Joined: Jul 2015
Posts: 7,498
Likes: 3,301
From: NW Oregon
Bikes: 1982 Trek 930R Custom, '91 Diamondback Ascent w/ XT, XTR updates, Fuji Team Pro CF road flyer, Specialized Sirrus Gravel Convert, '09 Comencal Meta 5.5 XC, '02 Marin MBX500, '84 Gitane Criterium bike
hmmm... 22.2mm... a schwinn seat post?
gotta be stronger than one of these i guess.... they're aluminum...
Ebaty Search: "Adapter 1" Threaded Fork to 1 1/8" Ahead Stem 22.2mm 150mm Alloy"
the quality of the welding you mention, and any ANNEALING required to reduce embrittlement, is what will matter the most.