Does anyone know a shop in the city that can repair partially stripped pedal threads on a crank arm versus replacing the entire crank? I'm looking for something like this:
Something on the north side would make things easier but I realize beggars can't be choosers. Any mechanics out there feel free to plug how awesome your shop is. Thanks for any input!
I don't know of any shop that specializes in pedal threads, but I'd guess that anyone with a 9/16 x 20 (or if you have a one piece crank 1/2 x 20) tap can ease out smallish damage on your crank and get your pedals to fit. You might be able to fill in the little gaps with blue Loctite if it's a little bit wobbly. I bet most bike shops can do it or so can you with a tap and some oil. You're sure the pedal itself isn't stripped? If so, new pedal vs buy a die to rethread that too.
I think more elaborate repairs like those you might try on an engine block aren't worth it and wouldn't solve things well (filling hole, retapping threads...). Alternatively, and maybe better, if it's the LH (non drive side) crank just get another one of any brand that's the same length (165, 170, 175 mm...), making sure the square hole is oriented like the old one (square vs diamond - different brands) - it'll work fine. If it's the drive side you might have to replace the crankset or at least the spider. Try used places for more unmatched (high end or low quality) cranks than you can shake a stick at. Or you can take the pedals off and use it as a balance bike.
Unless you have something really special to salvage it's just not worth it.
Like it was said above just replace it. Go down to Working bikes and dig through what they have. I'm sure they will have something for you for $5-8 that is either the exact same crank arm you have or something even nicer.
If they are only moderately damaged any shop can fix them.
If they are badly damaged they can have a threaded insert installed but it is not cheap. Bring it to Rapid Transit north when I work and I can take a look at it for you.