I saw your post a couple of days ago, thought someone more experienced than me might reply. Unfortunately these forums are not all that active these days.
Here is what I use for soldering. I use the 40-60 solder from radio shack along with some flux that I bought at the local hardware shop. I don't remember the brand name, but it was a generic one. This solder may not be the strongest one out there, but so far I have built one truck with it, and it is working well. I use the 100W soldering gun sold at radio shack.
I’ve been reading these TTTT sites and what not for a few weeks now thinking i might try it
but
once apone a time i made very small metal stuff such as rings and hinged jewelry and i always used a torch with a very small needle size flame to get the metals to bond to each other but i would also have to use a past style flux and fire scale presenter although fire scale was only to prevent the metal from turning black which depending on your preference you might like that look I know it would look a little more rugged
they where very expensive and since then i no longer have access to the metal shops i use to play around in but the stuff i put together would take a lot of abuse and not brake apart i would toss my idea in and say check out jewelry supplies and how to type pages if you haven’t already just an idea hope it helps its been almost 7 years since I have played around in that area but I figure once I take the time to re assemble all my tools and get a good work area I may just try to build once of these little guys they are very cool and I do like the total custom idea