Broken easy out

I've got a customer that had the sprocket on his Road King work loose while he was on a trip. It sheared off 3 of the bolts that hold the sprocket to the rear wheel. He took it to a Harley shop wherever it broke. They drilled 1/4" holes through the 3/8 bolts and drove a spiral easy out into the first bolt. The easy out broke off It's a cast aluminum wheel that has been chromed. We were able to get to the back side of it and tried driving it out with a pin punch, heated the area with a torch, and were not successful. Is there a drill bit that would be hard enough to drill through the easy out? Is there another approach we could use get results?

Hi Curt, been a while since I've posted here. When I worked in a mold shop as a tool maker we never had much success drilling out broken taps or easy outs, some we would use a carbide endmill to remove them but most would be sent over to the EDM department to be burned out.

Thanks Neil: That was my first thought, but finding someone around here with an EDM machine is almost impossible. I guess we could ship it somewhere.

Don't know why anyone still uses Easy Outs they always break flush. I would smear anti splatter everywhere except the Easy Out and weld a nut to it. As soon as it cools enough that it isn't red anymore Back it out. I grind a slight taper on an allen wrench and drive it in like an Easy Out works just as well and if I get crazy and break it it breaks at the bend leaving room to grab it with Vice Grips and remove it.
Dusty

[Pa]

Take it to a machine shop where they have a tap burner. They can burn it out without even marring the hole. We used them to burn out broken bottomed out taps, broken drill bits and broken easy outs. The tapped threads in tapped holes were not even damaged by the tap burner when we burned broken taps out.

Thanks, pa. Looks like any type of EDM machine is gonna be hard to find. Maybe Denver or K.C will be closest. I called the biggest machine shop in western Kansas and asked. "Hey do you guys have an EDM burner?" The guy says 'What the heck is that?" So I said "If you gotta ask, you probably don't have one." I explained to him what it was and he's heard of them, but had never seen one in operation... Probably never heard of YouTube, either....... They are a good machine shop, though, not to take away from their abilities. It obvious I'm gonna have to ship it off to get the job done.

Curt, did you ask them if they could use a carbide endmill and mill them out?

[Pa]

Curt. The one we used was portable. we could mount it just about anywhere. Try a larger industrial type machine builder.

Just take out the broken bolt, the easy out will come out with it

I have had pretty good luck with a air engraving tool. soak the stud with Aero Kroil first. the vibration from the engraver help loosen crud. it a step up from sitting there banging on a center punch to get the broken bolt to start backing out.

Also if you can heat that broken easy out up cherry red you can drill through it with a good bit while it is still glowing. a left handed Cobalt is what I would try if you can go this route. We use to do this to drill a hole in drill chuck keys so you could put a chain through them and wrap em up around the chuck when you forget to take them out.