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John Bump
Works at Texas Instruments
Attended Reed College
Lived in denver
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John Bump

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Spitfire/Datsun carb throttle actuator.  Original in steel, my repro in aluminum.  Weird rounded peg is where the throttle cable attached (mine will wind aorund the circumference.)  The arc is the choke kick-down, the hole near the center is the accelerator pump, the other hole is the return spring that pulls the throttle to the closed position.  I moved it down into the plane of the actuator A: to make fab easier and B: so the tension is radial rather than off to one side.  Very rough finish: the bit was about worn out.
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+John Bump Oh cool. Something like Megasquirt? ITBs or single throttle body with a plenum chamber?
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John Bump

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Buffalo liver on kamut with steamed broccoli.  Not going to try this again, but it was... edible? which is much better than I felt about liver last time I tried it.  (Which was a looooong time ago.)
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As liquor goes, I didn't think Brennivin was bad, and I'm pretty critical of anything harder than cider, generally.  If you liquefied rye bread, you'd end up with something similar, I think. 
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John Bump

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I love this, as a general-purpose robotic system.
Magnetically Actuated Micro-Robots for Advanced Manipulation Applications They're fast, fairly precise, and have a lot of potential for parallel behavior.  Imagine a parallel pick-and-place machine, or active earthquake compensation.  Or even just building carbon fiber trusses, as in the video.
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Add a little intelligence , perhaps it could be rigged to dismantle.......
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John Bump

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Lunchtime ride.  Friend forgot his cycling shoes, says "I'll just ride in my running sneakers."  I'm all "on eggbeaters?  No??!" and grab a wrench, swipe flats off an insufficiently guarded commuter bike nearby.  Completely nylon black MTB pedals on a Dura-Ace crank.  Classy.  If we'd ridden through Boulder, perhaps we could've started a new hipster trend.  ("Where can I get handmade plastic pedals?")
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+John Wardlaw
I saw these on eBay already, so they either got funding, or they made them anyway.
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John Bump

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I didn't know I wanted to race motorcycles until now.
 
MotoGP 2014 Austin GP, TX (USA) slowmotion
Saturday Practice 
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Yeah, about an hour ago I was doing 56 mph down a mountain road wearing a t-shirt and lycra shorts...
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John Bump

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So I've seen this before, and always reply with the relevant XKCD (#356) but I'd never actually considered the solution before.  I think I can express it as the sum of the cauchy sequence (n-1)!/n for n=3,5,7...infinity.  Thoughts?  (My reasoning: the path between the two points will always be an odd number, the number of paths increases as a factorial, and the resistance will be the number of paths, divided by the sum of the resistor values along a path.)
 
On an infinite grid of ideal one ohm resistors, what is the equivalent resistance across the two marked points?
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You're gonna make me miss my bus.
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John Bump

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Carb bracket in aluminum, also with big gouge from when bit loosens in collet from too much vibration.  Oh well, this is why flycutters were invented: to erase mistakes.
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Among the several benefits of a cnc mill, +Mark Rushing, are that it's low speed, the bit is held between the spindle and the workpiece, and it's a little tiny bit.  Regardless, I was wearing eye protection and often have a piece of lexan between me and it.
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John Bump

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After a 100K today, I'm sort of wishing I'd chosen this bike instead.
 
Comfort Commuter with Pegs - LUCKY!
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Oh yes, that would make sense!
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John Bump

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Minor Spitfire update: machining carb bracket.  Original steel one, bent and mysterious, serving to attach throttle return spring, and both throttle and manual choke cable attachments.  Replacement test piece in plywood.  The final piece will be in aluminum with a vertical stiffener that will also act as the cable housing stop (with barrel adjusters.)
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+David Bump -- that would be a very depressing number, and complicated insofar as the hours spent originally improving it vs. the hours spent fixing it after the timing chain floated vs. the hours spent making improvements that I would not have had the timing chain not floated are hard to separate.
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A friend gave me a broken Garmin 500: mounting tabs snapped off.  Rather than buy another back (a, because I'm kind of skint and b, because they'd likely just break off again) I inset a little piece of brass in place of the plastic tabs.  Very fussy work.  The worst was taking these screws and shortening them by 3 threads, using a jeweler's saw, under a microscope.  The guy that sold them to me said "I'm sure glad I don't have to work with stuff like that."
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It's on my list of how-to-remove-this-from-that.  Like, if you break off a steel tap in aluminum, you just simmer the piece overnight in very dilute sulfuric acid (or a sparex solution) and the next day the aluminum's fine and the tap is completely gone.  Same with if you break off brass in aluminum: enough ammonia over time and it'll be gone without damaging the AL.
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electron wrangler
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  • Texas Instruments
    present
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Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
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denver - loveland colorado - leadville colorado - portland oregon - seattle washington - boise idaho - fort collins colorado - eugene oregon
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Mad scientist
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John, aka Random, aka smellsofbikes, aka several other things.
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Mad scientist. Not crabby, just at an oblique angle to reality.
Education
  • Reed College
    chemistry, 1986 - 1988
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Married
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Random, smellsofbikes, jens, solipsist
They had what I needed, found and brought it out fairly promptly, and helped me load it. They have a great assortment of wood and hardware besides.
Public - 8 months ago
reviewed 8 months ago
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