Brass model soldering questions

I have not been very successful with irons or guns on brass models.    I have been most successful with brass repairs with electric resistance soldering.    This concentrates the heat at the joint.    I have learned that both surfaces need to be clean before the attempt.

Your plan to clean well and tin sounds very good.    I am not real experienced with this so my lack of success with irons  is probably not a good qualifier.   

You do need to be careful not overheat the surrouinding surfaces and distort the brass panels.    so the hard part is getting enough heat to melt/join the solder without getting so much as to damage the parts.   And both parts have to get hot enough to melt the solder.

Why do I feel setup.  On the other thread you asked about soldering a specific model.  That model is made of fairly heavy brass.  Far heavier than most anything else you're going to come across except maybe an old brass cast door stop.  I provided you an answer for the specific model.  To use the information provided to speak to general repairs is apples and oranges.

What to use for general brass modeling is a loaded question.  I use large & small torches, a good resistance soldering machine, a digital hot air machine, soldering irons, and guns.  No one tool is correct for every task.  I like Stay-Brite solder and flux but I also use plain 60/40 and No-Korode flux.  Shoot, I still use solder paint sometimes.  Sometime I braze, sometimes I soft solder.

Why do I feel I'm wasting my time here?

Jay

You are not.  That is excellent advice, and on point with the question.

Which reminds me - time to search Amazon for "Nokorode."

Bob,

Petroleum based.  Cleanup with solvent, not water like acid based flux.  You may find it's a lot like the old Oatey you were talking about.

Jay

First suggestion is that you might want to practice with some scrap pieces. The more you do, the more "feel" you gain. Solder will flow toward the heat source. For example, if you are soldering copper pipe, put the flame on one side of the pipe and the solder opposite. The solder will melt and flow around the pipe toward the torch.

Obviously not the same as soldering brass, but an excellent illustration how solder flows toward the heat.

Simon

prrjim posted:

I have not been very successful with irons or guns on brass models.    I have been most successful with brass repairs with electric resistance soldering.    This concentrates the heat at the joint.    ....

^^^ the best advice... the biggest problem you will have is keeping heat away from other parts.  this is the hallmark of resistance soldering.

I used a 300 watt Weller, a propane torch, and a pencil flame butane torch for a long time.  Then I got a 1800 watt resistance unit.  Wow, some serious advantages to using that in many cases.  And some disadvantages as well when you smoke something and half of it disappears. Silver solder and a torch for things you will solder other stuff to later. Resistance, a torch, or soldering iron with regular solder and paste flux for most other things. Resistance or soldering iron and Tix flux and Tix solder for fine detail works for me.  Soldering is really an art that you learn over time.  Resistance soldering without destroying stuff is too.

Anyone who has been doing this or any craft for that matter uses tools he is comfortable with. For one person I know these are the only tools he uses. I think he took affront when I suggested using resistance soldering.

With these tools he produces these and dozens more.

There are solders that melt at various temperatures. Generally, work your way down in temperature as you go, with lower melting points for finer details and do them last. It's an art, and as they say, there is more than one way to skin a cat.

Simon

All great advice. Practice, practice, practice !

Jay C posted:

Why do I feel setup.  On the other thread you asked about soldering a specific model.  That model is made of fairly heavy brass.  Far heavier than most anything else you're going to come across except maybe an old brass cast door stop.  I provided you an answer for the specific model.  To use the information provided to speak to general repairs is apples and oranges.

What to use for general brass modeling is a loaded question.  I use large & small torches, a good resistance soldering machine, a digital hot air machine, soldering irons, and guns.  No one tool is correct for every task.  I like Stay-Brite solder and flux but I also use plain 60/40 and No-Korode flux.  Shoot, I still use solder paint sometimes.  Sometime I braze, sometimes I soft solder.

Why do I feel I'm wasting my time here?

Jay

Your not wasting your time in my view, some of us like or need to here stuff either a few times or  like a 2x4 in the head 

PBL has a great DVD on various techniques of soldering in model railroad applications, including resistance, iron and the torch.  It's converted from video tape so it's standard definition.  - on the bright side, you don't need a 4K TV monitor to watch <g>.

...gregg