Junior Member
Solder not flowing!
Argh, please help as I am going slightly mad with frustration!
I am using silver soldeer strip and borax, heating the whole piece, ensuring it is clean, moving around to build the heat, the borax puffs, then the solder forms in to a ball and will then stay that way!
I also tried with solder paste and it is just hardening but not flowing!
PLEASE HELP!
Super Moderator
That sounds as though you need more heat in the piece. What are you trying to solder, and what torch are you using?
Junior Member
its a silver bangle and I am using a blow torch like this http://www.toolstation.com/shop/Hand.../sd3158/p43245
I have made this item before and it worked fine, just wont work today?!
Super Moderator
OK, that looks gutsy enough - and the fact that you've done it before underscores that. So... What are you doing differently? It isn't down to solder cleanliness if the paste is doing the same - so I'm still inclined to think it's the amount of heat you're putting in. When you've done this previously, have you had a firebrick or anything behind the bangle to reflect the heat?Originally Posted by sparkleprints
Junior Member
No, but it was a little while ago, so I am starting at the opposite end of the bangle, gradually heating side to side around to the area to be soldered, but as soon as I go near the solder it is heating into the ball and then thats it, no amount of heat anywhere on the bangle is making a difference.
So would you say I need to heat the rest of the bangle more? Its 3mm thick, how long would you say?
Super Moderator
My usual approach is to heat opposite the joint first to create a reservoir of heat; remember that silver is a fantastic conductor, so if the rest of the piece isn't hot, all the heat you are putting into the area around the joint is being drawn away, meaning you'd need to pour even more heat into the joint to get it to temperature... The rate of heat transfer is proportional to the difference between the 2 areas, so the hotter you have the "cold" part, the less quickly the heat is drawn away from the hotter part.
The last wide bangle I did needed the opposite side at around annealing temperature to allow me to solder the join cleanly; this is where firestain preventatives like Argotect (or Magic Boric now that I finally have some to try) really help - the longer you hold a piece at heat, the more likely it is to suffer from firestain.
Senior Member
Dear S_P
Your torch should be OK, but what usually happens with bangles that are long and thin is that the heat is rapidly lost again as you move your torch away. Then, the solder balls up from being heated before the bangle joint is hot enough.
One answer, as Peter has said is to build up a cave of fire bricks to retain and spread the heat. Another, which I use on bigger pieces is to tote two torches, so that I can apply the heat more evenly.
If you have not done so, you might also look at this http://www.cooksongold.com/forum/hot...html#post39487 . Anyhow, please let us know how you get on. Dennis.
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