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,
I would try Aero Solder and flux from
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.
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 http://www.jwharris.com/ to get in their Frames setup,
then look at the chart at http://www.jwharris.com/jwref/chart /
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...
--<< Bruce >>--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
You think that's scary? How about MIG welding aluminum to steel?
"California is the breakfast state: fruits, nuts and flakes."
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.