Brazing aluminum

Greetings all -

How do you braze or solder a brass fitting to an aluminum manifold? Thanks, Willer

Reply to
Willer
Loading thread data ...

A tin-zinc solder or pure tin would probably work with the right flux, some better than others of course. Tin silver solder (as Harris Staybrite) might work with the right flux. Harris Staykleen is not the right flux here, don't know what might be.

Some will say that lead-tin solder works if the al is scrubbed while soldering. I've never had what I considered satisfactory results from this, YMMV.

I would try Aero Solder and flux from

formatting link
It works very well for al-to-al and/or al-to-copper, so I'd expect it to join al to brass as well but I've never tried it. If you're not in a hurry, I'll try it with brass when I return later next week and let you know how it works.

Reply to
Don Foreman

KISS. ;-) You put down the torch, and drill and tap the aluminum manifold to NPT threads. (Or metric if you're on the other side of the pond.) Then you thread the brass fitting, coat with the appropriate thread sealant for the material in the manifold (Teflon tape or good ol' Rectorseal #5) and screw them together.

Joining dissimilar metals like that can be done - J.W. Harris says to make it a two-step joint, with a piece of steel tubing or pipe in the middle. First braze the steel to aluminum with 'AlBraze-1070' filler and flux, then the copper/brass to the steel using one of the 'Safety-Silv' series fillers and 'Stay-Silv' flux.

First go to

formatting link
to get in their Frames setup, then look at the chart at
formatting link
I would be concerned about the differing rates of expansion making it crack in service. And if the filler metals get mixed when you put it together, all sorts of odd things can happen...

-->--

Reply to
Bruce L. Bergman

You can't, because the thermal coefficients of expansition for these two materials are so totally diffent.

Harry C.

Reply to
hhc314

See

formatting link
Hold my beer....

Reply to
Don Foreman

Not to mention the electrolytic corrosion that will immediately start at the jumction. Bugs

Reply to
Bugs

You think that's scary? How about MIG welding aluminum to steel?

formatting link
Tim

-- "California is the breakfast state: fruits, nuts and flakes." Website:

formatting link

Reply to
Tim Williams

I'll try brazing first.

Reply to
Don Foreman

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.