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Mechanics and Construction => Mechanics and Construction => Topic started by: _Moonbot_ on February 22, 2011, 07:17:24 PM

Title: Brazing?
Post by: _Moonbot_ on February 22, 2011, 07:17:24 PM
Is brazing as strong as welding?  I mean, if I were to hit a brazed joint with a hammer a couple of times, would the joint hold, or brake?
 ???
Title: Re: Brazing?
Post by: garrettg84 on February 22, 2011, 08:25:16 PM
Depending on what you are brazing, the joint can actually be STRONGER than welding.
Title: Re: Brazing?
Post by: Aberg098 on February 23, 2011, 09:41:21 AM
Yes, brazing can be stronger than welding in certain cases. Typically, it is used to join dissimilar metals, that you couldn't fuse together using welding. Other times it is used to minimise the heat affected zone that you would get from a welded joint.

I am guessing you are asking this question from the point of view of a hobbyist. Brazing using hobby equipment is difficult but it can be accomplished. To keep things simple, you may want to consider other joining methods like glue, bolts or rivets.

Edited for logic!
Title: Re: Brazing?
Post by: Soeren on February 23, 2011, 10:22:24 AM
Hi,

Is brazing as strong as welding?
It depends... On methods, filler material used, fluss used, how well the materials to join are cleaned, how the heat is applied and how much heat is applied.

Back in the old days, fine bicycles were brazed together to be strong.


I mean, if I were to hit a brazed joint with a hammer a couple of times, would the joint hold, or brake?
In Denmark, brazing is called "slag-lodning" which means something like "hammer/beating/stroke" soldering because the method is more akin to soldering than welding, but it can take a hit with a hammer.

A well performed soldering with the right methods and the right filler material (there is a plethora of different alloys in the market today) is almost as strong though, but the term was coined long before all the really strong alloys were "invented".

I'm quite fond of brazing myself, mostly silver "brazing" on brass, but for eg. aluminum, soldering is easier (if you have the right fluss).

As mentioned by another poster, do consider the your almost infinite options and materials for joining two materials. In bonding (gluing/chemical welding/etc.) it's even more important to clean the materials (a lack or proper cleaning is the cause of most bonding failures). Bolts and pop rivets are quite forgiving and the latter can be had with an inner thread that you can "pop" on an then use a screw, if you have to be able to disassemble later.


BTW: Joint's don't brake (meaning to stop eg. a car), if anything they break  :P
Title: Re: Brazing?
Post by: _Moonbot_ on February 23, 2011, 04:37:03 PM
Depending on what you are brazing, the joint can actually be STRONGER than welding.


I think aluminum.  A Battlebots style robot is what I'm trying to make and I need to make an angle.
Title: Re: Brazing?
Post by: _Moonbot_ on February 23, 2011, 04:38:21 PM
Yes, brazing can be stronger than welding in certain cases. Typically, it is used to join dissimilar metals, that you couldn't fuse together using welding. Other times it is used to minimise the heat affected zone that you would get from a welded joint.

I am guessing you are asking this question from the point of view of a hobbyist. Brazing using hobby equipment is difficult but it can be accomplished. To keep things simple, you may want to consider other joining methods like glue, bolts or rivets.

Edited for logic!



Can you bolt an angle? (without a ton of mechanical stuff, just a drill)
Title: Re: Brazing?
Post by: Aberg098 on February 23, 2011, 04:58:13 PM
Sure you can bolt an angle, but this is very specific to the size, shape and thickness of the surfaces you want to join. Is it possible for you to provide us with a drawing or diagram of what it is you are trying to make?
Title: Re: Brazing?
Post by: _Moonbot_ on February 23, 2011, 06:19:19 PM
Sure you can bolt an angle, but this is very specific to the size, shape and thickness of the surfaces you want to join. Is it possible for you to provide us with a drawing or diagram of what it is you are trying to make?

It's a right or 40 degree angel.  I don't have any drawings yet
Title: Re: Brazing?
Post by: Aberg098 on February 24, 2011, 09:34:06 AM
Is the material you are using fairly thick?

If not, try making or finding something like this :
http://img.en.china.cn/0/0,0,284,684,360,360,6f4b4eaa.jpg (http://img.en.china.cn/0/0,0,284,684,360,360,6f4b4eaa.jpg)
Angle brackets are available in a variety of angles. You can then use a drill to make holes in your material for bolts or rivets. It's also possible to glue these in place. Again, this depends on your application and specific details. A drawing or picture would help us help you.
Title: Re: Brazing?
Post by: _Moonbot_ on February 24, 2011, 04:33:27 PM
Is the material you are using fairly thick?

If not, try making or finding something like this :
http://img.en.china.cn/0/0,0,284,684,360,360,6f4b4eaa.jpg (http://img.en.china.cn/0/0,0,284,684,360,360,6f4b4eaa.jpg)
Angle brackets are available in a variety of angles. You can then use a drill to make holes in your material for bolts or rivets. It's also possible to glue these in place. Again, this depends on your application and specific details. A drawing or picture would help us help you.

I'll draw one up.  An angle bracket is a good idea.  I was also thinking of angle iron  ;D
Title: Re: Brazing?
Post by: _Moonbot_ on February 25, 2011, 03:54:38 PM
Sorry, my computer won't let my upload any pictures of my problem.  :'(
Title: Re: Brazing?
Post by: BANE on March 02, 2011, 12:32:28 PM
if you're looking into aluminum; this method looks pretty good and cheap.  Personally, i've never used this, but i want to now after seeing this vid
aluminum brazing soldering using alumiweld welding rods (http://www.youtube.com/watch?v=CJ42scaWFnw#ws)
Title: Re: Brazing?
Post by: garrettg84 on March 02, 2011, 02:02:20 PM
HTS-2000 Aluminium Repair For The New Millenium (http://www.youtube.com/watch?v=N-cv3R4fWZc#)

HTS-2000 for aluminum to aluminum brazing. I have some of their rods and all seems to be just as described in the above video
Title: Re: Brazing?
Post by: photomark on March 04, 2011, 02:41:31 AM
Brazing or gas welding of Aluminum is very difficult and will take a lot of practice to perfect, the best way to weld Aluminum is with the TIG process , the only problem there is that all these cheap inverter TIG welders are NOT suitable for welding Aluminum as they only give a DC output and you need AC for TIG welding of Aluminum.

It also take around twice the power to weld .

Any standard MIG welder can weld Aluminum but you need to change the liner in the gun lead to a teflon type and use just Argon gas and of course use a roll of Aluminum wire.

As with any welding of any type it takes practice to perfect any Aluminum is one of the more tricky materials to weld

Not all Aluminum is weldable 

Thee is a solder for Aluminum but I have never used it  , I think it is called Alusol