I know how I do it, but what about you guys?

Here's the current situation:
A Porsche tech was working on a track car. When he tried to bleed the brakes the bleeder broke.
He then stuffed a tiny bolt extractor in the bleeder and promptly broke it off.
The next step was using a Dremel with a carbide burr to generally make a mess out of things.

They brought me the caliper for repair.

This one is fairly delicate. I'm working with an aluminum caliper, steel bleeder, and a hard 1/10" diameter extractor.
The caliper has a tall shoulder next to the bleeder so you can't spin more than about 180 degrees unless the tool is 2" long. To complicate things, you can't drill straight through. The bleeder has a machined seat. Screw that up and you're looking for a new caliper.
A replacement caliper is available but it would have to come from Germany.

The client came in today. The tech brought him to see me. He asked when I would be done with the job because he wants to go racing early tomorrow morning.

My plan of attack is to clamp it to my mill and stuff a carbide bit through the extractor.
When I have it cleaned up, I'll heat the caliper then invert a can of Dust Off to chill the bleeder from the inside. The extractor should come out.


Since most people don't have vertical mills at home, how would you guys fix this?

Dynamite.............. or tried drilling in reverse. then off to a machine shop to see if they could help

I've heated broken extractors cherry red with the hot wrench then hit it with a blast of cutting oxygen & it will fly back out but I'd be afraid to use that technique on an alum piece for fear of damaging the surrounding casting?

I'd order a new caliper and RENT the customer a nice race car, with a nice markup!
Aluminum caliper, steel bleeder and a machined seat. What are you supposed to do, use anti-sieze?
I also wonder how often the techs there use extractors? I have had very poor luck with them; they seem to shatter more often than not, especially the small ones.

This is an aluminum brake caliper. You do NOT want to get it that hot.
It only needs to be hot enough to expand a wee bit.
Aluminum transfers heat easily. I will have to take my time to get it hot without burning the finish or damaging the seals.
Race car or not, it's a Porsche and the owner is concerned with appearance.

Easy job, really Feets. Just wrap the adjacent area with some scrap insulation soaked in water. Hit the easy out with a torch blast, or if it is a delicate small piece, a 000 tip and once it is glowing, crank up the oxy knob. Aluminum transfers heat very fast, and you won't hurt the caliper. If you were local, I'd have that out for you in a couple minutes. I'm thinking you are going to ruin it with the mill; let us know how that idea worked out.
-dulcich

A sharp punch and hammer, busts the easy out into pieces.

The extractor came out easily enough.

The bleeder was in for good.

It was a tiny extractor stuffed into a tiny hole inside a fat 10 mm bleeder. The extractor was bottomed in the bleeder and wedged in very tight.
I opened the hole one drill size and tried a heavier straight flute extractor. No dice.
Penetrant was no help.

I tried heating the bleeder.
I tried freezing the bleeder with aerosol.
I tried freezing the bleeder from it's center hole while the caliper was hot.

Each time something failed, I'd clean it up and take the next step.

Since it wasn't the brake caliper for my car I had no sense of urgency and took my time.

Nothing was working.
Eventually, I drilled it out and tried running a sharp 10 mm x 1.0 tap through it. No dice. The steel bleeder remains are STUCK to that aluminum. The steel was pushing the tap into the aluminum caliper. I stopped before it damaged the second row of threads.
The drill left enough meat for 75% depth on the threads according to my charts. I could see aluminum and steel spirals.
With a great deal of work I was able to use a sharp steel pick to get about 10% of the threads clear. Strangely enough, I was only able to pick out the steel in the center of the threads, not the top or bottom. The steel simply won't let go of the aluminum. I've never had that happen before. Usually, when you get to that point the old screw threads twirl out or break into pieces. Not this time.

It didn't appear to be cross threaded. What I can see of the threads does not look heavily distorted.
When I got the conical bottom part of the bleeder out of the hole the bleeder was clean but the bottom of the hole had some scarring around the perimeter.
It would take a pretty harsh environment for steel and cast aluminum to have a galvanic reaction but that's all I can assume.
The caliper is off a Porsche 964 race car. That means it's 18 to 23 years old. That's a LOT of heat cycles.

I did a quick Google search but did not find over size bleeders for a Porsche.

In a pinch, I could drill and tap the caliper one size larger and use a bolt and copper washer to plug the hole.
You could still loosen the bolt to bleed the outside pistons but it opens up a whole world of liability.

The car owner is a lawyer who just paid a bill today for hot rod work that exceeded what I paid for my daily driver. I'm sure he knows all about liability. When we spoke today he expressed a desire to get some track time in the morning but understood the situation.

At this point, the caliper is not damaged. If someone smarter than me could get the steel out it would still be a good caliper. I had my spindle stop set so the cutters would not damage the bottom of the bleed port.

I've already called the tech and told him the situation. He has a good rapport with the client and will pass the info along.

The caliper is like the red one on the left side of this pic.

Copious cursing