Weld retip a claw on an emerald 

This video shows how I reduce the risk of retipping a claw on an emerald with the emerald still in the ring.
I use the Lampert PUK 5 jewellery welder to weld the tip on.
I start by cutting the existing remnants of the claw away from the emerald to expose the edge of the emerald so that I can lay the new claw onto the surface of the emerald and weld it solidly onto what is left of the existing claw (welding the tipping wire on sideways protects the emerald from the blast of the weld, which could harm it)
Then I build it up to be strong by welding it while holding gold wire close to the weld so that the wire gets sucked into the weld.
I snip the tipping wire off, being careful not to snip the emerald.
At the end of the video is a photo of the finished job after cleaning the soot off and shaping and polishing the claws (not shown in the video - I may do a video to show this process).
The settings used on the PUK 5 are :
Gold, welding mode on the left of the five modes (standard mode on the PUK 3) 25 to 30%
The ring is 18ct yellow and white gold.

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