I do not complain Raphael.......interesting I am a member of the
 Red and the 
Blue French model boating WEB sites........I am sure you are also a member in both sites.....you know....KBIO, Claude, Rookie...........and another WEB site where two slightly scale plank in frame models of Seakadet 
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Also on the Paddleducks WEB, a member site name  = Hankwilliams [Thomas Hilderbrand from Germany], manufactures his own boilers and Custom Gas Tanks
One gas tank he has produced is silver soldered from 90 degree copper elbows and a few straight tubular sections to to form a large 
U shape.......web link below is a great read
http://www.paddleducks.co.uk/smf/index.php?topic=7191.msg41698#msg41698__________________________________
I type in English, and the WEB does the translation to French for other members....I set the machine to the auto translate French to English option
I know this is text only, but I do not see any subtitles embedded in your Videos
Derek