Thank you all for helping me out!!
The caul is screwed to the vice and I steam the piece with the metal strap 1,5 m away from it.
But I will try this:
A hook at the metal strap.
Preparing a new caul with a bigger radius - about 4-4,5" for the molle ash bow.
Doing more trials with the 3", with the vice and freehand. - hopefully I can keep some!
Soaking the tips for a day
I already glued on some laminations to the maple, maybe I will use the trial errors for brush nocks.
Thank you for the help, if there is more let me know.
First I will buy a electrical cooking plate, running out of butane again. I guess boiling with electricity is cheaper. Than preparing trial pieces - I'll let you know how it goes...
B2W