I didn’t find the standard thirdhand to be helpful in holding things to be soldered. They slipped and moved at the slightest touch. Soldering became a chore. There had to be a better way. One of my favorite things to do is to modify tools to fit my needs.
My first thing was to find a way to make the locking tweezers stay where I placed them. That is why I drilled a hole through the tweezers and the pivot to insert a bolt with a thumb lever. This makes the connection solid and the lever makes adjustments easier. I keep all the parts movable but also tight so they stay in the position I put them. I only grasp the thumb lever or the thumb screw. I never grasp the tweezers to position a piece since they are holding the jewelry to be soldered and the piece will drop off of them.
I have been using this set-up for the past five years. I have soldered many different configurations with this pair. I am still finding new ways to hold things. Spend the time setting up and then you don’t have to touch or move anything to complete your soldering. I put my set-up on a soldering board that is on a turntable. That way I get to turn the piece to see all angles before I solder.
When I am soldering a ring shank to another component I put the piece on my soldering board by itself. I insert the ring shank into the groove of the thirdhand. I move the thirdhand set-up to get close. Then I grab the shank on both sides with my thumbs and fingers and pull the shank in the position I want it to be. I have found if I try to move the base of the set-up it is a little tricky. By grabbing the shank with my fingers I have more control to make it straight and in the position I need. Once it is set the base will not move.
Tip: If you file a flat place on your shank where it comes in contact your piece it will be more secure, and easier to keep in place, and provide a stronger solder joint.