I have the Clarke version of the op's flare tool from machine mart.
https://www.machinemart.co.uk/p/cht172-automotive-pipe-flaring-kit/
I have used it on vehicle to make bubble flares on steel pipe. I got the technique from this video.
I made a depth gauge to get the correct protrusion (about 6mm i got some steel pipe from the scrapies to practice on)
The real secret to success was to use red rubber grease on the die
https://www.amazon.co.uk/RUBBER-GREASE-LUBRICANT-CALIPERS-PISTON/dp/B00BBUMWNQ/ref=pd_sim_sbs_auto_6
this grease is compatible with brake fluid
https://www.machinemart.co.uk/p/cht172-automotive-pipe-flaring-kit/
I have used it on vehicle to make bubble flares on steel pipe. I got the technique from this video.
I made a depth gauge to get the correct protrusion (about 6mm i got some steel pipe from the scrapies to practice on)
The real secret to success was to use red rubber grease on the die
https://www.amazon.co.uk/RUBBER-GREASE-LUBRICANT-CALIPERS-PISTON/dp/B00BBUMWNQ/ref=pd_sim_sbs_auto_6
this grease is compatible with brake fluid