i gotta ask as i don't know too much about the different soldering techniques
are your joints silver soldered or normal electrical type soldering
still very awesome
MIK
Plumbing NOT flux cored, all sorts of long term problems with that, I use a separate flux. I have given the parts a good test and for the pens foreseen use its OK. Working on the silver solder though. Not expecting these pens to be used that often. The first I sold 6 months ago is still going strong. Sold to a friend and used him as a test bed since. I've asked him to keep me informed about any issues to rectify in future pens. Not heard a single thing from him about it apart from the reaction it gets when he produces it to use. It was a copy of the first one I showed with all the pipes on it. I still have the original and it too is still going strong.
The key is to get the metal really clean and a nice fit of the parts and then make sure you pickle it afterwards to remove the flux as long term it's corrosive.
As regards Silver Solder, the problem is the melting point. It requires a blow torch to reach the required temps. When you have multiple small parts to attach in such close proximity the torch doesn't give the heat localised enough so they just keep falling off every time you heat it. It can be done as when the solder melts, it dissolves some of the surrounding metal so it alters it's melting point. It takes some skill which at the minute I'm still building. There are several melting points you can get so you can start with the highest and work down but it's still a bit hit and miss. The differences aren't huge and a torch builds temperature so quickly on such small/thin parts it's still a bit tricky.
I want to be silver soldering with the high temp (less silver content) as it's better match colour wise to the brass. Silver solder is basically brass with silver added to lower it's melting point. Higher content of silver, lower the melting point. I am trying to build in sub sections to accommodate it and then use the lowest melting point to hold them together. The initial cost is high though, silver solder ain't cheap.