MICHAEL KEARSEY

Dorrigo, Australia

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Hi JD, I had this welding table laser cut. I TIG welded it mostly from the inside but wanted to fill the top tab cavities with something, so they didn't collect garbage.

Welding the cavities would no doubt have worked well. I didn't need that level of strength and didn't want' to introduce any more heat than necessary.

The answer was SilBro again, and it was easier to grind down with a flap disk.

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JD Brewer
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Hi JD, The yoke of this cast vice had broken one wing completely. It holds the threaded block in place.

I originally started padding up with 309 stainless filler. While it certainly wetted to the cast iron, it began peeling up the cast material on the second pad layer or so. It seemed the 309 expansion was way to strong for the cast.

I then reverted to SilBro which I should have started with. I padded up almost to the same height as the original wing. Ground it back with the die grinder. I would have been grinding for hours with the 309. I was difficult to get inside the vice cavity for both welding and grinding. 309 was bad choice to for several reasons.

The Silbro worked well. While I don't really load this vice up, I would be quite confident to do so.

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JD Brewer
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Hi JD, Some time ago, I cut some rust from the bottom of this land rover door. The aluminium door skins tend to rust out the steel frames. This is a good one after 40 years!!!

This door was submerged in molasses for a couple of weeks.  I chose to only go so far with this. I can seal it up with various product just fine.

The remaining door skin varied substantially in it's thickness due to rust. Some paper thin parts I still managed to braze OK. It's a gentle process compared to welding.

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JD Brewer
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Thanks JD. SilBro is a goto for me with lots of things. Last weekend I repaired this trolley cross member which had broken away from the tube. By the time I'd cleaned it up, the gap at some points was large. The tube wall thin. Inside the tube was rusted and inaccessable.

I knew that if TIG welded, the impurities from the back side would enter the weld pool.

I knew the chance of blowing through the tube was high with other processes.

I SilBro-ed this with quite a large fillet. You can see in later images, the other side wont hang on for long.

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..... It seems to me that at a very micro/macro level you can't avoid nipping into that base when you start a TIG braze. However, once you have a small silicone bronze pool taking that arc instead of the base material, the bronze pool can heat the base material, not weld it. The bronze pool is then acting like a heat diffusion layer between the arc and the base metal.

That's just how I look at it. I'd be interested in other opinions.

Great video, great outcome with the sander.

Great video JD. A really good outcome with squaring up the tube ends too.

This video is very representative of the repair jobs I seem to do. When you have a father who collects old, broken machinery which I somehow seem to inherit, I suppose that's the reason.

The TIG brazing process is very interesting. From my research and observations, when you strike an arc on the base metal, the electrons will pick out a single spot on the +ve surface through which to flow. The plasma (argon stripped of it's electrons and forming ions) is set up around that arc, lowering electrical resistance compared with everything else around. The arc keeps going to that spot. The spot in turn becomes very hot and begins melting. Great for welding but not so great for heating. It's heating that we need for brazing.

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24 Nov 20:20

Wow, looks perfect!!! Was there anything particular wrong with it?