kahn41

My Feedback: (4)

Why cant i get silver solder to stick to music wire and brass? Sticks to brass fine but just runs off the music wire. The solder i'm using is lead free silver bearing solder, is there a special flux?

dbacque

My Feedback: (3)

I use the Stay-Brite Silver Solder kit and yes, it comes with a bottle of acid flux. The other key is the correct heat. Too hot and the solder will just bead up and run off. Not hot enough and it'll melt but not stick and if you do get it to stick, it won't run into the joint correctly. I used to use a torch but it would take lots of tries to get it to stick. Turns out I was getting it too hot. But a small soldering iron wouldn't work well either, not enough heat. Now I've got a 45W Weller soldering iron and it's just the ticket.

Dave

kenh3497

I would think there is flux for the material you are using. I guess the silver solder I'm used to is one step below bronze/brass (used for brazing). That does take a special flux. With all that said, are you getting the wire hot enough? The brass, if it's sheet will heat up a lot quicker that the wire. I'm pretty sure you need to use a propane torch and maybe use it with MAPP gas to get enough heat.

OK, I just wnet on a hunt and found this;

http://www.google.com/#sclient=psy-a...638b897581bb57

Section 3 says melting point of 440F to 480F and uses rosin flux. Sounds like a heat issue (not enough) to me. Regular propane will be enough. Don'
t have to use MAPP.

kahn41

My Feedback: (4)

I am using a propane torch the heat is hot enough to get the 1/8 inch wire red. I know that is to hot but trying to get the solder to stick to a plain piece of wire... just rolls off, ill try some different flux tomorrow

kenh3497

I'm sure you are already doing this but sand the wire to make sure there is nothing on the wire. The sanding also gives the solder a bit of mechanical bite to the wire.

dbacque

My Feedback: (3)

If you're turning the wire red it's way too hot, like I said before if it's that hot the solder will bead up and roll off. If you're using a torch turn the flame down low, back off and heat the work a little slower. That way you'll find the temp where the solder will stick and flow.

Seriously, I have given up using a torch to solder music wire since I got the 45 watt soldering iron. What was always a struggle is now as easy as pie.

Dave

pkoury

My Feedback: (7)

If the wire is red hot you are changing the temper of the wire. Is the solder being melted by the metal or by the torch? If the metal is the right temp it will melt the solder and allow it to flow into the joint. Sounds to me like you are getting the metal to hot.

TFF

There are different lead free bearing solders; most are for soldering water pipes and are confusing in name to get away from the old lead poisonous kind. Most of what you see at a hardware box stores. Stay brite or Stay Brite8 are what we want. These are low temp solders and if you use a torch you are just boiling the solder off. The high content silver solder 25% silver and up are the ones for torches; they are strong but are big money with the price of silver.

jester_s1

I've soldered steel wire several times with a torch and even with propane and the flame turned way down it is really easy to overheat the wire. My way is to touch the tip of the flame just for a second and take it away to let the heat spread out. One of two more touches is all it takes to get the soldier bubbling (that's how you tell if the heat is right). I touch the solider to it and it will flow if there's flux and it's hot enough. It may take one or two more split second touches with the torch to fill the joint with solder, but usually just a second one will get it done.

JeffinTD

I've found a butane micro torch works well for me. With a little practice you can control temp when joining pieces that dissipate heat differently. I sand things well, then clean with a pump spray bottle with alcohol, followed by liquid flux.

Be sure to clean the joint again once cool when using acid flux.

OldScaleGuy

My Feedback: (2)

The correct flux is a must.
Correct heat is very important.
Clean is important but what you miss the flux will take care of if applied correctly.
Proper tinning of your iron is very important.
I never use a flame for silver bearing solder, only true silver solder then i use MAPP gas which creates higher heat.
Like any thing else, practice!

kahn41

My Feedback: (4)

turning the MW rod red hot i don't do, I gradually heat it up but it still wants to roll off. I can solder copper pipe all day long without a hitch. But two different metals kind of allude me... More practice and different flux

scale only 4 me

My Feedback: (158)

Just like when you sweat copper, you don't want to blast the flux with the open flame of the torch, when you do thing with a plumbing joint the flux in inside the joint and doesn't get hit by the flame directly,, if you hit it with the flame the materials can carbon back up and nothing sticks.

When using a torch I try to heat the wire adjacent to the joint allowing the joint area to slowly heat up until the flux boils away and the solder melts/flows.

I agree with the comment try using a high power soldering iron instead of a torch, it takes longer to heat up but you have much less chance of overheating the joint area and burning off the flux

good luck

triumphman49

My Feedback: (149)

Great advice here for prep'ing and cleaning the joint. Oatey makes a "tinning flux" which I like. It pre-tins the metals, and when the heats getting close, you can see the tinning effect happen.

T-man49
Club Saito 723

kahn41

My Feedback: (4)

thanks for the reply's. I think I have it now, the flame was to high and heating to fast, instead of putting the flux on the wire i put it on the solder instead, worked much better...

ARUP

I only use Stay-Brite and a torch like the ones you get at hardware store. The silver solder wants to flow toward the heat. When music wire is the correct temp to flow the solder via flux you will see a very faint color change in the wire. Red hot is too hot at least in the assembly processes I configure. Here are some pics of parts made with a torch for heat. The first shows bracing rods for a 1/6 Piper PA-12. The music wire has brass tube soldered onto it. The home made 'nuts' are just brass tube on tube with flats filed for looks. The next pics show a brass tube on music wire as a wheel bearing with a cross drilled hole for wheel retention- same airplane. The last pics show the sequence to fabricate a tailwheel. It is functional and the wheel axle is soldered in place. The wheel is plastic and foam from Robart. It takes practice to be able to do this. Anybody can learn to do this but you gotta practice! I use wet tissue to isolate some parts from others in the process. I also use heat sinks in the form of metal clamps to keep from 'disassembling' other portions. I use heat sheilds like aluminum foil to protect items. Do this some place where a fire won't ignite other stuff. I have a fire extinguisher handy but have never had to use it. Knock on wood!

Flypaper 2

There are two different silver solders, soft silver solder, which is the Staybrite stuff. and hard silver that takes a torch to melt. I make mufflers for gas engines with it to give you an idea of the temp it will stand. It takes a powdered flux. For the soft silver solder, I use the trusty old Weller soldering gun for landing gear and such. For more heavy duty heat, I use an 80 watt iron with a 3/8 dia tip to hold the heat. If you get the piano wire red hot, you take the temper out of it and is usless for landing gear. Makes it into coat hangar wire.

Gord.

Desertlakesflying

My Feedback: (28)

Get NoKorode soldering flux (never use the water soluble kind of any brand) from a plumbing supply because Lowes and Home Depot hardly carry it. You can hit this flux directly with the flame. It works the best with silver solder. If you are getting the parts to be soldered to hot then nothing will stick. Try this flux, and you'll see the difference.

I only did service plumbing for 8 years.......I got paid a percentage, not by the hour, so I learned what worked fast.

acerc

I use a soldering gun with the tip cut off. That leaves the two ends that I place on each side of the joint and pull the trigger. Doing it with the tip split puts the joint of the two parts as the contact point for the heat. When the flux starts to bubble it's ready.