Welders for SMALL Items

I am considering doing some modeling where I will need to make welds on the various models.
The welders that I usually use will be much too big.
Could someone discuss what is available for SMALL welds and the issues that need to be considered?
I am currently looking for an used welder similar to these welders.
http://www.aaproducts.com/ABIWelders.html
Has anyone built a welder for small delicate welds? If so, I would like to hear about it.
Thanks
TMT
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Too_Many_Tools wrote:

Most expensive: Laser welders. Neutec makes one with a built-in binocular microscope. So expensive that my catalog does not list the price. You can also lease them.
Arc welders: ABI makes them for tiny welds. $3000-$5000 USD.
Water torches (no kidding -- hydrogen and oxygen is electrolized from the water) $1200 - $2300. Flame comes out of what looks like an injection needle. Good for places that are fire zoned not to allow tanks.
Smith Little Torch kits and other oxy/acet/propane micro torch kits, about $100-$300 plus cost of tanks and regulators (I am able to use normal full size regulators and tanks). Smallest flame of the oxy/acetylene model has .006 inch orifice size.
Jewelers' supply catalogs have a selection.
--
mbstevens
http://www.mbstevens.com/x4x2002/index.html
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"Strictly I.C." has had articles on SMALL spot welders, and "Review of Scientific Instruments" has had several as well.
www.strictlyic.com
www.rsi.aip.org/
Luck, Bob
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The link seems to be.........
http://rsi.aip.org /
Any idea as to what issues?
TMT
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Bob Murray wrote:

I found this link interesting... http://www.ganoksin.com/borisat/nenam/welding-applications.htm
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Wow is that ever an expensive solution. Much cheaper to just buy a small spot welder from Miller with the timer option.
<http://millerwelds.com/products/spotwelders/msw_and_lmsw__air-cooled_/

Full retail price with timer is around $1000.
You can make custom tongs from copper barstock.
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I got one of these little Lincoln Inverter welders: http://tinyurl.com/2qkark
Mine came used off of eBay for $175. Keep an eye out, and you can get a great deal!
"Too_Many_Tools" wrote:

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