brazing and soldering, under combustion in ambient air, where it has considerable advantage over competing propane fuel due to its higher combustion temperature. A typical MAPP gas brazing operation would involve metals such as aluminum, copper, et al braze (sometimes colloquially and inaccurately called silver solder) steel parts together.


Plumbers use both MAPP gas and propane for pipe soldering and brazing, but MAPP gas's higher combustion temperature makes such jobs quicker. MAPP gas is also popular among glass lampworkers, for instance glass bead makers.


The biggest disadvantage of MAPP gas is cost; it is between two and four times as expensive as propane (depending on quantity, supplier, and bottle size). While nine kilogram propane cylinders are common, the largest MAPP cylinder available in Australia is three kilograms. Additionally, MAPP gas torches often cost more than propane torches, around 3 times as much.


MAPP is colorless in both liquid and gas form. The gas has a pronounced garlic or fishy odor at concentrations above 100 ppm, due to the addition of Mercaptans for safety, and is toxic if inhaled at high concentrations.
MAPP gas is being replaced in industry by other LP gas mixes, because one of the constituent gasses, Propadiene, is becoming more valuable to the plastics industry than the welding industry. Flamal and Chemtane are two of the newer LP gas mixes on the market.

Toad
 

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I have a couple of the Master Appliance MT11 torches. Run on cigarette lighter butane refills. Really good for smaller work, heat-shrink tubing and LIGHTING MY CIGARS!!
 

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Discussion Starter #17
Toadster,

Thanks for the extensive info on MAPP gas & the micro torch.

It's all but certain I'll buy one as soon as finances loosen a tad. Just got Grandma's new wall furnace installed. She's 89, will be 90 in Feb. Her mind's clearer than mine.
Have to put in a ceiling fan, a window a/c, do some drywalling and trimwork, and ONE project is out of the way.

Now, where can one buy a torch like that and avoid Micro-Robber's prices?

Oh, FWIW: don't buy their ratcheting tap wrench. You need to be able to back your tap up every quarter-turn or so, depending on the metal you're tapping, to clear the threads, esp with the tiny taps.

Les
 
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Our friends at Harbor Freight have a small torch that is much better than I expected - I have seen them on sale for significantly less than $10.00 and the ones that I have work very well.

They have a piezo starter and a base that keeps them stable on a table top. They take standard butane fuel.

I have used them for all manner of soldering projects. Keep an eye out for a sale!

Link to: Harbor Freight Torch




dave
 
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Dave,
Those are nice unless your like me I have destroyed several (more than I want to count) but that is me. I am ruff on my stuff.
I can not even have those plastic tool boxes!
Toad

Sad ain't it!
 
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