Does solder stick to zinc coated metal?

Clean bare metal always adheres the best.

Also use an active flux like one used for plumbing, not those used for electronic work. Zinc solders relatively easily.

Pete

It would be probably easier to get a brass nut. Brass solders easy without any corrosive flux!

Thanks for all advice.

Mannyrock

But you will still need the proper flux to solder the brass nut to the steel plate (at least in my experience).

I know that this post is a couple weeks old.  I did a job something like this Manny, and I adhered the nut to the plate with JB-Weld.  It's still holding, so I'll certifiy that JB-Weld is one way to do it.  Good luck!

I use plumbing flux for a job like this, then just clean it up thoroughly with water before use.  You'll need plenty of heat for that steel plate, so I'd consider the Propane torch for this job.

Thanks for all of the suggestions.

If I had to do it all over again, I would probably use the JB Weld stick roll.  I ended up using the plumbers' solder and flux, and it work out, but it was more difficult than I thought it would be.   Probably because I used my soldering iron instead of a propane torch. I had to do it a little at a time, in layers, almost like TIG welding.      I didn't try the torch because in my limited experience with copper pipe fittings, once the torch heated up the metal, the solder melted immediately upon contact with the metal, and would run everywhere, almost like water.   I am sure that a more experienced guy could have managed well with the torch though.

Mannyrock

The problem with doing the solder in layers is it has no strength, so don't be surprised if it breaks free.  Truthfully, using JB-Weld on a flat and relatively smooth surface isn't going to have much strength either, so that's really not a good replacement for soldering, brazing, or the like.

Why not file off the zinc coating?

Charlie

There's no real reason to remove the zinc coating, it'll solder just fine if you have the proper heat.

70/30 tin/zinc solder works easy AND proper heat. it should take well to zinc AND steel

....... if you have the proper heat.

Key.  This is why having a little pencil torch in addition to a soldering iron in your shop is good.

@Mannyrock posted:

Thanks for all of the suggestions.

If I had to do it all over again, I would probably use the JB Weld stick roll.  I ended up using the plumbers' solder and flux, and it work out, but it was more difficult than I thought it would be.   Probably because I used my soldering iron instead of a propane torch. I had to do it a little at a time, in layers, almost like TIG welding.      I didn't try the torch because in my limited experience with copper pipe fittings, once the torch heated up the metal, the solder melted immediately upon contact with the metal, and would run everywhere, almost like water.   I am sure that a more experienced guy could have managed well with the torch though.

Mannyrock

Plumbers solder has higher melting point and the newer lead free is even worse. 60-40 or 63-37 is much better, just use the proper flux for bare metal. A 45 watt pencil iron is OK for a screw head but anything larger you either need a bigger iron, small torch, or a resistance soldering tool.

lots of youtube videos on building brass trains or similar will show you the various techniques.

Pete

Yep, this sure got complicated.

If I do this again, I think I'll go to a welding shop and ask them to just hit it a few times with a MIG welder.

If they know what they are doing, it'll take all of 5 minutes.  :-)

Mannyrock

@Mannyrock posted:

If they know what they are doing, it'll take all of 5 minutes.  :-)

Or less.  I guess getting ready is 4 1/2 minutes.