johnmar78

Folks, I need a serious advice here please.

I tried to solder brass to copper, and it does not stick. 2mm plate to 1 mm plate-tiger turret.

But just on brass alone np, it sticks well. I use 50/50 solder with built in rosin which is 50%tin 50% lead.
I use 60w electirc solder iron.

I cleaned the copper surface either flux or sand paper, and it just sticks a little and pull it off easy.

My questions is 1),,should i use HCL acid to clean copper or zncls flux(did not work)

2) should I use lead free solder that got 96% tin?//

3) any thoughts please?

Tanque

For starters don't use rosin core solder. Use solid wire or rod solder. It is better to use an acid
cleaner /flux and try to heat the parts indirectly. I'd try to borrow a heavier soldering iron; I use
a 100w, 300w and 500w soldering iron ( "American Beauty" brand) depending on the parts to be joined.
If the parts are large enough or thick I use a propane torch. Always heat indirectly as much as possible.
Too high heat applied directly to fluxed areas can cause poor solder wetting problems in my experience.

BTW in case there's any doubt when I use the term soldering iron I mean soldering iron. I've even used
irons heated in a heating station ( flame).

One has to recognize that sometimes you run across a situation that for whatever reason just defies your
best attempt at soldering... :-(

Just a few suggestions

rrudytoo

My Feedback: (27)

Silver solder is used exclusively for structural bonding and it has great strength. Resin core solder, as a rule, is intended for electrical applications and has little strength. One cannot interchange one for the other and get acceptable results. You can usually get silver solder from Home Depot, Lowe's or Ace Hardware. Good luck!

Al

johnmar78

thanks folks, i try silver soldering and hotter iron.

Tanque

True silver solder requires much more heat! It is more of a brazing function than soldering. Silver solder will
require johnmare78 to bring his parts up to a possibly unacceptable temperature leaving them too soft. Silver solder / braze takes more practice and a completelydifferent flux. I do mostly silver solder for my parts so I know that process fairly well.

Soft soldered parts are quite strong snd the parts so joined usually retain most of their original hardness.

You didn't tell us what you are making but I would stick ( no pun intended ) with soft solder for now.

Jerry

skosti

There are a few basics to soldering. Follow these rules and it should work every time.

First CLEAN CLEAN CLEAN Everything Both surfaces you want to solder scour or sand them then wipe with an alcohol soaked rag
Clean the tip of your iron, heat it to full temp then dip it in flux then wipe with a clean cotton rag, or wipe it on a damp natural sponge you can get these for the purpose at radio shack or any place that sell soldering stuff. If the tip is not almost mirror like you might need to sand or file the tip Be aware though that tips are usually plated and filing will remove the plating this mostly happens with older well worn tips nest the solder use solid solder with a separately applied flux wipe the solder with a rag dipped in alcohol

second the iron It MUST be powerful enough for the job from the sound of it you need at least 150 to 200 watts with a good sized pyramid tip if the iron is to small the work will drain all the heat from it before reaching soldering temp.

Flux, never use acid flux, use rosin you can also use lemon juice ( the real thing not that stuff in the plastic lemons) in both cases clean the flux off after the joint has cooled. use alcohol for rosin or plain water for the lemon juice.

johnmar78

thanks guys, tried this morning agin, brass is ok but failed again on copper with 20cm by 10cm piece, but works fine with 2cm by 2 cm small piece. it seems that my soldering iron is uner p-owered for big piece. So I will get a small butane pen to heat up the copper befroe solder.

johnmar78

tanque, i am making tiger tank metal after seeing dukes tank.

rrudytoo

My Feedback: (27)

johnmar78,

Something to consider is the use of JB Weld instead of soldering. Granted, it takes a while to harden but you won't get the pieces apart once the adhesive sets and it will bond most any metal to anything else. Another advantage to using JB Weld is that it can be machined, filed, sanded and, in some cases, molded. Just a thought.

Al

PS: I've used Stay Brite Silver Solder along with the included flux for years in my RC airplane hobby to bond copper, brass and steel without a problem. I have utilized a Weller soldering gun rated at 100 watts that has served me well over the years. My dos centavos.

johnmar78

thanks Ruddy, sorry for my ignorance, what is JB weld????[&o] Do you have any links or examples? Please

city hunter

Might as well jump in here. I had a issue trying to solder some wires onto some small motors last night.. I gotta go look and see what solder I was using but it works for most wire to wire, and other omtors I've worked on. I believe its a 50 50 rosin lead possibly.

The stuff just would not stick to these tiny motor tabs.

johnmar78

if alumium, no

HondoBob

JB Weld is a high strength epoxy sold in various retail stores in the US, especially automotive parts stores. I ownfour Jeeps and keepJB Weld in every toolbox; I'veused it on anything that doesn'tget hotter than 800F. I'm sure you can easily find a comparible high strength 2-part epoxy down under.