Brass solder questions

[JeeperCreeper]

What's the best way to get the old solder off of brass? I have a PGP where the top tube was mostly broken off, so I finished breaking the solder and now i just have the mess to clean up. I was thinking heat, but I dont want to separate the bottom 2 tubes. Can I make a water bath to keep the bottom joint cold while I torch the old solder off? I tried my soldering iron but it's old and too weak.

Would the water bath also work to keep that joint together while soldering a new tube on top.

What is the best solder so use on brass?

[prologix]

soldering iron and solder wicking tape

[XEMON]

The best way is to heat it up and brussh it off with a wire brush ... But it won't be perfect ... Solder create a surface alloy so the color will never be perfect without sanding it afterwards.
If you manage your heat properly you can do it without de-soldering the rest of the gun ...

Soldering iron won't get hot enough to melt silver solder.

If you'd rather stay cold, sand/file it off till it's where you want it.

[JeeperCreeper]

I plan on a few mods, then a full polish

[WALZ]

I would try taking a medium fine file and file the soloder off using the file vertically only..
If you file vertically only you will not leave file ines in the brass tube. Then using 220 grit wrapped around a small block of wood finish sand the residue off. You can go 320 and 400 to finish off.. try not to sand every witch way and only use vertical strokes...
Now take some mother's wheel polish and using small,dabs start rubbing it out... Should come out shiny goodness...

[WALZ]

If you are going to resolder a new top tube to the body just file and lightly sand the old solder.
For your application I would just use some tie wire to secure the tree tubes together firmly..
No gaps...
Use mapp gas instead of the stand propane, it burns much hotter and will get the job done without heating the marker up to much..
Use a good zinc based flux and heat the tubes to be soldered with a couple of light passes
(Try not to get the flame into the joint line as this will burn the flux and make a shitty looking joint..)...
and then concentrate on the lower tube mostly, it's thicker and will need a touch more then the top tube.. Touch your solder to the joint to be soldered as your heating lower tube and when solder starts melting into joint move down the line making sure to keep heat on it until lyou complete solder joint..
Let cool off and your done.....
you can then use some 400 grit to finish off and repaint, powdercoat or polish as you see fit...

[JeeperCreeper]

Thank you for some knowledge WALZ
I have a small amount of experience soldering copper pipes and with welding, so this shouldn't be too hard for me.

I have these. Its silver solder, but I'm pretty sure this flux isnt for brass. I'll have to take a trip to the hardware store.

I did manage to get the solder off and sanded it out up to 800 grit for now.

[XEMON]

i would recommend acid flux, much better than the paste. But its acid, it splatter and smoke and its acid ... everythgin nearby will rust and the smoke is toxic ... But dam it makes the solder flow nicely!!!
I can take a picture of the bottle (amd the solder too) i have if you want.

[jeramiej]

Great info in this thread. Thank you for posting it.