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Old 03-17-2018, 09:14 AM   #11
goldstar31
 
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Originally Posted by MRA View Post
Yes, thanks N. - there's some interesting stuff about MIG brazing here (below), along with quite a lot else about welding - but not gas. Still, interesting to link to it here for reference.

http://www.mig-welding.co.uk/brazing.htm
I thought that 'flinging in something different' might stir up a bit of interest.

Actually, this was all 30-40 years ago - upon retirement from bean counting and the need to earn pennies. I did a City and Guilds in Motor Vehicle Restoration at then Gateshead Tech.

Coming from a family who were all involved in engineering- at least from the commencement of steam and probably before that, I was always fascinated but obviously forbidden as engineering was a VERY dangerous and poorly paid pursuit. I was 'shanghai-d' in National Service in that direction. And that WAS bloody dangerous.

So in my dotage, I'm merely playing with what I wanted to do but couldn't then.

Of course, it is far, FAR easier than 'counting beans' though I still do it for charitable purposes.

I've hung one of my dinner suits from last night, got a morning suit out ready for Monday and somehow will try to find a bit of 'displacement therapy ' -in between.

In second childhood--- and mere oblivion

Norman


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Old 03-17-2018, 03:57 PM   #12
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It's amazing, the number of bean counters I know. In fact I am married to one. The way industry has gone here, it's amazing there are any beans to be counted, really - maybe they're counting the counters - kind of 'meta-beans'.


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Old 03-20-2018, 05:09 PM   #13
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On this subject - I've been looking on-line at silver solder too. 55% silver in 1.5mm dia rods seems to be something offered by a local model shop - does this sound like something to have a go with for general purposes?
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Old 03-20-2018, 10:09 PM   #14
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Silver solder is sort of traditional and whilst expensive, is the joining medium between lead soldering and brazing. As you know, a fair amount of heat is required to melt the braze which might be difficult in a small home workshop.

An important point is flux. Once upon a time, borax was generally available but isn't anymore.
I wanted a new supply and went into the chemists and they looked at me as if I had come from Outer Space or Mongolia.. I solved the problem by buying from the local welding stockists and bought the variety that would work well on stainless steel too.

Of course, borax is an excellent killer of ants but I didn't tell you that.

I hope that it helps you-- and not the ants

Norm
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Old 03-21-2018, 04:59 PM   #15
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Borax is available in grocery stores over here as Boraxo - laundry detergent.
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Old 03-21-2018, 06:30 PM   #16
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Borax is available in grocery stores over here as Boraxo - laundry detergent.
I recall your similar reply in--2011. Again, I recall Boraxo being in wash rooms as a
powder in the days when Pontius was a pilate but did you actually braze with the stuff?

Regards


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Old 03-21-2018, 06:53 PM   #17
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I might as well be creative and have washed my formal and evening wear shirts and for a repeat performance, I put a wetted amount of laundry powder on a bit of scrap brass plate and cooked it on the top of my gas oven.

The characteristic clearing of borax never happened but I finally got a charred mess which lit with the characteristic flame of sodium which suggests that there is a clear evidence of --- clears throat- common salt.

Common salt certainly was the cheap
but successful adulteration of detergents. Well, it was -- way back in the 1950's when we were playing about with such things.

N
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Old 03-22-2018, 03:20 PM   #18
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As an aside I bought some borax to use as a scale preventer while heat treating some steel. It protected the steel beautifully. Removal is on par with trying to remove baked on glass. Several hours in a citric acid bath evidently was a spa treatment for the stuff as nothing happened. A Dremel and wire wheel finally got it off.
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Old 03-22-2018, 05:28 PM   #19
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Apologies but I was subject to an attempt to hack me.

So I reply to the removal of glassy borax, everyone in boiler making etc uses a pickle bath. Removing baked on borax CAN be removed with nothing more than a deft finger nail. My dear departed wife simply removed excess borax from children's orthodontic braces was removed that way.

The accepted removal in the workshop was and presumably always will be done by dropping the work HOT into a dilute concentration of sulphuric acid such as battery acid. Clearly, there has to be an element of shock involved.
Failing a supply of H2SO4, I always used acetic acid aka spirit vinegar and the somewhat delightful residue from English pickled eggs and such culinary delights will work.

And I'm NOT joking

N

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Old 04-13-2018, 12:23 AM   #20
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This is so important with respect to any welding process!!! Practice is mandatory and for a home gamer needs to be done regularly even if there is "no need". If waste is a problem come up with welding projects to turn into practice.

Since I'm not a professional and most here aren't the other thing to engage in is welding warm up just before starting on the real project. You want to get the mind and muscles working in sync before attacking a work piece with dozens of hours in it. This would apply no matter the process, be it silver solder, brazing, oxy welding, stick or flux core. Get your machine and mind dialed in before hitting the real stuff.

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Iíve done a little TIG brazing and the best thing I did was just cut some metal up and practice, practhce, practice. It feels like you are wasting gas, rod, metal BUT in the scheme of things and to avoid scrapping a part with many hours work in it I think itís the only sensible path to follow.

I would think the same practice until perfect rule will apply with gas based brazing.

Cheers,
J.


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