Aluminum Brazing Rods

[sanddrag]

Has anyone used Aluminum Brazing rods before? I picked up some cheap Bernz-O-Matic ones at my LHS just to play with. Since it has working temp of 700 degrees F, I was able to melt it with my propane torch. I tried putting together a small piece of 1/8" thick L channel onto some .090 plate and it seemed to work reasonably well. I was able to pull it apart with a couple pairs of pliers and not a whole lot of effort, but it did hold relatively well. I mean, when it was brazed all around, both the plate and the angle bent before I could get it apart.

Anyway, what has been the extent of your success with these. They seem to make the metal "stick" together more than they do "bond" together because you aren't melting the base metal at all.

What I'm getting at is, can an aluminum FRC robot frame be brazed together and hold reliably? Would you need to use a higher temperature rod and torch?

I don't have any experience with brazing, so if anyone else has, please share.

[Rod]

Originally Posted by sanddrag

Has anyone used Aluminum Brazing rods before? I picked up some cheap Bernz-O-Matic ones at my LHS just to play with. Since it has working temp of 700 degrees F, I was able to melt it with my propane torch. I tried putting together a small piece of 1/8" thick L channel onto some .090 plate and it seemed to work reasonably well. I was able to pull it apart with a couple pairs of pliers and not a whole lot of effort, but it did hold relatively well. I mean, when it was brazed all around, both the plate and the angle bent before I could get it apart.

Anyway, what has been the extent of your success with these. They seem to make the metal "stick" together more than they do "bond" together because you aren't melting the base metal at all.

What I'm getting at is, can an aluminum FRC robot frame be brazed together and hold reliably? Would you need to use a higher temperature rod and torch?

I don't have any experience with brazing, so if anyone else has, please share.

Yes you can braze Alum together. I have always used silver solder and brazing flux. The higher percent of silver in the rod the better. The more contact surface you have the stronger it will be as the silver solder will "Flow" where a weld will not. It is an easy way to join Alum., but is no replacement for a TIG torch. But if you have enough contact surface it will hold very well, sometimes better than a weld.

[piotr_boch]

What you want material join ( number alloys aluminium)?
If you want good join you must to heat aluminium to temperature about 577-580degrees C=1070-1086deg.F .
When I join pipe to pipe I use special wire AA4047 or AA4045 or nocolok flux( wet mixture to assist flame brazing).
If you have question please write.