How to deal with a tiny stripped screw on a gadget

boing
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Concerning easy-outs:

If you have exactly the right size easy-out and the metal of the easy-out is significantly stronger than the screw (i.e. it’s not a crappy Horrible Freight one being used on a hardened bolt) and you carefully drive it a little ways into the target hole, but not so much that it bites through to the threads, they work great. Lotta caveats here, including a requirement for what Pirsig called “mechanic’s feel.”

If you bust off an easy-out, you will discover that the metal of the easy-out is nearly impossible to drill; I can do it with a drill press but I only know one person who can do it by hand (and he can torch out bolts, too, so we’re dealing with extremes of hand-eye co-ordination not reachable by the common man). The drill bit will want to skitter off the shear surface of the hardened easy-out and bite into the surrounding metal or possibly your hand. If you press too hard the bit will bend and skitter anyway, or else snap off and embed itself into your safety glasses.

If you have a situation like @anon27554371 where the bolt’s already got a stripped allen hole, knocking on the right size easy-out until you get a good bite and then turning with a small crescent wrench will usually work. You’ll need a quality easy-out, though, and if you bang on it too hard you’re likely to find out that your threads are brass or pot-metal, and as @wrecksdart says the hole has to be deep enough that the easy-out does not strike bottom. :frowning: I usually try to find a slightly larger allen (a metric one for an SAE allen, or vice versa) and knock that in with a small hammer before I resort to an easy-out. And I’d never use an easy-out on anything that I could get a vise-grip on.

Pirsig talks about all this on P250 of Zen and the Art of Motorcyle Maintenance, I think.

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Feel free to attempt tapping/threading the end of an Easy Out, but if you do, please video your process and know that Easy Outs are generally made from hardened steel that has a slight tendency to resist being drilled.

See also what @Medievalist wrote above.

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When it comes to rounded-out allen bolts and screws, the first thing I try is a torx bit (the kind with a 1/4" hex drive). They tend to have a slight taper on their splines, which really helps bite into the corners when you gently hammer the bit in. Generally works a treat above 3mm.

For smaller stuff, like the bastard 2mm grub screws that hold the brake pivot pin in STI levers, I came up with an alternative: get some foil (start with more than enough) and tightly wrap it around the key, and twist off the excess where it overlaps the end. This part gives you the ability to jam as much foil as will fit in, but you shouldn’t be able to at first; after the first attempt, remove a little foil and try again. Once you have the key in place, surrounded by the maximum amount of foil that will fit, it’s surprisingly effective. Of course, don’t forget the penetrant lube.

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He also explains that a broken bolt is why you become a mechanic. If the removal and replacement of a motorcycle part was able to be written down step by step, ( or nowadays on a YouTube video), and never went wrong we would soon hate our jobs.

I try to remember that every time something breaks, or goes wrong.

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