this week

i've been under the weather for most of three days. maybe it's the water out here or something.
we're building a single speed 29er for Mountain Goat cycles. Chris welded up the front end yesterday. OX Gold DT was a pain to miter in the mill because the 38 mm cutter was a little dull, so Chris did it by hand with aircraft shears and the belt sander. it was a little gappy so he did 2 passes with the TIG, the first to lay in some steel to close up the gaps, the second to make a nice clean bead. it came out prettier than i've seen TIG look.
he had me do the chainstay-dropout brazes (sorta testing my skills) and they came out looking OK. it was tough because the dropouts are stainless Paragon sliders, and all we had on hand for filler was low-fuming bronze. i remember Omar Khiel wrote that brass brazing stainless is possible, but i'd never seen it done. actually i assumed the dropouts were plain steel when i was brazing them, and wondered why the brass didn't want to flow the way i was expecting. Chris said the secrets to brass brazing stainless are higher heat and super-cleanliness. i think the brazing was complicated a little further by using old was Gasflux brand, usually blue-green, but this was the bottom of the bucket and it had turned brown.
that was last night around midnight, and i took most of today off. when i got back into the shop this evening, Chris had unbrazed those single-bend chainstays and brazed in some s-bends and the rest of the rear end. apparently the single-bends didn't permit enough tire clearance.

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